This paper presents a concatenated coded modulationschemefor errorcontrolin datacommunications. The schemeis achievedby concatenating a Reed-Solomon.outer code and a bandwidth efficientblock inner code for M-ary PSK m...
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This paper presents a concatenated coded modulation
schemefor errorcontrolin datacommunications. The schemeis achieved
by concatenating a Reed-Solomon.outer code and a bandwidth efficient
block inner code for M-ary PSK modulation. Error performance of
the scheme is analyzed for an AWGN channel. We show that extremely
high reliability can be attained by using a simpleM-ary PSK modula-
tion inner code and a relatively powerful Reed-Solomon.outer code.
Furthermore, if an inner code of high effective rate is used, the band-
width expansion required by the scheme due to coding will be greatly
reduced. The proposed scheme is particularly effective for high-speed
satellite communications for large file transfer where high reliability is
required.
This paper also presents a simplemethod for constructingblock codes
for M-ary PSK modulation. Some shortM-ary PSK codes with good
minimum squared Euclidean distance are *** codes have
trellis structure and hence can be decoded with a soft-decision Viterbi
decoding algorithm. Furthermore, some of these codes are phase invari-
ant under multiples of 45’ rotation.
This paper presents a method for evaluating the bit-error probability of a concatenated coding system for BPSK transmission over the AWGN channel, In the concatenated system, a linear Binary block code is used as the ...
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This paper presents a method for evaluating the bit-error probability of a concatenated coding system for BPSK transmission over the AWGN channel, In the concatenated system, a linear Binary block code is used as the inner code and is decoded with the soft-decision maximum likelihood decoding, and a maximum distance separable code (or its interleaved code) is used as the.outer code and is decoded with a bounded distance decoding, The method is illustrated through a specific example in which the inner code is a binary (64,40,8) Reed-Muller subcode and the.outer code is the NASA standard (255,223,33) Reed-Solomon code over GF(2(8)) interleaved to a depth of 5, This specific concatenated system is being considered for NASA's high-speed satellite communications, The bit-error performance is evaluated by a combination of simulation and analysis, The split weight enumerators for the maximum distance separable codes are derived and used for the analysis.
High rate concatenated coding systems with bandwidthefficient trellis inner codes and Reed-Solomon (RS).outer codes areinvestigated for application in high-speed satellite communication sys-tems. Two concatenated codi...
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High rate concatenated coding systems with bandwidth
efficient trellis inner codes and Reed-Solomon (RS).outer codes are
investigated for application in high-speed satellite communication sys-
tems. Two concatenated coding schemes are proposed. In Scheme I, the
inner code is decoded with soft-decision Viterbi decoding and the outer
RS code performs error-correction only decoding (decoding without side
information). In Scheme 11, the inner code is decoded with a modified
Viterbi algorithm which produces reliability information along with the
decoded output. In this algorithm, path metrics are used to estimate the
entire information sequence, while branch metrics are used to provide
reliabilityinformationon the *** informationis used
to erase unreliable bits in the decoded output. An errors-anderasuresRS
decoder is then used for the.outer code. These two schemes have been
proposed for high-speed data communicationon NASA satellite chan-
nels. The ratesconsideredare at least double those used in current NASA
systems, and our results indicate that high system reliability can still be
achieved.
Iterative demodulation and decoding of convolutionally encoded data is treated as a special case of the recently proposed serial concatenation of interleaved codes. It is shown that by exploiting the recursive nature ...
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Iterative demodulation and decoding of convolutionally encoded data is treated as a special case of the recently proposed serial concatenation of interleaved codes. It is shown that by exploiting the recursive nature of the differential modulation schemes (for example, DBPSK, DQPSK, CPM, etc.), large interleaving gains tan be achieved similar to serial concatenation schemes. We also show that when memoryless modulation is used, preceding can be used to create a rate-1 recursive inner code in order to obtain interleaving gains without adding redundancy from the inner code.
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