BC41B143A-DS-002PD Datasheet, PDF (47/89 Pages) List of Unclassifed Manufacturers – BlueCore 4-ROM CSP EDR Single Chip Bluetooth v2.0 + EDR System

Enhanced Data Rate
01
00
11
10
Figure 10.2: π/4 DQPSK Constellation Pattern
Bit Pattern
Phase Shift
00
π/4
01
3π/4
11
-3π/4
10
-π/4
Table 10.2: 2-Bits Determine Phase Shift Between Consecutive Symbols
10.3 Enhanced Data Rate 8DPSK
3x data rate modulation uses eight phase differential phase shift keying (8DPSK). Each symbol in the payload
portion of the packet represents three baseband bits. Although 8DPSK appears to be similar to π/4 DQPSK, the
differential phase shifts between symbols are now permissible between any of the eight possible phase states.
This reduces the separation between adjacent symbols on the constellation to π/4 (45°C) and thereby reduces
the noise and interference immunity of the modulation scheme. Nevertheless, since each symbol now represents
3 baseband bits, the actual throughput of the data is 3x when compared with the basic data rate packet.
Figure 10.3 illustrates the 8DPSK constellation and Table 10.3 defines the phase encoding.
BC41B143A-ds-002Pd
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