The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. System Architecture Chapter 3 Packet-Dedicated Control Channel (PDCCH) Packet Associated Control Channel (PACCH) This is an uplink and downlink function used to carry signaling information to and from the mobile station. PACCH shares resources with the PDTCH assigned to the mobile station. Packet Timing Advance Control Channel/Uplink (PTCCH/UL) This is used for estimation of timing advance of one mobile station. Packet Timing Advance Control Channel/Downlink (PTCCH/DL) This is used to transmit timing advance information to several mobile stations. One PTCCH/DL is paired with several PTTCH/ULs. Mapping Logical Channels onto Physical Channels As stated earlier, logical channels are carried on physical channels. In fact, multiple logical channels can be mapped onto the same physical channel in a timesharing fashion using a superframe structure. Several combinations of logical channels can be multiplexed onto the same physical channel; these are shown in Figure 3-12. Three possible combinations are allowable: Broadcast Control + Common Control + Traffic + Dedicated Control PBCCH + PCCCH + PDTCH + PACCH + PTCCH Common Control + Traffic + Dedicated Control PCCCH + PPDTCH + PACCH + PTCCH Traffic + Dedicated Common Control PCTCH + PACCH + PTCCH Note that the Packet Common Control Channel (PCCCH) is made up of the following logical channels: PCCH = PAGCH + PPCH + PRACH + PNCH Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. System Architecture System Architecture Figure 3-12 Broadcast Physical Mapping the logical Common Control channels on the Channel Traffic & Dedicated Control physical channels. Common Control Physical Traffic & Dedicated Control Channel Physical Traffic & Dedicated Control Channel The combinations previously listed are no