This paper extends the work on cross-layer design which combines adaptive modulation and coding at the physical layer and hybrid automatic repeat request protocol at the data link layer. By contrast with previous work...This paper extends the work on cross-layer design which combines adaptive modulation and coding at the physical layer and hybrid automatic repeat request protocol at the data link layer. By contrast with previous works on this topic, the present development and the performance analysis as well, is based on rate compatible punctured turbo codes. Rate compatibility provides incremental redundancy in transmission of parity bits for error correction at the data link layer. Turbo coding and iterative decoding gives lower packet error rate values in low signal-to-noise ratio regions of the adaptive modulation and coding (AMC) schemes. Thus, the applied cross-layer design results in AMC schemes can achieve better spectral efficiency than convolutional one while it retains the QoS requirements at the application layer. Numerical results in terms of spectral efficiency for both turbo and convolutional rate compatible punctured codes are presented. For a more comprehensive presentation, the performance of rate compatible LDPC is contrasted with turbo case as well as the performance complexity is discussed for each of the above codes.展开更多
The purpose of this work is to associate the channel encoder called ‘trellis-coded modulation with Ungerboeck-Gray mapping’ (TCM-UGM) to ‘space–time block code’ (STBC), in order to study its performance to correc...The purpose of this work is to associate the channel encoder called ‘trellis-coded modulation with Ungerboeck-Gray mapping’ (TCM-UGM) to ‘space–time block code’ (STBC), in order to study its performance to correct the transmission errors of a JPEG image. The performance of the proposed scheme is evaluated in senses of bit error rate (BER), frame error rate (FER) and peak signal-to-noise ratio (PSNR) of the reconstructed image. Compared to the association TCM/STBC for a throughput of 2 bits/s/Hz, TCM-UGM/STBC permits to obtain a PSNR gain up to 2 dB.展开更多
文摘This paper extends the work on cross-layer design which combines adaptive modulation and coding at the physical layer and hybrid automatic repeat request protocol at the data link layer. By contrast with previous works on this topic, the present development and the performance analysis as well, is based on rate compatible punctured turbo codes. Rate compatibility provides incremental redundancy in transmission of parity bits for error correction at the data link layer. Turbo coding and iterative decoding gives lower packet error rate values in low signal-to-noise ratio regions of the adaptive modulation and coding (AMC) schemes. Thus, the applied cross-layer design results in AMC schemes can achieve better spectral efficiency than convolutional one while it retains the QoS requirements at the application layer. Numerical results in terms of spectral efficiency for both turbo and convolutional rate compatible punctured codes are presented. For a more comprehensive presentation, the performance of rate compatible LDPC is contrasted with turbo case as well as the performance complexity is discussed for each of the above codes.
文摘The purpose of this work is to associate the channel encoder called ‘trellis-coded modulation with Ungerboeck-Gray mapping’ (TCM-UGM) to ‘space–time block code’ (STBC), in order to study its performance to correct the transmission errors of a JPEG image. The performance of the proposed scheme is evaluated in senses of bit error rate (BER), frame error rate (FER) and peak signal-to-noise ratio (PSNR) of the reconstructed image. Compared to the association TCM/STBC for a throughput of 2 bits/s/Hz, TCM-UGM/STBC permits to obtain a PSNR gain up to 2 dB.
