AUTHORS: Bashar M. Mansoor, Tariq Z. Ismaeel
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ABSTRACT: Due to their low delay and complexity, short length codes are attractive for use in wireless communication systems. Also, achieving low complexity, high performance and low decoding latencies, is the key requirements of low-density parity-check (LDPC) code because these provide more reliable code for many applications. In this paper, a novel method was proposed to construct a short length code based on the convolutional encoder and LDPC decoder. In this code, delay and computational complexity of encoding and decoding were significantly reduced compared to other LDPC codes when they were simulated at the same length and code rate. The main contribution of this work was to design a code with low time delay and low computation complexity while having an improved bit error rate (BER) performance. Complexity and latency were reduced by using a convolutional technique for the encoding and by providing an improved parity-check matrix for the decoding. The codes were simulated over additive white Gaussian noise (AWGN) channel using different modulation schemes. Theoretical analysis denoted that the encoder and decoder may offer advantages in terms of latency and complexity, while simulation results have showed that the proposed code achieved an improvement over other LDPC codes that have the same length and code rates.
KEYWORDS: LDPC codes, Low-density parity-check matrix (H), Convolutional encoder, Decoding complexity, Latency, BER performance.
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