Agilent Technologies ESA-E Series Measurement Manual page 9

Bluetooth™ Use Model
Bluetooth™ System Overview
A Bluetooth™ channel is divided into timeslots, each 625 µs in length. In the
Time-Division Duplex (TDD) scheme used, the master transmits in
even-numbered timeslots, and the slave in odd-numbered timeslots. Voice or data
communication within piconets is transmitted in packets. Data packets may extend
over one, three, or five time slots, whereas voice packets are limited to a single
time slot. An RF hop occurs at the end of the last time slot associated with the
packet.
A packet, shown in Figure 1-2, contains an access code, header and payload. The
access code consists of a preamble, a sync word, and an optional trailer. The
header contains piconet member address and packet information. The payload
data, consisting of payload header, payload data and CRC, carries the user's voice
or data information. The payload CRC (Cyclic Redundancy Check) is a 16-bit
field at the end of the payload that is used for a data integrity check. Depending on
the packet type, a payload starts with a 1 (DH1) or 2 (DH3/5) byte header, and
finishes with a 2 byte CRC.
Figure 1-2 Bluetooth™ General Packet Format
The link manager needs to support the Bluetooth™ test modes. These test modes
should provide key capabilities for testing Bluetooth™ devices. These capabilities
include the ability to place the device into test loopback mode and the ability to
define transmit and receive frequencies, power control, and other key parameters.
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