The invention relates to a universal mapping of resource elements (REs) to enhanced resource element groups (e REG) that applies to both the PDCCH and PDSCH regions; the mapping is universal since it is not user or cell-specific but applies to the resource block pairs irrespective of the actual reference signals used. The mapping is such that all REs of the resource block pair are assigned to one out of a plurality of e REGs. According to the mapping, the REs are sequentially assigned to the e REGs, in predetermined orders. Within an OFDM symbol a pair of REs is assigned to the same e REG, wherein the two REs are spaced apart from each other by 3 or 6 subcarriers.

Long Term Evolution (LTE)
Third-generation mobile systems (3G) based on WCDMA radio-access technology are being deployed on a broad scale all around the world. A first step in enhancing or evolving this technology entails introducing High-Speed Downlink Packet Access (HSDPA) and an enhanced uplink, also referred to as High Speed Uplink Packet Access (HSUPA), giving a radio access technology that is highly competitive.
In order to be prepared for further increasing user demands and to be competitive against new radio access technologies, 3GPP introduced a new mobile communication system which is called Long Term Evolution (LTE). LTE is designed to meet the carrier needs for high speed data and media transport as well as high capacity voice support for the next decade. The ability to provide high bit rates is a key measure for LTE.
The work item (WI) specification on Long-Term Evolution (LTE) called Evolved UMTS Terrestrial Radio Access (UTRA) and UMTS Terrestrial Radio Access Network (UTRAN) is finalized as Release 8 (LTE Rel. 8). The LTE system represents efficient packet-based radio access and radio access networks that provide full IP-based functionalities with low latency and low cost. In LTE, scalable multiple transmission bandwidths are specified such as 1.4, 3.0, 5.0, 10.0, 15.0, and 20.0 MHz, in order to achieve flexible system deployment using a given spectrum. In the downlink, Orthogonal Frequency Division Multiplexing (OFDM) based radio access was adopted because of its inherent immunity to multipath interference (MPI) due to a low symbol rate, the use of a cyclic prefix (CP) and its affinity to different transmission bandwidth arrangements. Single-carrier frequency division multiple access (SC-FDMA) based radio access was adopted in the uplink, since provisioning of wide area coverage was prioritized over improvement in the peak data rate considering the restricted transmit power of the user equipment (UE). Many key packet radio access techniques are employed including multiple-input multiple-output (MIMO) channel transmission techniques and a highly efficient control signaling structure is achieved in LTE Rel. 8/9.
LTE Architecture
The overall architecture is shown in FIG. 1 and a more detailed representation of the E-UTRAN architecture is given in FIG. 2. The E-UTRAN consists of an eNodeB, providing the E-UTRA user plane (PDCP/RLC/MAC/PHY) and control plane (RRC) protocol terminations towards the user equipment (UE). The eNodeB (eNB) hosts the Physical (PHY), Medium Access Control (MAC), Radio Link Control (RLC) and Packet Data Control Protocol (PDCP) layers that include the functionality of user-plane header-compression and encryption. It also offers Radio Resource Control (RRC) functionality corresponding to the control plane. It performs many functions including radio resource management, admission control, scheduling, enforcement of negotiated uplink Quality of Service (QoS), cell information broadcast, ciphering/deciphering of user and control plane data, and compression/decompression of downlink/uplink user plane packet headers. The eNodeBs are interconnected with each other by means of the X2 interface.
The eNodeBs are also connected by means of the S1 interface to the EPC (Evolved Packet Core), more specifically to the MME (Mobility Management Entity) by means of the S1-MME and to the Serving Gateway (SGW) by means of the S1-U. The S1 interface supports a many-to-many relation between MMEs/Serving Gateways and eNodeBs. The SGW routes and forwards user data packets, while also acting as the mobility anchor for the user plane during inter-eNodeB handovers and as the anchor for mobility between LTE and other 3GPP technologies (terminating S4 interface and relaying the traffic between 2G/3G systems and PDN GW). For idle state user equipments, the SGW terminates the downlink data path and triggers paging when downlink data arrives for the user equipment. It manages and stores user equipment contexts, e.g. parameters of the IP bearer service, network internal routing information. It also performs replication of the user traffic in case of lawful interception.
The MME is the key control-node for the LTE access-network. It is responsible for idle mode user equipment tracking and paging procedure including retransmissions. It is involved in the bearer activation/deactivation process and is also responsible for choosing the SGW for a user equipment at the initial attach and at time of intra-LTE handover involving Core Network (CN) node relocation. It is responsible for authenticating the user (by interacting with the HSS). The Non-Access Stratum (NAS) signaling terminates at the MME and it is also responsible for generation and allocation of temporary identities to user equipments. It checks the authorization of the user equipment to camp on the service provider's Public Land Mobile Network (PLMN) and enforces user equipment roaming restrictions. The MME is the termination point in the network for ciphering/integrity protection for NAS signaling and handles the security key management. Lawful interception of signaling is also supported by the MME. The MME also provides the control plane function for mobility between LTE and 2G/3G access networks with the S3 interface terminating at the MME from the SGSN. The MME also terminates the S6a interface towards the home HSS for roaming user equipments.
Component Carrier Structure in LTE (Release 8)
The downlink component carrier of a 3GPP LTE (Release 8) is subdivided in the time-frequency domain in so-called subframes. In 3GPP LTE (Release 8) each subframe is divided into two downlink slots as shown in FIG. 3, wherein the first downlink slot comprises the control channel region (PDCCH region) within the first OFDM symbols. Each subframe consists of a give number of OFDM symbols in the time domain (12 or 14 OFDM symbols in 3GPP LTE (Release 8)), wherein each OFDM symbol spans over the entire bandwidth of the component carrier. The OFDM symbols thus each consists of a number of modulation symbols transmitted on respective NRBDL×NscRB subcarriers as also shown in FIG. 4.
Assuming a multi-carrier communication system, e.g. employing OFDM, as for example used in 3GPP Long Term Evolution (LTE), the smallest unit of resources that can be assigned by the scheduler is one "resource block". A physical resource block (PRB) is defined as NsymbDL consecutive OFDM symbols in the time domain (e.g. 7 OFDM symbols) and NscRB consecutive subcarriers in the frequency domain as exemplified in FIG. 4 (e.g. 12 subcarriers for a component carrier). In 3GPP LTE (Release 8), a physical resource block thus consists of NsymbDL×NscRB resource elements, corresponding to one slot in the time domain and 180 kHz in the frequency domain (for further details on the downlink resource grid, see for example 3GPP TS 36.211, "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation (Release 8)", section 6.2, available at http://www.3gpp.org and incorporated herein by reference).
One subframe consists of two slots, so that there are 14 OFDM symbols in a subframe when a so-called "normal" CP is used, and 12 OFDM symbols in a subframe when a so-called "extended" CP is used. For sake of terminology, in the following the time-frequency resources equivalent to the same NscRB consecutive subcarriers spanning a full subframe is called a "resource block pair", or equivalent "RB pair" or "PRB pair".
The term "component carrier" refers to a combination of several resource blocks in the frequency domain. In future releases of LTE, the term "component carrier" is no longer used; instead, the terminology is changed to "cell", which refers to a combination of downlink and optionally uplink resources. The linking between the carrier frequency of the downlink resources and the carrier frequency of the uplink resources is indicated in the system information transmitted on the downlink resources.
Further Advancements for LTE (LTE-A)
The frequency spectrum for IMT-Advanced was decided at the World Radiocommunication Conference 2007 (WRC-07). Although the overall frequency spectrum for IMT-Advanced was decided, the actual available frequency bandwidth is different according to each region or country. Following the decision on the available frequency spectrum outline, however, standardization of a radio interface started in the 3rd Generation Partnership Project (3GPP). At the 3GPP TSG RAN #39 meeting, the Study Item description on "Further Advancements for E-UTRA (LTE-Advanced)" was approved. The study item covers technology components to be considered for the evolution of E-UTRA, e.g. to fulfill the requirements on IMT-Advanced. Two major technology components are described in the following.
Carrier Aggregation in LTE-A for Support of Wider Bandwidth
The bandwidth that the LTE-Advanced system is able to support is 100 MHz, while an LTE system can only support 20 MHz. Nowadays, the lack of radio spectrum has become a bottleneck of the development of wireless networks, and as a result it is difficult to find a spectrum band which is wide enough for the LTE-Advanced system. Consequently, it is urgent to find a way to gain a wider radio spectrum band, wherein a possible answer is the carrier aggregation functionality.
In carrier aggregation, two or more component carriers (component carriers) are aggregated in order to support wider transmission bandwidths up to 100 MHz. Several cells in the LTE system are aggregated into one wider channel in the LTE-Advanced system which is wide enough for 100 MHz even though these cells in LTE are in different frequency bands.
All component carriers can be configured to be LTE Rel. 8/9 compatible, at least when the aggregated numbers of component carriers in the uplink and the downlink are the same. Not all component carriers aggregated by a user equipment may necessarily be Rel. 8/9 compatible. Existing mechanism (e.g. barring) may be used to avoid Rel-8/9 user equipments to camp on a component carrier.
A user equipment may simultaneously receive or transmit one or multiple component carriers (corresponding to multiple serving cells) depending on its capabilities. A LTE-A Rel. 10 user equipment with reception and/or transmission capabilities for carrier aggregation can simultaneously receive and/or transmit on multiple serving cells, whereas an LTE Rel. 8/9 user equipment can receive and transmit on a single serving cell only, provided that the structure of the component carrier follows the Rel. 8/9 specifications.
Carrier aggregation is supported for both contiguous and non-contiguous component carriers with each component carrier limited to a maximum of 110 Resource Blocks in the frequency domain using the 3GPP LTE (Release 8/9) numerology.
Logical and Transport Channels
The MAC layer provides a data transfer service for the RLC layer through logical channels. Logical channels are either Control Logical Channels which carry control data such as RRC signalling, or Traffic Logical Channels which carry user plane data. Broadcast Control Channel (BCCH), Paging Control channel (PCCH), Common Control Channel (CCCH), Multicast Control Channel (MCCH) and Dedicated Control Channel (DCCH) are Control Logical Channels. Dedicated Traffic channel (DTCH) and Multicast Traffic Channel (MTCH) are Traffic Logical Channels.
Data from the MAC layer is exchanged with the physical layer through Transport Channels. Data is multiplexed into transport channels depending on how it is transmitted over the air. Transport channels are classified as downlink or uplink as follows. Broadcast Channel (BCH), Downlink Shared Channel (DL-SCH), Paging Channel (PCH) and Multicast Channel (MCH) are downlink transport channels, whereas the Uplink Shared Channel (UL-SCH) and the Random Access Channel (RACH) are uplink transport channels.
A multiplexing is then performed between logical channels and transport channels in the downlink and uplink respectively.
Layer 1/Layer 2 (L1/L2) Control Signaling
In order to inform the scheduled users about their allocation status, transport format and other data-related information (e.g. HARQ information, transmit power control (TPC) commands), L1/L2 control signaling is transmitted on the downlink along with the data. L1/L2 control signaling is multiplexed with the downlink data in a subframe, assuming that the user allocation can change from subframe to subframe. It should be noted that user allocation might also be performed on a TTI (Transmission Time Interval) basis, where the TTI length can be a multiple of the sub-frames. The TTI length may be fixed in a service area for all users, may be different for different users, or may even by dynamic for each user. Generally, the L1/2 control signaling needs only be transmitted once per TTI. Without loss of generality, the following assumes that a TTI is equivalent to one subframe.
The L1/L2 control signaling is transmitted on the Physical Downlink Control Channel (PDCCH). A PDCCH carries a message as a Downlink Control Information (DCI), which includes resource assignments and other control information for a mobile terminal or groups of UEs. In general, several PDCCHs can be transmitted in one subframe.
It should be noted that in 3GPP LTE, assignments for uplink data transmissions, also referred to as uplink scheduling grants or uplink resource assignments, are also transmitted on the PDCCH.
With respect to scheduling grants, the information sent on the L1/L2 control signaling may be separated into the following two categories, Shared Control Information (SCI) carrying Cat 1 information and Downlink Control Information (DCI) carrying Cat 2/3 information. For further information regarding the DCI formats and the particular information that is transmitted in the DCI, please refer to the technical standard or to LTE—The UMTS Long Term Evolution—From Theory to Practice, Edited by Stefanie Sesia, Issam Toufik, Matthew Baker, Chapter 9.3, incorporated herein by reference. The different DCI formats that are currently defined for LTE are as follows and described in detail in 3GPP TS 36.212, "Multiplexing and channel coding", section 188.8.131.52 (available at http://www.3gpp.org and incorporated herein by reference).
Physical Downlink Control Channel (PDCCH) and Physical Downlink Shared Channel (PDSCH)
The physical downlink control channel (PDCCH) carries e.g. scheduling grants for allocating resources for downlink or uplink data transmission.
Each PDCCH is transmitted using one or more so called Control Channel Elements (CCEs). Each CCE corresponds to a set of Resource Elements (REs). In 3GPP LTE, at the moment one CCE consists of 9 Resource Element Groups (REGs), where one REG consists of four consecutive REs (consecutive in the frequency domain) excluding potential REs of reference signals. The resource elements occupied by reference symbols are not included within the REGs, which means that the total number of REGs in a given OFDM symbol depends on whether or not reference signals are present.
The PDCCH for the user equipments is transmitted on the first NsymbPDCCH OFDM symbols (usually either 1, 2 or 3 OFDM symbols as indicated by the PCFICH, in exceptional cases either 2, 3, or 4 OFDM symbols as indicated by the PCFICH) within a subframe, extending over the entire system bandwidth; the system bandwidth is typically equivalent to the span of a cell or component carrier. The region occupied by the first NsymbPDCCH OFDM symbols in the time domain and the NRBDL×NscRB subcarriers in the frequency domain is also referred to as PDCCH region or control channel region. The remaining NsymbPDSCH=2·NsymbDL−NsymbPDCCH OFDM symbols in the time domain on the NRBDL×NscRB subcarriers in the frequency domain is referred to as the PDSCH region or shared channel region (see below).
There are two special cases: in subframes containing MBSFN transmissions there may be 0, 1 or 2 symbols for control signaling, while for narrow system bandwidths (less than 10 resource blocks) the number of control symbols is increased, maybe to 2, 3 or 4, to ensure sufficient coverage at the cell border.
For a downlink grant on the physical downlink shared channel (PDSCH), the PDCCH assigns a PDSCH resource for (user) data within the same subframe. The PDCCH control channel region within a subframe consists of a set of CCE where the total number of CCEs in the control region of subframe is distributed throughout time and frequency control resource. Multiple CCEs can be combined to effectively reduce the coding rate of the control channel. CCEs are combined in a predetermined manner using a tree structure to achieve different coding rate.
In 3GPP LTE a PDCCH can aggregate 1, 2, 4 or 8 CCEs. The number of CCEs available for control channel assignment is a function of several factors, including carrier bandwidth, number of transmit antennas, number of OFDM symbols used for control and the CCE size, etc. Multiple PDCCHs can be transmitted in a subframe.
On a transport channel level, the information transmitted via the PDCCH is also referred to as L1/L2 control signaling. L1/L2 control signaling is transmitted in the downlink for each user equipment (UE). The control signaling is commonly multiplexed with the downlink (user) data in a subframe (assuming that the user allocation can change from subframe to subframe).
The physical downlink shared channel (PDSCH) is mapped to the remaining OFDM symbols within one subframe that are not occupied by the PDCCH. The PDSCH resources are allocated to the user equipments in units of resource blocks for each subframe.
FIG. 5 shows the exemplary mapping of PDCCH and PDSCH within a normal subframe (having 2·NsymbDL=14 OFDM symbols in the time domain), respectively a resource block pair (see magnification). In this exemplary case, the first NsymbPDCCH=2 OFDM symbols (PDCCH region) are used for L1/L2 control signaling, i.e. for signaling the PDCCH, and the remaining NsymbPDSCH=12 OFDM symbols (PDSCH region) are used for data. Within the resource block pairs of all subframes, cell-specific reference signals, CRS (Common Reference Signal), are transmitted. These cell-specific reference signals are transmitted on one or several of antenna ports 0 to 3. In this example, the CRS are transmitted from two antenna ports: R0 is from antenna port 0 and R1 is from antenna port 1.
FIG. 6 shows another example where the PDCCH and the PDSCH is mapped to a MBSFN subframe. The example of FIG. 6 is quite similar to FIG. 5, except for the MBSFN subframe not comprising common reference signals in OFDM symbols outside of the control channel region.
FIG. 7 illustrates a resource block pair and the CRS for antenna ports 0 to 3, as defined in the technical standard TS 36.211v10.4 Chapter 6.10, incorporated herewith by reference; in particular Fig. 18.104.22.168-1 where a normal cyclic prefix is assumed.
Release 10 introduces extensive support of UE-specific reference signals for demodulation of up to 8 layers corresponding to up to 8 antenna ports (in LTE Release 10, antenna ports 7-14). Correspondingly, the subframe also contains UE-specific reference signals, such as DMRS (DeModulation Reference Signal) that are used by the user equipments for demodulating the PDSCH. The DMRS are only transmitted within the resource blocks where the PDSCH for a certain user equipment is allocated. In the example of FIG. 8A, only DMRS ports 7-10 are shown since these are assumed to be sufficient for ePDCCH transmissions. It should be noted that at the moment it is not supported to use DMRS for the PDSCH when also using SFBC.
In addition, feedback of Channel-State-Information (CSI) is based on a set of reference signals—CSI reference signals (CSI-RS) which are relatively sparse in frequency but regularly transmitted from all antennas at the base station, while in general the UE-specific reference signals are denser in frequency but only transmitted when data is transmitted on the corresponding layer (see FIG. 8B). The CSI reference signal is transmitted in each physical antenna port or virtualized antenna port and is used for measurement purposes only.
A cell can be configured with one, two, four or eight CSI-RS ports. The exact CSI-RS structure, including the exact set of resource elements used for CSI-RS in a resource block, depends on the number of CSI-RS configured within the cell and may also be different for different cells. More specifically, within a resource-block pair there are 40 possible positions for the reference symbols of CSI-RS and, in a given cell, a subset of corresponding resource elements is used for CSI-RS transmission. In LTE Release 10, the CSI-RS are transmitted (if configured) on one or more of antenna ports 15-22.
FIGS. 8A and 8B illustrate the reference signals DMRS and CSI-RS for a resource block pair, according to one example.
For further information on the LTE physical channel structure in downlink and the PDSCH and PDCCH format, see St. Sesia et al., "LTE—The UMTS Long Term Evolution", Wiley & Sons Ltd., ISBN 978-0-47069716-0, April 2009, sections 6 and 9. Additional information on the use of reference signals and channel estimation in 3GPP LTE can be found in section 8 of this book.
FIGS. 9 and 10 illustrate an exemplary mapping of resource elements to resource element groups within a physical resource block pair. As apparent therefrom, one resource element group comprises four adjacent resource elements within each OFDM symbol. Further, the resource elements that are used for the common reference signals are not used for defining a resource element group; in other words, when assigning the resource elements to resource element groups, the CRS REs are accounted for. Therefore, depending on the position of the CRS in the first OFDM symbol (which is cell specific), the mapping of REs to REGs is different. In particular, when comparing FIGS. 9 and 10, in the first OFDM symbol 0 the REs of subcarriers 0, 1, 3, 4, 6, 7 and 9, 10, the differences are apparent; e.g. resource element of subcarrier 1 and OFDM symbol 0, may be either assigned to REG 1 (FIG. 9) or may be used instead as a CRS (FIG. 10).
Space-Frequency Block Codes (SFBCs)
SFBC is a transmit diversity technique used in LTE. In LTE, transmit diversity is only defined for 2 and 4 transmit antennas and one data stream, referred to in LTE as one codeword since one transport block CRC is used per data stream. To maximize diversity gain the antennas typically need to be uncorrelated, so they need to be well separated relative to the wavelength or have different polarization. The SFBC diversity scheme may be used in LTE for the PBCH and PDCCH, and also for the PDSCH if it is configured in transmit diversity mode for a UE.
More specifically with regard to SFBC, if a physical channel in LTE is configured for transmit diversity operation using two eNodeB antennas, pure SFBC is used. SFBC is a frequency domain version of the well-known Space-Time Block Codes (STBCs), also known as Alamouti code. This family of codes is designed so that the transmitted diversity streams are orthogonal and achieve the optimal SNR with a linear receiver. Such orthogonal codes only exist for the case of two transmit antennas. Multiple subcarriers of OFDM lend themselves well to the application of SFBC.
For SFBC transmission in LTE, the symbols transmitted from the two eNodeB antenna ports on each pair of adjacent subcarriers are defined as follows:
      [                                                      y                              (                0                )                                                                (              1              )                                                                          y                              (                0                )                                                                (              2              )                                                                                y                              (                1                )                                                                (              1              )                                                                          y                              (                1                )                                                                (              2              )                                            ]    =      [                                        x            1                                                x            2                                                            -                          x              2              *                                                            x            1            *                                ]
whereby y(p)(k) denotes the symbols transmitted from antenna port p on the kth subcarrier.
SFBC achieves robustness through frequency diversity by using different subcarriers for the repeated data on each antenna. Basically, an information symbol is transmitted on two different resource elements by using two distinct antennas (spatial component). Provided that the channel coefficient (amplitude/phase) for both versions is the same, the receiver can calculate the original symbol exploiting a diversity gain.
As mentioned above, the two versions of the information symbol are transmitted on adjacent subcarriers to be spaced closely in frequency; in said case, the channel coefficient for both versions can be assumed to be basically the same which improves the accurate regeneration of the information symbol using a simple receiver implementation, as shown by S. M. Alamouti "A Simple Transmitter Diversity Technique for Wireless Communication", IEEE Journal on Selected Areas in Communications, Vol. 16, pp. 1451-1458, October 1998.
FIGS. 11 and 12 are similar to FIGS. 9 and 10 respectively, as far as both illustrate the RE-to-REG mapping for the PDCCH considering the different positioning of the CRS. Furthermore, FIGS. 11 and 12 also illustrate how SFBC may be applied to the PDCCH and to the PDSCH.
For the PDCCH, LTE works such that the SFBC pairs are located as adjacent as possible in the frequency domain within one OFDM symbol; as depicted in FIGS. 11, 12 in OFDM symbol 0 the possible SFBC pairs are each shown in a dashed-line box. SFBC pairs can therefore be mapped to resource elements (k′,l′) and (k′+n,l′) in the same OFDM symbol, where k′ is the subcarrier index, l′ is the OFDM symbol number and nε{1, 2}. In other words, n=1 means that the SFBC pair is located at adjacent resource elements; n=2 means that the SFBC pair is located at resource elements that are spaced apart by two, i.e. one resource element (such as a CRS RE) in between. Therefore, the spacing is equivalent to 1 plus the number of REs between two REs forming an SFBC pair.
Similarly, with regard to the PDSCH, SFBC pairs can be mapped to resource elements (k′,l′) and (k′+n,l′) in the same OFDM symbol, where k′ is the subcarrier index, l′ is the OFDM symbol number and nε{1, 2}. In other words, n=1 means that the SFBC pair needs to be adjacent resource elements; n=2 means that the SFBC pair may be of resource elements that are spaced apart by two, i.e. one resource element (such as a CRS RE) in between. FIG. 11 exemplary discloses SFBC pairs in dashed-line boxes in OFDM symbol 1 and 6 for n=1, and FIG. 12 in the PDCCH region exemplary illustrates SFBC pairs in dashed-line boxes for n=2.
LTE also allows a transmit diversity approach known as a combination of frequency switched transmit diversity (FSTD) with SFBC. FSTD schemes transmit symbols from each antenna on a different set of subcarriers. More information on FSTD is given in Chapter 188.8.131.52 of LTE—The UMTS Long Term Evolution—From Theory to Practice, Edited by Stefanie Sesia, Issam Toufik, Matthew Baker, Chapter 9.3, incorporated herein by reference.
Enhanced-PDCCH
Currently under discussion is to introduce an Enhanced PDCCH (ePDCCH), which is transmitted based on UE-specific reference signals. In order to efficiently use UE-specific reference signals, the mapping of Enhanced-PDCCH is preferred to be allocated in the PDSCH region, as depicted in FIG. 13. In order not to blind-decode the whole bandwidth, it is assumed that the search space of ePDCCH would be limited within a set of PRBs pairs. The set of PRBs pairs can be first configured by higher layer signalling, or at least is assumed to be known by the receiver prior to trying to detect any ePDCCH.
Details for the ePDCCH are currently under discussion and thus not yet decided. Therefore, the following assumptions are made as examples only for illustration and explanatory purposes. In general it may be assumed that a similar approach will be used as for the PDCCH. For example, it may be assumed that the ePDCCH consists of an aggregation of one or more control channel elements; in the following they may be exemplary called Enhanced Control Channel Elements (eCCEs). Furthermore, an eCCE may be formed from resource element groups that are mapped to resource elements in the time/frequency grid; they may be exemplary called Enhanced Resource Element Groups (eREGs).
FIG. 13 schematically discloses the subframe content regarding PDCCH, ePDCCH and PDSCH, and further illustrates that for the ePDCCH 8 different eREG are exemplary assumed.
At present, there is no agreed definition as to how the resource element to resource element group mapping is going to be for the ePDCCH being in the PDSCH region.
The RE-to-eREG mapping for the ePDCCH (i.e. generally within or at least including REs from the PDSCH region) should allow for a SBFC transmission to achieve diversity, and advantageously should furthermore allow the application of the same mapping regardless of whether a diversity transmission is utilized or not.

Common mapping of resource elements to enhanced resource element groups

Panasonic Intellectual Property Corporation of America


An endorectal trocar provided with body for endorectal introduction that defines open internal channel and leak-tight barrier that extends across internal channel and exhibits passageways for rectoscopy instruments, the body and the leak-tight barrier are two distinct assemblies that can be attached by the fixing elements within the internal channel.

(1) Field of the Invention
The present invention relates to an endorectal trocar. Specifically, it relates to the field of endoscopy and surgery for intervention by the rectal route, for exploratory or therapeutic procedures. In this context, the term trocar is intended in the broad sense as an accessory suitable for introducing various instruments (particularly in endoscopy) through natural cavities, and in the case of the invention, in the rectum through the anus.
(2) Description of Related Art
In this field, very specific devices are generally employed.
A complex ensemble specifically intended for rectoscopy is known from the document FR 2,536,651, which includes a metallic body suitable for being introduced by the rectal route with a plurality of endoscopy instruments, such as a video camera, endorectal inflation system, or the like, arranged within its interior volume. This complex and costly device comprises multiple pieces.
From its design, it is systematically reusable and requires delicate and costly sterilization steps. In addition, a leak-tight seal surrounding the pathway for the instruments is ensured by a sealing ring added to the exterior of the trocar and located behind the channel for introduction through the rectum. This situation offers less clearance for the instruments introduced, and is implemented by a costly assembly means within the body of the instrument and a sealing ring.
There is thus a need to offer an endorectal trocar that provides more effective cooperation between the sealing means inside the channel for introducing the instruments and the body of the trocar device. There is also a need to improve the steps for the placement of the trocar, notably with regard to the phase for introduction through the anus and the general steps for utilizing the trocar, in particular for implementing its fixation, insufflation with an inflation fluid, etc.


A wavelength tunable laser emission device (1) comprises: a first waveguide (31) comprising an optical amplification means for producing a stimulated light emission, the first waveguide extending in a longitudinal direction of the emission device, a second waveguide (5) made of silicon on silicon dioxide and disposed parallel to the first waveguide spaced from the first waveguide in a vertical direction of the emission device so as to allow the existence of a hybrid optical mode coupled at one and the same time to the second waveguide and to the first waveguide, the second waveguide comprising a distributed reflector (9) along the second waveguide, the second waveguide comprising transverse zones (11, 12, 13, 14) doped differently so as to form a polar junction oriented in a transverse direction of the emission device. Electrodes (15, 16) coupled to the doped transverse zones modify an effective index seen by the hybrid optical mode.

Known tunable laser sources are, in particular, Bragg reflector (or DBR standing for Distributed Bragg Reflector) lasers in which the adjustment of the emitted wavelength entails a modification of a phase condition of the longitudinal modes of the DBR cavity. This then results in discontinuous tunability with mode jumps. A phase section of the laser source makes it possible to precisely align a resonant mode of the cavity on the desired wavelength. This results in a device which is relatively complex to adjust, in which a control current for the gain section, at least one control current for the distributed reflector or reflectors and a control current for the phase section must be adjusted simultaneously.
In another solution called a Tunable Twin-Guide (TTG) laser, an active layer of InGaAsP material is situated above a passive Bragg grating of InGaAsP material. Independent control currents are injected, on the one hand into the active layer to adjust the gain, and on the other hand into the passive Bragg grating to adjust the wavelength. Given that the Bragg grating, whose effective index can be modified by current injection, is situated directly in the amplification zone, the resonant modes of the DFB (distributed feedback) type are shifted by the very effect of this adjustment without a phase section being necessary. The wavelength tunability is continuous without any jump of modes.

Commissariat a l'Engerie Atomique et aux Energies Alternatives


A screw feeder is provided for a powder roller compactor machine. The machine includes a hopper for holding powder and a pair of rollers for compacting the powder. A screw feeder transfers powder from the hopper to the rollers. The screw feeder includes an upper tapered section with a tapered shaft and a lower straight section with a straight shaft. Auger flighting is provided on the tapered and straight sections of the screw feeder. The auger flighting preferably has a fixed depth along the length of the screw feeder.

A roller compactor is a well known densification and dry granulation machine for powdered material. The roller compactor produces uniform compacted sheets from powder, with consistent hardness and increased density. The roller compactor compacts powdered material between two rollers under pressure. The compacted powdered sheets can then be used for manufacturing free flowing granules for automatic packaging of products, compact granules for reduced product packing sizes, and granules for high speed tableting or encapsulation, with consistent dust-free purity and size.
In a conventional roller compactor machine, powder material is fed into a hopper and is pre-compacted with a screw feeder in the hopper. The screw feeder than delivers the powder to the rollers. The screw feeder normally is either a fully straight screw or a fully tapered screw, both of which have advantages and disadvantages. A fully straight screw enhances even distribution of the powder onto the compacting rollers. A fully tapered screw enhances pre-compaction and de-aeration of the powder within the hopper.
It is desirable to have a roller compactor machine having the benefits of both the straight screw and tapered screw.
Accordingly, a primary objective of the present invention is the provision of a roller compactor machine having an improved screw feeder.
Another objective of the present invention is the provision of a screw feeder for a roller compactor machine wherein the screw has both a tapered section and a straight section.
A further objective of the present invention is the provision of an improved screw feeder for a roller compactor machine wherein the screw has a tapered shaft and a straight shaft, with constant depth flighting on the shafts.
Still another objective of the present invention is the provision of an improved screw feeder for a roller compactor machine which is economical to manufacture, and durable and safe in use.
These and other objectives will become apparent from the following description of the invention.

Screw feeder for roller compactor machine


A diffuser set for drinks dispensers having delivery groups provided with "post-mix" valves connected to at least two lines for collectively supplying respective drink components, comprising a valve having an output section connected to the "post-mix" valve and at least two input sections provided to receive corresponding drink components to be sent selectively to the output section; and two tubular elements, branched off at least three ways and having respectively first branches connected with corresponding supply lines and second branches taken off the first branch and connected to an input section of the valve in such a way as to send thereto the flow of drink components received from the respective supply lines.

The present invention relates to a diffuser set for chilled drinks dispensers fitted with "post-mix" valves.
In the technical field pertaining to the delivery and distribution of chilled drinks, the use is known in the prior art of drinks dispensers wherein the drink is prepared immediately before being delivered through the mixing of two or more components which, appropriately chilled, are separately taken to the mixing point. More specifically, the dispensers comprise delivery groups which are individually provided with two distinct ducts that feed the post-mix valve and that, in turn, receive the components of the drink from related distinct supply lines. One of these ducts conveys the syrup, whereas the other one conveys either carbonated water (the so-called soda) or flat water, i.e. water that is free of added gases. The soda, mixing with the syrup, dilutes it allowing to prepare a carbonated drink, whereas the flat water allows to prepare a non carbonated drink such as tea.
Each diffuser set also comprises a communication duct allowing for its collective connection together with other similar diffuser sets to the same supply line in order to allow to obtain dispensers fitted with multiple delivery taps.
In the preparation and in the delivery of the chilled drinks, a general problem is represented by the need to maintain the delivery temperature of the drink constantly controlled.
This is obtained by means of refrigerating systems comprising a tank containing a cooling fluid. In the tank are immersed cooling coils through which the components of the drinks are made to flow; after being chilled, the components are conveyed to the aforesaid dispensers along a section of the supply line positioned between the tank and the dispenser itself.
Along this section of line, however, the components of the drink tend to absorb heat from outside and to become warmer. This disadvantageous effect is particularly intensified by delivery stops because if the distribution system remains idle for some time, the carbonated or flat water located in the aforesaid sections of the respective supply lines tends to warm up more easily.
To obviate this, solutions have been sought that entail the creation of a continuous recirculation of a flow of a component of the drink to be mixed with the syrup, for instance soda, which through a particular pump is continuously made to circulate from the chilling tank to the dispenser and vice versa. One possible way to realize this concept can be obtained with the aid of the same diffuser sets provided for "post-mix" valves. Therein, a flow of carbonated or flat water is made continuously to transit through the duct joining the various diffuser sets of the same dispenser, chilling them even during stops in the delivery of the drinks.
The sets thus obtained require, however, rather costly and cumbersome pumps and thus only one unit is provided for each chilling tank regardless of the number of coils contained, or in other words, regardless of the number of different components of the drink which are conveyed to the dispenser.
Under such conditions, diffuser sets known in the prior art, having available only one duct for the possible continuous recirculation of the chilled soda or of the chilled flat water, in practice do not allow to obtain chilled drink dispensers able to deliver heterogeneous drinks, meaning by that the ability to deliver carbonated drinks through a certain group of delivery taps and flat drinks through other groups of taps.
Moreover, diffuser sets known in the prior art, although used to obtain dispensers able to deliver exclusively drinks of a single type, all carbonated or all flat, do not allow to eliminate the recirculation of at least one of the components of the drink. At least one of the diffuser sets, if not all, must provide for the possibility of recirculating a component of the drink towards the chilling tank, if the risk of delivering drinks at less than optimal temperatures is to be avoided, at least for a certain time interval after a stop in the distribution system.

Diffuser set chilled drinks dispensers fitted with post-mix valves


The invention provides a production method for stabilizers which produces with high productivity in a compact production line, without tempering. The production method for stabilizers of the invention includes: forming a steel bar material containing at least C: 0.15 wt % to 0.39 wt %, Mn, B and Fe into a product shape by bending; and quenching the bent steel bar material in a medium having a heat transfer coefficient higher than or close to that of water.

A vehicle such as an automobile is provided with stabilizers (stabilizer bars or anti-roll bars) which suppress roll of a vehicle body due to vertical displacement of wheels. The stabilizer is generally a bar in a substantial U-shape and includes a torsion portion extending in a lateral direction and a pair of right and left arm portions which are bent in a longitudinal direction of the vehicle. In the vehicle, the distal ends of the arm portions in the stabilizer are coupled to respective suspensions and the torsion portion is inserted into bushings fixed on the vehicle body, to support the stabilizer in a suspended manner between the right and left suspensions.
When the vehicle that is traveling makes a turn or travels on an undulating road, a stroke difference occurs between the right and left suspensions due to the vertical displacement of the right and left wheels. In this case, each arm portion of the stabilizer receives a load (displacement) caused by the stroke difference between the suspensions, which distorts the torsion portion by the load (displacement difference) from each arm portion. The torsion portion generates elastic force to recover the distorted deformation. The stabilizer increases roll stiffness of the vehicle body to suppress the vertical displacement difference between the right and left wheels by the elastic force for recovering the distorted deformation, which suppresses the roll of the vehicle body.
There are two configurations of the stabilizer, that is, a hollow stabilizer having a hollow structure, and a solid structure having a solid structure. The hollow stabilizer contributes to weight reduction of the vehicle body, but its manufacturing cost is relatively high because a raw material is used such as an electric resistance welded steel pipe or a solid-drawn steel pipe. In contrast, the solid stabilizer is superior in a mechanical strength and a manufacturing cost.
Conventionally, the stabilizer is generally made of a carbon steel such as S48C (JIS standard) or a spring steel such as SUP9 (JIS standard) and SUP9A (JIS standard) which has a good mechanical strength such as a tensile strength and a good fatigue resistance. The solid stabilizer is often produced by heating or cooling to be bent for forming a hot rolled steel bar or a cold rolled steel bar made of the material described above in a product shape, and then by heating the bent workpiece. The heating process includes quenching and tempering. Oil quenching is frequently used as quenching. A semi-finished product of the stabilizer after the heating process is usually subjected to a surface treatment by shot-peening and a finishing process such as coating to be a final product.
As an example of a production line to produce a stabilizer through the oil quenching and tempering, for example, Patent Document 1 discloses a stabilizer bar production line including a heating furnace for heating a spring steel wire, a stabilizer bar producing device for bending the spring steel wire heated in the heating furnace to produce a stabilizer bar, a quenching tank for quenching the produced stabilizer bar in quenching oil, a cleaning device for cleaning the quenched stabilizer bar, and a tempering furnace for tempering the cleaned stabilizer bar (see paragraphs 0021, 0022, etc.).

This patent is subject to a terminal disclaimer.


A mount for a semiconductor device includes a carrier, at least two metal leads disposed on a bottom surface of the carrier, and a cavity extending through a thickness of the carrier to expose a portion of the top surfaces of the metal leads. A semiconductor light emitting device is positioned in the cavity and is electrically and physically connected to the metal leads. The carrier may be, for example, silicon, and the leads may be multilayer structures, for example a thin gold layer connected to a thick copper layer.

1. Field of Invention
The present invention is directed to a mount for a semiconductor light emitting device such as a light emitting diode.
2. Description of Related Art
Semiconductor light emitting devices such as light emitting diodes (LEDs) are among the most efficient light sources currently available. Material systems currently of interest in the manufacture of high brightness LEDs capable of operation across the visible spectrum include group III-V semiconductors, particularly binary, ternary, and quaternary alloys of gallium, aluminum, indium, and nitrogen, also referred to as III-nitride materials; and binary, ternary, and quaternary alloys of gallium, aluminum, indium, arsenic, and phosphorus. Often III-nitride devices are epitaxially grown on sapphire, silicon carbide, or III-nitride substrates and III-phosphide devices are epitaxially grown on gallium arsenide by metal organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), or other epitaxial techniques. Often, an n-type region is deposited on the substrate, then an active region is deposited on the n-type region, then a p-type region is deposited on the active region. The order of the layers may be reversed such that the p-type region is adjacent to the substrate.
Such devices are often mounted on mounts which provide electrical and mechanical connection between the semiconductor device and the larger system in which the device is included. Such mounts are often silicon. Since the mount is the primary thermal path for heat removal from the semiconductor device, the mount may be designed for high thermal conductivity. As semiconductor light emitting devices are operated at higher power, silicon mounts become increasingly incapable of efficiently dissipating the heat generated in the device. Needed in the art are mounts which provide low thermal resistance in addition to being inexpensive, easy to handle, and easy to manufacture.

Mount for a semiconductor light emitting device


In a hand-held electrical grinder with a tool holder (22) driven by a rotating eccentric plug (20) which, for receiving a grinding tool has a quick-action locking device (24) with locking elements (40, 41) fixed on the tool and tool holder sides and corresponding with each other, the locking elements (40) on the tool side are formed, on the one hand, by hooks (42) disposed on a circular line and, on the other hand, the locking elements (41) on the holder side are realized by means of a spring wire (43), which is bent in the shape of a ring, in order to transmit a greater output from the tool holder (22) to the (10). The spring wire (43) has a number of radially inward directed indentations (431) corresponding to the number of the hooks (42) on the tool side, which extend behind the hooks (42) on the tool side for locking the grinding tool (10) in.

The invention relates to a hand-held electrical grinder.
In connection with known hand-held electrical grinders of this type with a grinding tool embodied as a triangularly-shaped grinding plate (EP 0 610 801 A1), the locking elements of the quick-action locking device on the holder side have a bar which is of one piece with the operating key, which can be displaced against the force of a pressure spring and which has a recess with two inclined faces constituting a locking protrusion. The locking elements on the tool side are constituted by at least one detent hook, which is formed in one piece from the grinding plate and projects upward from it. With the grinding plate placed on the support face of the tool holder, the detent hook projects into the recess of the tool holder and the locking protrusion grips behind it under the force of the pressure spring. In order to be able to place the symmetrical grinding plate into the tool holder in arbitrary positions, respectively turned by 120.degree., a detent hook is arranged in each one of the three corners of the grinding plate. The interlocking elements arrested on the tool side are constituted by support claws, which are disposed in pairs in each corner of the grinding plate symmetrically in respect to the detent hook, while the corresponding interlocking elements fixed on the holder side are realized by means of two insertion openings, which are arranged on the side of the tool holder opposite the operating key. The operating key is displaced against the force of the spring for changing the grinding tool, because of which the detent protrusion releases the detent hook. Now the grinding plate can be manually pulled off the tool holder. When the grinding plate is reinserted, two of the support claws are inserted into the two insertion openings in the tool holder, and the grinding tool is pressed onto the support surface of the tool holder. In the course thereof the bar is pushed against the force of the pressure spring over the lower run-up inclination at the locking protrusion until the detent hook slides past the locking protrusion. The bar, which then springs back, pushes the locking protrusion behind the detent hook, by means of which the grinding tool is fixed immovably on the tool holder in the axial direction.


A method of isolating scan paths in an integrated circuit to reduce the RC delay associated with the scan paths and reduce power consumption, and to further enhance the capacitive decoupling of the power supply to reduce noise. The scan path can be connected to a data-storage element (latch or flip-flop) by a CMOS transmission gate, a single PMOS or NMOS transistor, or a logic gate (such as a NAND gate). The data-storage element is tested using either a scan-enable line, or the scan clock which is also connected to the data-storage element as an input. When the scan-enable line (or scan clock) is turned on, the scan path is connected to the output of the data-storage element.

1. Field of the Invention
The present invention generally relates to integrated circuits and, more particularly, to a method of isolating scan paths used for testing logic designs.
2. Description of the Prior Art
Integrated circuits are used in a wide variety of products, and many of these circuits, such as microprocessors, adapter chips, etc., have complicated logic designs. These designs are often buried in the microchip layers and can be difficult to test. A generalized integrated circuit is shown in FIG. 1. Circuit 10 includes several logic function circuits 12, 14, 16, and 18 and several flip-flops, or latches, 20, 22, 24, 26, and 28. The logic functions have various inputs, and their outputs are connected to various latches; for example, logic function 12 has four outputs respectively connected to latches 20-26. Each logic function has many logic components (gates, inverters, etc.) arranged to provide a particular function, such as an adder or execution unit. The latches store data, and may provide inputs to other logic functions, such as latches 20 and 24 which are connected to logic function 16. Circuit 10 may have one or more latches such as 28, which provides the output of the circuit. A clock signal 30 provides synchronization (control) for the latches. The clock may be a primary input to the circuit or internally generated.
Those skilled in the art will appreciate that, in this example, the circuit is greatly simplified since there are many more logic functions and latches in a typical integrated circuit, the logic functions can further be very complicated, and more than one clock signal can be provided. This figure is still adequate, however, for understanding how testing of the circuit can be performed. One method involves the use of test patterns which are fed into the primary inputs of the circuit while the output is examined. This approach is limited by the structure of the logic design and may fail to catch unusual flaws in a particular design.
Another testing approach is to provide a mechanism for setting the latches to predefined states using special lines which are provided on the microchip, such as scan line 32 which is connected directly to latch 20, and scan line 34 which directly interconnects latch 20 with latch 28 (other scan lines, not shown, can be provided for other latches, depending upon the type of scan implementation). Separate control can be provided for scanning the latches, using a test clock 36. A scan output line 38 may also be provided. Conventional scan designs include the multiplexed D Flip-Flop scan design, and IBM's Level Sensitive Scan Design (LSSD). See also U.S. Pat. Nos. 4,698,588, 4,782,283, and 5,032,783.
Logic designs using such scan techniques suffer some system delay penalty due to the extra loading on the latches/flip-flops which arise from the scan path wires. In other words, it takes longer for the output of the latch to change its state because of the required charging (or discharging) of the scan lines; this delay is a function of the RC constant of the wire. The delay occurs whether the system is being tested or not, i.e., the loads are not needed for normal system function, and so, it slows down normal operation of the circuit. Conversely, if the circuit is run at a very high clock speed, logic errors may occur.
Additional problems arise from scan paths, such as excess power consumption and power-supply noise due to varying switching activity (between high and low states) during circuit operation. Scan path switching (from zero to one or one to zero) unnecessarily adds to circuit power consumption and power-supply noise. It would, therefore, be desirable to devise a method of isolating the scan paths during normal circuit operation so as to not slow down performance, and it would be particularly advantageous if the method also reduced power consumption and unnecessary switching noise. Techniques such as those shown in U.S. Pat. No. 4,495,629 achieve some of these objectives, but require modifying system scannable storage elements, which can introduce additional limitations.

International Business Machines Corporation


A wireless terminal includes an RF transceiver, an auto tuner, and an antenna. When a remote signal is received at the wireless terminal, the auto tuner is adjusted in accordance with the received signal to optimize OTA performance of the wireless terminal. As further remote signals are received by the wireless terminal, the tuner is readjusted. As a user inputs information to be transmitted, the tuner is also readjusted in accordance with the transmission signals to optimize OTA performance of the wireless terminal, and a best compromise between the TX OTA performance and the RX OTA performance is calculated. Current/temperature information may also be obtained for readjusting the tuner.

The present disclosure relates to wireless communication devices, more particularly to optimizing over the air (OTA) performance of a wireless terminal.
Wireless terminal OTA performance requirements get tougher each year. Today, many companies are developing auto antenna tuners for the wireless industry. These tuners "map" the natural antenna impedance to another value that better suits the radio. This process is known as antenna matching.
The prior art methods for antenna matching focus on optimization of the transmission (TX) path performance. The TX mode antenna impedance is actively transformed back to the "ideal" 50 Ohm port impedance. The receiving (RX) mode performance is assumed to improve during optimization of the TX mode.
There are three main problems with the prior art approach. First, the TX system OTA performance, which is indicated by desired total radiated power (TRP), low battery current (Ibatt), and low operating phone temperature, may not optimize at 50 Ohms. Second, the RX system OTA performance, which is indicated by total isotropic sensitivity (TIS), may not achieve an optimum performance level with a TX mode derived antenna match. Given a typical antenna, the RX frequency band impedance is quite different when compared to the TX frequency band antenna impedance. Thus, there is no guarantee that the RX system will achieve optimum performance with a TX only derived auto-tuner match. Third, prior art tuning does not address the safety aspects associated with auto tuning methods. Safety issues include excessive generated heat (thermal issues), excessive battery current, and excessive output power (very high TRP).
Accordingly, a need exists for optimizing the RX mode OTA performance of a wireless terminal. A further need exists for simultaneously optimizing the TX mode OTA performance and the RX mode OTA performance of a wireless terminal. An additional need exists for controlling the maximum radiated power (TRP), the maximum phone temperature, and the maximum phone battery current (Ibatt).

Full closed loop auto antenna tuning for wireless communications


A new and distinct cultivar of Alstroemeria plant named Capri, having an unusually attractive predominantly white flower with outer petals having green tips and lavender-pink brush stroke patterns in the central basal portions and inner petals which are white with faintly lavender-pink shadings and patterns of numerous purple stripes on the top two inner petals, and few purple stripes confined to the apical portion of the bottom inner petal.

The present invention comprises a new and distinct cultivar of Alstroemeria plant referred to by the cultivar name Capri. Capri was originated from a hybridization program in Roelofarendsveen, The Netherlands in 1985. The female parent was an unnamed proprietary hybrid which was developed and is maintained by me for the sole use in planned breeding programs. The male parent was a cultivar named Flamingo. It is unknown to me if Flamingo has been patented in the U.S.A. Capri was discovered and selected as one flowering plant within the progeny of the stated parentage by me on Jul. 12, 1985 in a controlled environment in Roelofarendsveen, The Netherlands. The first asexual reproduction of Capri was accomplished when vegative cuttings were taken from initial selection on Nov. 6, 1985 in a controlled environment in Roelofarendsveen in The Netherlands. Horticultural examination of selected units initiated in November 1985 has demonstrated that the combination of characteristics as herein disclosed for Capri are firmly fixed and retained through generations of asexual reproduction. The following observations, measurements and comparisons describe plants grown in Roelofarendsveen, The Netherlands under greenhouse conditions which approximate those generally used in commercial practice. The following traits have been repeatedly observed and are determined to be basic characteristics of Capri, which in combination distinguish this Alstroemeria from its parents and all other varieties of which I am aware:
1. The outer petals have an attractive, nearly white appearance which is interrupted by the green color of the tips which radiates from the tips along the central veins of each outer petal, fading to white. Along the same veins, between the attachment points and the green of the tips of these petals are brush strokes of shades of lavender-pink which compliment the green portions in shape. The remaining marginal areas of the outer petals contrastingly appear to be stark white. PA0 2. The inner petals are characterized by an unusual combination of colors and pattern of stripes. The three inner petals have a predominant white ground color which is slightly blushed with a hint of lavender-pink. The two top inner petals have numerous stripes of deep purple in a uniform pattern with stripes increasing in length and width from the attachment point to the apex of these petals. The lower, inner petal is substantially white and has a few stripes of deep purple confined to the apical portions of this petal. PA0 3. The soft, complimentary coloration of the petals of the flowers of this plant give striking and attractive distinction to this variety which has not been seen in previous plants of this market class.


According to a disclosed embodiment, a flow indication counter is incremented each time a data packet is transmitted from a buffer. When the number of data packets transmitted equals or exceeds a threshold number, a flow indication message comprising the buffer window size is generated and transmitted to the base station controller. Further, flow indication messages can be generated and transmitted every threshold time interval, independently of the number of data packets transmitted to ensure that flow indication messages are sent at least every preset time interval. Moreover, a system for flow control can be constructed comprising a flow indication counter module configured to provide an updated number of data packets transmitted. The system further comprises a window size monitoring module which determines the buffer window size and a message generating module which generates a flow indication message comprising the buffer window size.

1. Field
The present invention generally relates to the field of wireless communication systems, and more specifically to flow control between a base station controller and a base transceiver station.
2. Background
High Data Rate ("HDR") technology is a high-speed, high-capacity wireless technology optimized for packet data services. Using a single, data-dedicated 1.25 MHz channel for operation, HDR can deliver data at a peak data rate of 2.4 Mbps, which is significantly faster than many accesses provided over landline networks. Thus, the advantages of HDR include, among others, high-speed data transmission and high spectral efficiency.
HDR is the basis for the 1x Evolution Data Only (1xEV-DO) standard, which has been standardized by the Telecommunications Industry Association as TIA/EIA/IS-856. HDR is designed to be interoperable with existing wireless communication systems, for example a code division multiple access ("CDMA") system. In CDMA systems, each signal is separated from those of other users by coding the signal. Each user uniquely encodes its information signal into a transmission signal, which is then transmitted over a 1.25 MHz channel. The intended receiver, knowing the code sequences of the user, can decode the transmission signal to receive the information. The fact that a CDMA channel is 1.25 MHz simplifies the integration of HDR technology into the present CDMA framework.
Using CDMA for illustrative purposes, HDR technology can utilize existing CDMA infrastructure and architecture, including CDMA base station controllers ("BSC") and base transceiver stations ("BTS"). For example, in a CDMA system configured to be interoperable with HDR technology, data downloaded from the Internet by a user is routed through the BSC to the BTS, which transmits the data to the user via a data-dedicated 1.25 MHz channel or air-link. The BSC packetizes the stream of data it receives into individual 128 byte HDR packets (or "data packets") before transmitting the data packets to the BTS. The data packets are received by the BTS and placed in a buffer (or "queue") of fixed size to be transmitted to the user using an HDR protocol.
To reduce the possibility of overflowing or overrunning the buffer at the BTS, i.e., the BTS receiving more data from the BSC than the buffer can accommodate and/or transmit to the user, as well as the possibility of "starving" the buffer, i.e., the BTS not receiving data from the BSC when the buffer is empty, mechanisms to control the data flow between the BSC and the BTS are commonly employed. Generally, flow control mechanisms are based on the BTS advertising to the BSC the amount of space, or "window," available at the buffer for receiving more data in order for the BSC to determine how much data to transmit to the BTS.
One conventional method for flow control between the BSC and the BTS involves the BTS advertising its window size to the BSC at certain, preset, buffer capacity threshold points. For example, when the buffer nears capacity and reaches a preset high watermark threshold, the flow control mechanism is triggered, and the BTS sends a signal informing the BSC to stop transmitting additional data packets so as not to overrun the buffer. Overrunning the buffer can lead to problems such as data packets being dropped and lost at the buffer and having to be retransmitted, leading to less reliable data transmission. Further, having to retransmit dropped or lost data means incurring more overhead and slowing of communication. In the other instance when the buffer is nearing empty and hits a preset low watermark threshold, the flow control mechanism is triggered, and the BTS sends a signal telling the BSC to send more data packets. An empty buffer translates to wasted system resources, because it can result in frames of unused air-link that could be utilized to transmit data from the buffer.
A drawback to the conventional flow control mechanism described above is that feedback signals may not be received by the BSC in time to prevent overrunning and/or starving the buffer. For instance, by the time the BSC receives a signal from the BTS to stop sending more data, the BSC may have already put too much data "in flight" to avoid overrunning the buffer, leading to data packets being dropped at the buffer. In the case of an emptying buffer, a signal to send more data may not be received by the BSC in time for it to get data to the buffer before the buffer is completely empty, resulting in wasted air-link frames. Further, a flow control mechanism which is triggered by buffer capacity threshold points may result in the transmission of a high number of feedback signals which puts more strain on the system and increases system overhead.
There is thus a need in the art for an improved method for flow control between BSC and BTS. More particularly, there is a need for a method to reduce the likelihood of data overrun at a buffer, as well as the possibility of a starving buffer.

Method and system for flow control between a base station controller and a base transceiver station


A device for connecting an injection needle to an injection apparatus, wherein the device provides a plurality of possible points of contact in at least two planes, and wherein the points of contact have associated spring forces for acting generally perpendicularly on the injection apparatus.

In ambulatory medicine, reusable injection apparatus or devices for subcutaneously administering liquid medicines are increasingly being used instead of disposable syringes.
One example of such reusable injection apparatus is injection pens which dispense a medicine in a desired amount from a pre-filled ampoule by means of a dosing means. Typically, for each injection, a new injection needle is placed on the injection pen and removed after it has been used. The needle is a hollow needle for conducting medicine from a storage container into the user's or patient's body.
Despite certain standards for injection apparatus, manufacturers prefer to develop injection apparatus which are only suitable specifically for their medicines. Thus, practically all such injection apparatus have a specific fixing device for the needle, which therefore does not fit or only insecurely fits onto another model or device. The needle is securely fixed on an injection pen when it neither slips nor tilts out of the perpendicular. An insecurely fixed needle increases the risk of injuries or needle breakage. If a physician or patient requires a number of medicines or injection apparatus for a treatment, they are furthermore reliant on a corresponding variety of needles, which makes the needles more difficult to obtain and store and, in smaller amounts, makes them more expensive.
Consequently, a fixing device has been sought for injection needles which securely and detachably fixes a needle on different models of injection apparatus, in particular on standard commercial injection pens having a thread or thread segments for detachably fixing or connecting the needle.
Fixing devices for injection needles, for pushing or screwing the needle onto the thread or thread segment, are known from documents WO 95/01812 and GB 737,676. A typical fixing device has the shape of a cap with one open end and one closed end which holds the needle perpendicularly in the middle. At least one elevation or recess, for example a cam, thread or thread segment, is situated on the inner side of the surface areas of the cap and snaps into the flight of the complementary thread or thread segment of the injection pen or is screwed in by being turned. The fixing devices of the above-cited patent specifications typically have cams which taper towards the thread with a pitch which is adapted to the thread, such that—when pushed onto a thread with a different pitch—the cap undesirably tilts out of the perpendicular if the cams engage with the flight.
To prevent tilting, at least three points of contacts are needed between the inner side of the cap or its cams and the thread of the injection pen, wherein said points of contacts are not in the same plane and furthermore hold the cap in the perpendicular. This means that, once pushed on, these points of contacts must no longer shift, otherwise the needle slips along the direction of the needle.
Although not provided for injection pens, U.S. Pat. Nos. 2,894,509 and 2,828,743 describe fixing devices comprising cams or grooves, which—independently of the pitch of the thread—are not in the same plane and enable two fixed positions and a defined shift of a needle. However, the solution from U.S. Pat. No. 2,828,743, with grooves which practically encompass the whole circumference, is not suitable for detachably pushing or screwing onto a thread. The solution from FIGS. 2 and 3 of U.S. Pat. No. 2,894,509 is only suitable for a thread or thread segments if the cams engage uniformly, secured against slipping, with the flights, which given the different dimensions of the threads is rarely the case.
In specific cases, the cap can also tilt out of the perpendicular, the upper or lower pair of cams describing a tilt axis. Consequently, more cams would be necessary to counteract this tilting symmetry. More cams furthermore provide the advantage that, through more points of contact, the clamping force in these points can be smaller for the same adherence of the cap or needle on the injection pen. The clamping force corresponds to a spring force which is predominantly determined by the geometry of the cams, the arrangement on the surface area of the cap and the elasticity of the materials. A smaller clamping force therefore allows, for the same spring force, a larger spring path of the cam or the surface area of the cap. Consequently, such a cap would fit onto correspondingly larger or smaller thread diameters, providing the clamping force always acts the same way, preferably perpendicularly, on the thread of the injection pen.
None of the known fixing devices for injection needles show a solution in which the spring forces in the points of contact always act the same way, in particular perpendicularly, on the thread, if the spring path is increased. This would be the case if the cams were attached in the middle of spring-elastic elements which were each connected to the rigid surface area via an end, analogously to a three-point bending element. Doubling the points of contact, in order to enable a larger spring path of the cams for equally larger differences in the diameters of the threads, required as least twice as much space on the inner side of the surface area of the cap. In the known solutions, with up to five cams at most, this is a very complicated design or cannot be solved at all, when the cams have to be arranged in different planes if the cap is not to tilt out of the perpendicular.


A jitter detection method and apparatus for informing an adaptive equalizer that the correlated jitter of transmitted data exceeds a predetermined jitter value. In one embodiment of the present invention, a jitter detection circuit receives transmitted data symbol pulses and clock signal pulses. The jitter detection circuit then compares a specified edge (e.g., the falling edge) of an incoming data pulse with the corresponding specified edge (e.g., the falling edge) of a clock signal pulse to determine if an original phase error between the incoming data pulse and the clock pulse exists. Similarly, the jitter detection circuit detect subsequent phase errors between subsequent data pulses and subsequent clock pulses. The original detected phase error will then be compared against subsequently detected phase errors. Based on this comparison of the phase errors, the jitter detection circuit then informs the adaptive equalizer of the degree of phase and amplitude compensation that it needs to provide.

1. Field of the Invention
The present invention relates to the field of data communication, and particularly to a jitter detection method and apparatus.
2. Description of the Related Art
Communication networks are commonly used to interconnect a variety of computing devices. These networks typically include a number of communication nodes that transmit data from their encoders to their decoders across a variety of transmission media. For example, a number of communication protocols (such as the Ethernet protocol and the Token Ring protocol) utilize twisted pair cables (such as category three unshielded twisted pair cables (UTDCAT3)) to transmit data from their encoder to their decoder.
Transmission of data across transmission media causes the phase and amplitude of the data to be distorted. Amplitude and phase distortions in turn can cause decoders to erroneously predict the value of the received data. For example, phase distortions can cause correlated jitters (i.e., can cause phase-related abrupt spurious variations in the phase of successive received data symbol pulses with respect to the phase of a continuous reference clock), which reduce the probability that demodulators of the decoders will accurately predict the value of the received data by preventing the demodulators from sampling the received signals at the center of the data symbol pulses.
Numerous prior art equalizers have been developed to compensate for phase and amplitude degradations of the transmitted data. For example, prior art equalizers include analog discrete equalizers and digital equalizers (such as automatic line build-out, finite impulse response (FIR), and infinite impulse response (IIR) equalizers). In addition, a number of these prior art equalizers adjust their equalization adaptively. In other words, a number of these equalizers increase their phase and amplitude compensation as the phase and amplitude distortions of the transmitted data increases. One example of an equalizer that adaptively adjusts its phase and amplitude compensation is disclosed in the U.S. Patent Application Ser. No. 08/414,618, filed Mar. 31, 1995, entitled "A Quasi-Adaptive Analog Equalization Method And Apparatus," now U.S. Pat. No. 5,717,716.
Furthermore, in order to ascertain when additional phase and amplitude compensation is needed to oppose the increasing phase and amplitude distortions, some adaptive equalization schemes (such as the equalization scheme disclosed by the above-noted patent application) utilize jitter detection circuits for determining when phase distortions exceed predetermined maximum values. Consequently, there is a need for an innovative jitter detection method and apparatus for detecting when the correlated jitter of the transmitted data exceeds a maximum tolerable value in order to inform an adaptive equalizer to adjust its phase and amplitude compensation.


A diaphragm and a speaker unit which can prevent generation of abnormal sound by suppressing rolling phenomenon. The speaker unit has a diaphragm. The diaphragm includes a portion for supporting a voice coil, and a sound emitting portion formed continuously to one end thereof. The voice coil supporting portion has a shape extending reversely to the sound emitting direction. The sound emitting portion includes a step portion having a surface substantially perpendicular to the sound emitting direction, and a bent portion having a cross-section bent toward the inside of the voice coil supporting portion from one end of the step portion. Consequently, the voice coil supporting portion is movable to describe an arc having a radius substantially equal to the radius of curvature at the bent portion of the voice coil supporting portion and a basic point substantially identical to the center of the bent portion in the bending direction as the voice coil moves in the sound emitting direction or in the reverse direction. Rolling phenomenon can thereby be retarded, the voice coil supporting portion can be prevented from colliding against a magnetic circuit when the speaker unit is driven and generation of abnormal sound can be prevented.

Conventionally, there is known a riffel-type speaker configured to include a rectangular diaphragm and a linear voice coil arranged at the center of the diaphragm. For example, a speaker having a configuration of this kind is disclosed in a Patent Reference 1.
The speaker disclosed in the Patent Reference 1 includes: an upper and a lower magnetic circuits providing magnetic gaps parallel with each other and having opposite magnetic flux directions; a frame connected to the magnetic circuits and having an U-shaped section; a diaphragm supporting a voice coil substantially at its center and having an outer circumference supported by the frame; and a damper arranged below the voice coil and having an outer circumference attached to the frame. By this configuration, the minimum resonance frequency f0 can be lowered even if an elongated configuration with a narrow lateral width is employed, thereby improving the sound pressure characteristic.
Patent Reference 1: Japanese Patent Application Laid-open under No. H11-187484


A shoe includes an upper and a sole. The upper includes an outer layer having a first knitwear and an inner layer having a second knitwear. The first knitwear differs from the second knitwear with regard to at least one of a yarn used, a stitch structure, an alignment, and a form.

In general, a shoe comprises an outer sole and an upper, which is attached to it. In particular, sports shoes further comprise in general a midsole, which is arranged between the upper and the outer sole, which is also called middle sole. The upper, the outer sole, and (as far as existing) the midsole are made of leather in classical shoes, and (as a general rule) are made of synthetic materials in sports shoes.
In particular, the uppers of sports shoes are often provided with specific functions. For instance, the outer surface of an upper may be required to be as water-repellent as possible. At the same time, the upper may need to be permeable to air, so that it is possible to provide air from outside to the foot. Furthermore, it may desirable that humidity is to be transferred away from the foot quickly. Besides these requirements, a shoe, in particular a sports shoe, is to provide optimum support without overly constricting the foot, i.e. the shoe is to be comfortable to wear.
Thus, the present invention is based on the problem of providing an upper for a shoe, in particular a sports shoe, which meets the above-mentioned requirements while being simple and cost-effective to manufacture.


A method of manufacturing a flip-chip nitride semiconductor light emitting element includes steps of providing a nitride semiconductor light emitting element structure; forming an insulating protective layer on the nitride semiconductor light emitting element structure; forming a resist pattern having openings above an n-side electrode connecting surface and a p-side electrode connecting surface; etching the protective layer to expose the n-side electrode connecting surface and the p-side electrode connecting surface using the resist pattern as a mask; forming a first metal layer that becomes an n-side electrode and a p-side electrode, the first metal layer being formed as a continuous layer disposed on the n-side electrode connecting surface, the p-side electrode connecting surface and the resist pattern; forming a second metal layer that becomes metal bumps by electrolytic plating using the first metal layer as an electrode for the electrolytic plating; and removing the resist pattern.

1. Field of the Invention
The present invention relates to a nitride semiconductor light emitting element mounted on a mounting substrate via a metal bump and a manufacturing technique of the nitride semiconductor light emitting element.
2. Description of the Related Art
Nitride semiconductors are generally used for light emitting elements such as light emitting diodes (LED) and laser diodes (LD), light receiving elements such as solar cells and light sensors, and electronic devices such as transistors and power devices. Especially, the light emitting diode (nitride semiconductor light emitting element) using the nitride semiconductor has been widely employed in various light sources for backlight, illumination, traffic signals, large displays and the like.
Examples of a method of mounting such nitride semiconductor light emitting element on the mounting substrate include a flip-chip mounting method in which a semiconductor layer of the light emitting element is oriented downward and a p-side electrode and an n-side electrode of the light emitting element are opposed to each other and connected to wiring electrodes on the mounting substrate.
The nitride semiconductor light emitting element used in the flip-chip mounting method includes an n-type nitride semiconductor layer and a p-type nitride semiconductor layer, each containing an active layer, that are formed on a sapphire substrate or the like, and a p-side electrode and an n-side electrode that are connected to the n-type nitride semiconductor layer and the p-type nitride semiconductor layer, respectively, and are formed on a same plane side as the substrate. The nitride semiconductor light emitting element can be mounted on the mounting substrate by orienting the p-type nitride semiconductor layer and the n-type nitride semiconductor layer downward to allow the p-side electrode and the n-side electrode to be opposed to the wiring electrodes on the mounting substrate and connecting the electrodes to the wiring electrodes through metal bumps by pressing contact.
The method disclosed in JP-A-2004-153110 discloses, as a method of forming metal bumps in the nitride semiconductor light emitting element, a method in which a resist pattern that masks a p-side electrode and an n-side electrode as pad electrodes made of a metal film, except for upper surfaces of both the electrodes, is formed and a metal bump layer is laminated by electroless plating and then the resist pattern is released.
According to another method disclosed in JP-A-2005-79551, a p-side electrode and an n-side electrode each are formed of a metal film, a metal layer is laminated on the entire surface of a light emitting element and a resist pattern having openings above both the electrodes is formed. Using the above-mentioned metal layer as a seed electrode, a metal bump layer is formed by electrolytic plating and then releasing a resist pattern and removing the metal layer except for the electrode surface on which the metal bump layer is laminated.
A method of manufacturing the nitride semiconductor light emitting element having metal bumps according to the prior art (for example, JP-A-2005-79551) will be described with reference to FIG. 15. FIG. 15 are schematic sectional views for describing a manufacturing process of the semiconductor light emitting element having the metal bumps according to the prior art. As shown in FIG. 15, the process includes following steps of (a) forming electrodes on a GaN-based light emitting element wafer, (b) forming insulating films, (c) forming a metal layer on an entire surface, (d) resist patterning, (e) forming bumps by electroplating, (f) removing resists, (g) removing the metal layer, (h) bonding to a submount member-side wafer and (i) separating into light emitting element units.
First, a plurality of light emitting element units 121 each including an n-side electrode 103 and a p-side electrode 104 are formed on a substantial entire surface of a wafer 120 formed by growing a GaN-based compound semiconductor on a surface of a sapphire substrate (not shown) in a matrix (FIG. 15A), and insulating films 122 formed of SiO2 films are formed on portions other than portions where the bumps for the n-side electrode 103 and the p-side electrode 104 are formed (FIG. 15B).
Next, a flat metal layer 105 that is made of an Au/Ti alloy and is electrically connected to the n-side electrode 103 and the p-side electrode 104 is formed on the entire surface of the wafer 120 (FIG. 15C). The metal layer 105 is formed so as to have a thickness of 0.5 to 3 μm by vapor deposition, sputtering or the like.
By forming resists 123 on the metal layer 105 (FIG. 15D) and applying electroplating thereto, bumps 106, 107 are formed on the metal layer 105 (FIG. 15E).
By removing the resists 123 (FIG. 15F) and further removing exposed portions of the metal layer 105, there is obtained a light emitting element-side wafer in which the light emitting element units 121 each having the bump 106 in electrical connection with the n-side electrode 103 and the bump 107 in electrical connection with the p-side electrode 104 are formed in a matrix (FIG. 15G).
Patent document 1: JP-A-2004-153110
Patent document 2: JP-A-2005-79551
However, according to the method of forming the metal bumps using electroless plating as described in Patent document 1 (JP-A-2004-153110), it is difficult to stably form a thick metal bump. According to the method of forming the metal layer 105 by vapor deposition, sputtering or the like as described in Patent document 2 (JP-A-2005-79551), it was difficult to form the flat metal layer 105. In addition, in the step of removing the exposed portions of the metal layer 105, there was a possibility that the metal layer 105 cannot be sufficiently removed to case leakage between the electrodes.

Method of manufacturing nitride semiconductor light emitting element having thick metal bump


A control unit for a battery-operated device is proposed which via an existing control connection recognizes an overload of the battery and/or of the electric device. The control connection of a temperature-dependent resistor is used, which is thermally connected to the rechargeable battery. This connection, which is typically usable to control a charging unit, now serves during the battery operation of the electric device as a control output for monitoring the battery temperature. Since the temperature gradient is also detected, this signal can also be used to monitor the overload of the electric device, which for instance is an electric motor.

It is known that battery-operated devices that are equipped with rechargeable batteries are, connected to a charging unit for recharging the battery. The charging units are often equipped in such a way that they can be used for fast charging of the battery. In fast battery charging, however, considerable heating of the battery occurs toward the end of the charging process, to indicate that the battery is charged. A temperature sensor is connected to the battery by a thermal coupling to protect the battery against damage, such as overcharging. The temperature sensor detects the battery temperature so that the charging unit is turned off once a limit temperature is reached.
In practice, this means that charging the battery requires at least a third line, which leads to a corresponding control input to the charging unit. During battery operation of the electric unit, this control line is not needed.
From German Patent Application 25 20 599 (A1), assigned to General Electric Co. a circuit arrangement for charging storage batteries is known in which the temperature of both the storage battery and its surroundings is measured The charging current is determined as a function of the temperature difference.
From British Patent 2,088,158, corresponding to U.S. Pat. No. 4,507,368 a battery unit is known in which a bimetallic switch is thermally coupled to the battery, and when a temperature limit value is reached, it can interrupt the current circuit to the battery, both in charging and discharging operation.

Control unit for battery-operated device


Provided is an optical layered body which sufficiently suppresses generation of interference fringes and curls, can make a hard coat layer thin, and prevent an increase in production cost. Provided is an optical layered body having a hard coat layer formed on one surface of a light-transmitting substrate, wherein the hard coat layer has a surface roughness on its surface and the surface roughness satisfies the following inequalities of θa and Kr where θa is an average inclination angle of the uneven part and Kr is Kurtosis of the unevenness:0.01°≦θa≧0.10°1≦Kr≦3.

In image display devices such as a cathode-ray tube display device (CRT), a liquid crystal display (LCD), a plasma display (PDP), an electroluminescence display (ELD), and a field emission display (FED), an optical layered body composed of functional layers having various performances such as a reflection prevention performance, an antistatic performance, a hard coating property, and a stain prevention property is formed.
Such an optical layered body is obtained by layering various functional layers on a light-transmitting substrate. Accordingly, in the case where a hard coat, for example, is formed on a light-transmitting substrate, uneven patterns called interference fringes appear due to the interference of the reflected light on the interface of the light-transmitting substrate and the hard coat layer and the reflected light on the hard coat surface and unevenness of the coating thickness to result in a problem that the appearance is deteriorated.
In order to prevent generation of the interference fringes, for example, in the case where a hard coat layer is formed on a light-transmitting substrate, it has been know to use a solvent which can penetrate the light-transmitting substrate to swell or dissolve the substrate for a resin composition for forming the hard coat layer (e.g., see Patent Literatures 1 and 2). Use of a resin composition containing such a solvent forms an impregnated layer by impregnating the light-transmitting substrate with the resin in the resin composition owing to the penetration of the solvent to the light-transmitting substrate, and as a result, the interface between the light-transmitting substrate and the hard coat layer can substantially be eliminated to prevent generation of the interference fringes.
However, in the case of a conventional optical layered body in which interference fringes are prevented by forming such an impregnated layer, it is required to make the impregnated layer thick for sufficiently preventing generation of interference fringes, and thus it is inevitably needed to increase the application amount of a composition to be used at the time of forming a hard coat layer.
Accordingly, it results in a problem that an optical layered body may become difficult to be made thin and may be curled, and if the application amount of the composition at the time of forming a hard coat layer formation is large, it also results in a problem that the thickness of the hard coat layer to be formed becomes uneven and the production cost becomes high.
As an optical layered body to be used for the surface of an image display device, an optical layered body (an antiglare film) is also known which is provided with an antiglare property by forming an antiglare layer having, on its surface, an uneven form on a light-transmitting substrate. However, although preventing generation of interference fringes, the antiglare film causes a problem of giving white muddiness and lowering the contrast.

Optical layered body, polarizer and image display device


The folding work bench folds compactly for storage when not in use and occupies a minimal work space. The folding work bench has a durable work surface, a top storage shelf, a back board for hanging tools, a locking mechanism, and a work table that can be folded up against the back board and locked in a compactly folded configuration that also secures the tools on the back board in the work bench.

1. Field of the Invention
This invention relates to work benches, and more particularly relates to a folding work bench movable between a folded configuration or partially folded configuration for convenient space-saving storage, and an unfolded configuration to provide a working surface and work space with ready access to a user's tools.
2. General Background and State of the Art
Many home owners have limited work shop or garage space for home repair projects and home construction projects. Typical home work shop work benches are permanent structures occupying a constant amount of space whether in use or not, and having places for storage of tools for ready access for use at the work bench. In such crowded work shop or garage spaces, it would be desirable to store the work bench and tools in a smaller space when not in use. Hooks of various sorts are often provided for hanging tools for ready access, but such tools are also typically not securable against theft when the work bench area is not in use, and it would be desirable to provide a way of securing such a work bench collection of tools against theft when the work bench area is not in use. The present invention satisfies these and other needs.