| 1. |
- Mitchell, David G.M., et al.
(författare)
-
Approximating Decoding Thresholds of Punctured LDPC Code Ensembles on the AWGN Channel
- 2015
-
Ingår i: 2015 IEEE International Symposium on Information Theory (ISIT). - 9781467377041 ; , s. 421-425
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we provide an efficient way to predict iterative belief propagation (BP) decoding thresholds of randomly punctured low-density parity-check (LDPC) code ensembles on the binary-input additive white Gaussian noise channel (AWGNC), given only the BP threshold of the mother code ensemble on the binary erasure channel (BEC) and the code design rate. We show that the predictions are accurate by comparing them with values calculated by discretized density evolution for a variety of puncturing fractions. We find that the strength and suitability of an LDPC code ensemble for random puncturing over the AWGNC with respect to iterative decoding threshold is completely determined by a single constant, and this behavior is demonstrated using both LDPC block code and spatially coupled LDPC code ensembles. Finally, we present simulation results that confirm the excellent decoding performance promised by the asymptotic results.
|
|
| 2. |
- Mitchell, David G. M., et al.
(författare)
-
On the Block Error Rate Performance of Spatially Coupled LDPC Codes for Streaming Applications
- 2016
-
Ingår i: Proc. IEEE Information Theory Workshop. - 9781509010905
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we study the block error rate (BLER) performance of spatially coupled low-density parity-check (SC- LDPC) codes using a sliding window decoder suited for streaming applications. Previous studies of SC-LDPC have focused on the bit error rate (BER) performance or the frame error rate (FER) performance over the entire length of the code. Here, we consider protograph-based constructions of SC-LDPC codes in which a window decoder continuously outputs blocks in a streaming fashion, and we examine the BLER associated with these blocks.We begin by examining the effect of protograph design on the streaming BLER by varying the block size and the coupling width in such a way that the overall constraint length of the SC-LDPC code remains constant. Next, we investigate the BLER scaling behavior with block size and coupling width. Lastly, we consider the effect of employing an outer code to protect blocks, so that small numbers of residual errors can be corrected by the outer code. Simulation results for the additive white Gaussian noise channel (AWGNC) are included and comparisons are made to LDPC block codes (LDPC-BCs).
|
|
| 3. |
- Mitchell, David G.M., et al.
(författare)
-
Randomly Punctured LDPC Codes
- 2016
-
Ingår i: IEEE Journal on Selected Areas in Communications. - 1558-0008. ; 34:2, s. 408-421
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present a random puncturing analysis of low-density parity-check (LDPC) code ensembles. We derive a simple analytic expression for the iterative belief propagation (BP) decoding threshold of a randomly punctured LDPC code ensemble on the binary erasure channel (BEC) and show that, with respect to the BP threshold, the strength and suitability of an LDPC code ensemble for random puncturing is completely determined by a single constant that depends only on the rate and the BP threshold of the mother code ensemble. We then provide an efficient way to accurately predict BP thresholds of randomly punctured LDPC code ensembles on the binary- input additive white Gaussian noise channel (BI-AWGNC), given only the BP threshold of the mother code ensemble on the BEC and the design rate, and we show how the prediction can be improved with knowledge of the BI-AWGNC threshold. We also perform an asymptotic minimum distance analysis of randomly punctured code ensembles and present simulation results that confirm the robust decoding performance promised by the asymptotic results. Protograph-based LDPC block code and spatially coupled LDPC code ensembles are used throughout as examples to demonstrate the results.
|
|
| 4. |
- Mitchell, David G.M., et al.
(författare)
-
Randomly Punctured Spatially Coupled LDPC Codes
- 2014
-
Ingår i: [Host publication title missing].
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we study random puncturing of protograph-based spatially coupled low-density parity-check (SC- LDPC) code ensembles. We show that, with respect to iterative decoding threshold, the strength and suitability of an LDPC code ensemble for random puncturing over the binary erasure channel (BEC) is completely determined by a single constant that depends only on the rate and iterative decoding threshold of the mother code ensemble. We then use this analysis to show that randomly punctured SC-LDPC code ensembles display near capacity thresholds for a wide range of rates. We also perform an asymptotic minimum distance analysis and show that, like the SC-LDPC mother code ensemble, the punctured SC-LDPC code ensembles are also asymptotically good. Finally, we present some simulation results that confirm the excellent decoding performance promised by the asymptotic results.
|
|
| 5. |
- Pusane, Ali Emre, et al.
(författare)
-
Multi-level coding/modulation using LDPC convolutional codes
- 2004
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we propose a novel multilevel coding scheme that employs low-density parity-check convolutional (LDPCC) codes. A combined decoding/ demodulation scheme is also considered. Unlike previous work on multilevel coding, the proposed scheme employs a single code with some structure that allows it to benet from the use of multilevel mapping. The proposed scheme can be seen as a form of bit-interleaved coded-modulation (BICM) that employs multilevel mapping and iterative demodulation and a code with structure.
|
|
| 6. |
- Ul Hassan, Najeeb, et al.
(författare)
-
Non-Uniform Window Decoding Schedules for Spatially Coupled LDPC Codes
- 2017
-
Ingår i: IEEE Transactions on Communications. - 0090-6778. ; 65:2, s. 501-510
-
Tidskriftsartikel (refereegranskat)abstract
- Spatially coupled low-density parity-check codes can be decoded using a graph-based message passing algorithm applied across the total length of the coupled graph. However, considering practical constraints on decoding latency and complexity, a sliding window decoding approach is normally preferred. In order to reduce decoding complexity compared with standard parallel decoding schedules, serial schedules can be applied within a decoding window. However, uniform serial schedules within a window do not provide the expected reduction in complexity. Hence, we propose non-uniform schedules (parallel and serial) based on measured improvements in the estimated bit error rate (BER). We show that these non-uniform schedules result in a significant reduction in complexity without any loss in performance. Furthermore, based on observations made using density evolution, we propose a non-uniform pragmatic decoding schedule (parallel and serial) that does not require any additional calculations (e.g., BER estimates) within the decoding process.
|
|
| 7. |
- Zhang, Wei, et al.
(författare)
-
Braided convolutional codes
- 2005
-
Ingår i: [Host publication title missing]. - 0780391519 ; , s. 592-596
-
Konferensbidrag (refereegranskat)abstract
- We present a new class of iteratively decodable turbo-like codes, called braided convolutional codes. Constructions and encoding procedures for tightly and sparsely braided codes are introduced. Sparsely braided codes exhibit good convergence behavior with iterative decoding, and a statistical analysis using Markov permutors shows that the free distance of these codes grows linearly with constraint length
|
|
