GC5018_06 Datasheet, PDF (12/134 Pages) Texas Instruments – 8-CHANNEL WIDEBAND RECEIVER

GC5018
8-CHANNEL WIDEBAND RECEIVER
SLWS169A – MAY 2005 – REVISED NOVEMBER 2005
rxin_a
16
sync
Test and
16
Noise
Generator
16
data to FIFO for rxin_a
rxin_b
16
Test and
16
Noise
Generator
16
data to FIFO for rxin_b
rxin_c
rxin_d
rduz_sens_ena
slf_tst_ena
16
16
Test and
Noise
Generator
16
16
Test and
Noise
Generator
16
data to FIFO for rxin_c
16 _{data to FIFO for rxin_d}
Figure 3-9. Block diagram of Noise Generator Input Options
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The LFSR circuits can also be used to add noise to the rxin_a/b/c/d input signals by setting the
rduz_sens_ena control register bit. The magnitude of the noise added can be adjusted by programming
the nz_pwr_mask(15:0) control register. In the figure below, X = {a,b,c or d}.
rxin _X(15:0)
lfsr (15:0)
nz_pwr_mask(15:0)
16
16
16
16
to FIFO for rxin _X
16
16 XORs
16 ANDs
lfsr (17)
lfsr (16)
rduz_sens_ena
Figure 3-10. Detail Circuit for Adding Noise Generator Signal to rxin Signal
12
RECEIVE DIGITAL SIGNAL PROCESSING