A density evolution procedure for low-density parity-check (LDPC) codes under max-log-map decoding is presented. Using this technique. the precise convergence threshold for LDPC code could be easily derived.
A density evolution procedure for low-density parity-check (LDPC) codes under max-log-map decoding is presented. Using this technique. the precise convergence threshold for LDPC code could be easily derived.
In this correspondence, an analytical technique for bit-error probability of 2-state convolutional code with max-log-maximum a posteriori probability (map) decoding is presented. This technique employs an iterative ca...
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In this correspondence, an analytical technique for bit-error probability of 2-state convolutional code with max-log-maximum a posteriori probability (map) decoding is presented. This technique employs an iterative calculation of the probability density function (pdf) of the state metric per one transition, and gives the exact the bit-error probability for the overall signal-to-noise ratio (SNR).
In this letter, a theoretical analysis of bit error probability for 4-state convolutional code with max-log-maximum a posteriori probability (map) decoding is presented. This technique employs ail iterative calculatio...
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In this letter, a theoretical analysis of bit error probability for 4-state convolutional code with max-log-maximum a posteriori probability (map) decoding is presented. This technique employs ail iterative calculation of probability density function of the state metric per one transition, and gives the exact bit error probability for all signal-to-noise power ratio.
Turbo codes are preferred for high rate data services in the third generation mobile communication system *** low decoding delay and low complexity iterative decoding is of paramount importance. The modified soft outp...
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ISBN:
(纸本)0780363949
Turbo codes are preferred for high rate data services in the third generation mobile communication system *** low decoding delay and low complexity iterative decoding is of paramount importance. The modified soft output Viterbi algorithm(SOVA) and the max-log-maximum a posteriori(map) algorithm are such decoding *** equivalence of modified SOVA and max-log-map decodings has been proven on the assumption of no a priori information and infinite decoding *** the a priori information has to be updated continuously in iterative decoding,we prove their equivalence when there exits a priori information in this *** further demonstrate the equivalence between the sliding window(SW) max-log-map algorithm and the modified SOVA for finite decoding depth.
Existing schemes for blind recognition of channel codes make use of the average log-likelihood ratio (LLR) of each code's parity checks. There are difficulties in setting necessary thresholds and in theoretical an...
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Existing schemes for blind recognition of channel codes make use of the average log-likelihood ratio (LLR) of each code's parity checks. There are difficulties in setting necessary thresholds and in theoretical analysis of the method. This letter proposes to use the average likelihood difference (LD) of the parity checks. The computational complexity is reduced while the recognition performance is kept comparable to that of the LLR method. Moreover, an optimum decoding-based blind recognition is also described. Simulations show that, for rate 1/2 convolutional codes, this new method notably improves the performance.
Given a turbo code generated by parallelly concatenated recursive systematic convolutional encoders, the turbo decoder comprises map decoders coupled in a serial connection, where each map decoder decodes a recursive ...
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ISBN:
(纸本)9783030008253;9783030008246
Given a turbo code generated by parallelly concatenated recursive systematic convolutional encoders, the turbo decoder comprises map decoders coupled in a serial connection, where each map decoder decodes a recursive systematic convolutional code. We propose a turbo decoding algorithm that, on a logical level of abstraction, is made of several turbo decoders working in parallel. Each turbo decoder is initialized with different recursive convolutional code. Practical implementation of the proposed algorithm may be achieved with a single turbo decoder, where map decoders are working concurrently.
The log-domain BCJR algorithm is broadly used in iterative decoding processes. However, the serial nature of the recursive state metric calculations is a limiting factor for throughput increase. A possible solution re...
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ISBN:
(纸本)9781665409438
The log-domain BCJR algorithm is broadly used in iterative decoding processes. However, the serial nature of the recursive state metric calculations is a limiting factor for throughput increase. A possible solution resorts to high-radix decoding, which involves decoding several successive symbols at once. Despite several studies aiming at reducing its complexity, high-radix processing remains the most computationally intensive part of the decoder when targeting very high throughput. In this work, we propose a reformulation specifically targeting the complexity reduction of the recursive calculation units by either limiting the required number of operations or by selectively removing unnecessary ones. We report a complexity reduction of the add-compare-select units in the order of 50% compared to the recently proposed local-SOYA algorithm. In addition, our results show that several performance/complexity trade-offs can be achieved thanks to the proposed simplified variants. This represents a promising step forward in order to implement efficient very high throughput convolutional decoders.
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