XE1203 ETC1 [List of Unclassifed Manufacturers], XE1203 Datasheet - Page 9

• Manufacturer Part Number: XE1203
• Description: Low-Power, integrated UHF transceiver
• Manufacturer: ETC1 [List of Unclassifed Manufacturers]

4.1.3
The demodulation part is composed of an FSK demodulator, a bit synchronizer, a barker decoder and a Pattern
Recognition block. The next figure shows the interaction between each block.
4.1.4
The demodulator provides a bit stream from the received FSK modulated base band limited signals, I_lim and
Q_lim. If RTParam_bsync and RTParam_Barker bits are set low, i.e disabled, then the demodulator output is
directly connected to the DATA pin and the DCLK pin is set to low.
The modulation index required for proper operation of the demodulator is:
where f corresponds to the frequency deviation and BR corresponds to the bit rate.
9
2
BR
Demodulation chain
Demodulator
DEMODULATOR
f
, 2
FSK
FSParam_BR
RTParam_Barker
RTParam_Bitsync
pow
pow
SYNCHRONIZER
DECODER
BARKER
Figure 1 Demodulation architecture.
BIT
data
dclk
data
RTParam_Pattern
dclk
data
ADParam_Psize
ADParam_Pattern
ADParam_Ptol
pow
RECOGNIZER
PATTERN
CONTROL
DATA
Data Sheet
XE1203
pattern
data
dclk
D0308-214