
STV0196B
QPSK/BPSK DEMODULATOR AND FEC IC
I AND Q 6 BITSDIGITAL INPUTS AT 2Fs
.
QPSKDEMODULATION (TwoModes : Aand B)
.
INPUT SYMBOL FREQUENCY (Fs)
30MSYMBOLS/S
.
DIGITALNYQUIST ROOT FILTER :
ROLL-OFF VALUEOF 0.35 IN MODE A
.
DIGITALCARRIER LOOP:
- ON-CHIP DEROTATOR AND TRACKING
LOOP
- CARRIER OFFSETINDICATOR
- LOCKDETECTOR
- C/N INDICATOR FOR DISH POSITIONING
.
DIGITALTIMING RECOVERY :
- INTERNAL TIMING ERROR EVALUATION
AND FILTER
- OUTPUT CONTROL
SIGNAL FOR A 2Fs
EXTERNAL VCO OR VCXO
.
DIGITALAGC:
- INTERNAL SIGNAL POWER ESTIMATION
AND FILTER
- OUTPUT CONTROL SIGNAL FOR AGC
(1 BIT PULSE DENSITY MODULATION)
FORWARD ERROR CORRECTION
.
INNER DECODER :
- VITERBISOFT DECODER FOR CONVOLU-
TIONAL CODES, CONSTRAINT LENGTH
M = 7, RATE 1/2
- PUNCTURED CODES 1/2, 2/3, 3/4, 5/6 AND
7/8 IN MODE A
- AUTOMATIC OR MANUAL RATE AND
PHASERECOGNITION
.
DEINTERLEAVER :
- WORDSYNCHRO EXTRACTION
- CONVOLUTIVE DEINTERLEAVER
.
OUTER DECODER :
- IN MODE A : REED-SOLOMON DECODER
FOR 16 PARITY BYTES; CORRECTION OF
UP TO 8 BYTEERRORS
- BLOCKLENGTHS : 204 IN MODE A
- ENERGYDISPERSAL DESCRAMBLER
CONTROL
.
I
2
C SERIALBUS
September 1996
PQFP64
(Plastic Package)
ORDER CODE :
STV0196B
FRONT-END INTERFACE
UP TO
DESCRIPTION
Designed for the fast growing direct broadcast
satellite
(DBS) digital TV receiver market,
the SGS-THOMSON STV0196B Digital Satellite
Receiver Front-end integrates all the functions
neededto demodulateincomingdigital satellite TV
signalsfromthetuner:Nyquistfilters,QPSK/BPSK
demodulator, signal power estimator, automatic
gain control, Viterbi decoder, deinterleaver,Reed-
Solomon decoder and energy dispersal descram-
bler. This high level of integrationgreatly reduces
the package count and cost of a set top box. The
demodulator blocks are suitable for a wide range
of symbolrateswhiletheadvancederror correction
functionsguaranteealowerrorrateevenwithsmall
receiver antennas or low powertransmitters.
The STV0196Bhas multistandard capability.
It is fully compliant with the recentlydefinedDigital
Video Broadcasting (DVB) standard (already
adopted by satellite TV operators in the USA,
Europe and Asia) and also compatible with the
mainconsumerdigitalsatelliteTVstandardsinuse.
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