arXiv subjects

Rolando Carrasco

Publications and source records attributed to Rolando Carrasco.

4 recordsLinked to original sources

arXiv2017

Design of Polar Codes with Single and Multi-Carrier Modulation on Impulsive Noise Channels using Density Evolution

In this paper, density evolution-based construction methods to design good polar codes on impulsive noise channels for single-carrier and multi-carrier systems are proposed and evaluated. For a single-carrier system, the tight bound of the block error probability (BLEP) is derived by applying density evolution and the performance of the proposed construction methods are compared. For the multi-carrier system employing orthogonal frequency-division multiplexing, the accurate BLEP estimation is not feasible so a tight lower bound on the BLEP for polar codes is derived by assuming the noise on each sub-carrier is Gaussian. The results show that the lower bound becomes tighter as the number of carriers increases.

cs.IT↗

arXiv2008

On the Frame Error Rate of Transmission Schemes on Quasi-Static Fading Channels

It is known that the frame error rate of turbo codes on quasi-static fading channels can be accurately approximated using the convergence threshold of the corresponding iterative decoder. This paper considers quasi-static fading channels and demonstrates that non-iterative schemes can also be characterized by a similar threshold based on which their frame error rate can be readily estimated. In particular, we show that this threshold is a function of the probability of successful frame detection in additive white Gaussian noise, normalized by the squared instantaneous signal-to-noise ratio. We apply our approach to uncoded binary phase shift keying, convolutional coding and turbo coding and demonstrate that the approximated frame error rate is within 0.4 dB of the simulation results. Finally, we introduce performance evaluation plots to explore the impact of the frame size on the performance of the schemes under investigation.

cs.IT↗

arXiv2007

Pseudo-random Puncturing: A Technique to Lower the Error Floor of Turbo Codes

It has been observed that particular rate-1/2 partially systematic parallel concatenated convolutional codes (PCCCs) can achieve a lower error floor than that of their rate-1/3 parent codes. Nevertheless, good puncturing patterns can only be identified by means of an exhaustive search, whilst convergence towards low bit error probabilities can be problematic when the systematic output of a rate-1/2 partially systematic PCCC is heavily punctured. In this paper, we present and study a family of rate-1/2 partially systematic PCCCs, which we call pseudo-randomly punctured codes. We evaluate their bit error rate performance and we show that they always yield a lower error floor than that of their rate-1/3 parent codes. Furthermore, we compare analytic results to simulations and we demonstrate that their performance converges towards the error floor region, owning to the moderate puncturing of their systematic output. Consequently, we propose pseudo-random puncturing as a means of improving the bandwidth efficiency of a PCCC and simultaneously lowering its error floor.

cs.IT↗

arXiv2007

A Union Bound Approximation for Rapid Performance Evaluation of Punctured Turbo Codes

In this paper, we present a simple technique to approximate the performance union bound of a punctured turbo code. The bound approximation exploits only those terms of the transfer function that have a major impact on the overall performance. We revisit the structure of the constituent convolutional encoder and we develop a rapid method to calculate the most significant terms of the transfer function of a turbo encoder. We demonstrate that, for a large interleaver size, this approximation is very accurate. Furthermore, we apply our proposed method to a family of punctured turbo codes, which we call pseudo-randomly punctured codes. We conclude by emphasizing the benefits of our approach compared to those employed previously. We also highlight the advantages of pseudo-random puncturing over other puncturing schemes.

cs.IT↗