se a handshaking protocol Class 3 No minimum to regulate data accumulation and the instantaneous rate specified is not usually critical. Thus, for ACL links the master has considerable leeway in proportioning data transfer with Receiver sensitivity -70 dBm for BER = 0.1% the slaves in its network. An ARQ (automatic repeat re- quest) protocol is always used, in addition to optional Short-range wireless applications and technologies CHAPTER 5.2 APPLICATION SOFTWARE BASEBAND GAUSSIAN LOW PASS FILTER MODULATOR ENCRYPTION; ERROR CORRECTION AND FREQ. CONTROL DETECTION; FREQUENCY SCRAMBLING; REFERENCE SYNTHESIZER PACKET FORMATION DOWNCONVERTER DETECTOR CONTROL FILTER Figure 5.2-17 Bluetooth transceiver. error correction, to ensure the highest reliability of the until it's time for the next master transmission. The data transfer. master also indicates the length of its transmission (one, Bluetooth was conceived for employment in mobile three, or five slots) in its message header, SO the slave can and portable devices, which are more likely than not extend its sleep time during a multiple slot interval. to be powered by batteries, SO power consumption is an important issue. In addition to achieving low-power Sniff mode consumption due to relatively low transmitting power In this mode, sleep time is increased because the slave levels, Bluetooth incorporates power saving features in its knows in advance the time interval between slots during communication protocol. Low average power is achieved which the master may address the slave. If it's not by reducing the transmission duty cycle, and putting the addressed during the agreed slot, it returns to its low- device in a low-power standby mode for as long a period power state for the same period and then wakes up and as possible relative to transmit and receive times while listens again. When it is addressed, the slave continues still maintaining the minimum data flow requirements. listening during subsequent master transmission slots as Bluetooth has three modes for achievin