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This paper proposes an efficient rateless low-density parity check (LDPC) codes for satellite broadcasting system. The proposed scheme uses the conventional LDPC codes specified in recent digital video broadcasting via satellite (DVB-S) standards, and concatenate them with Luby transform (LT)-like codes in order to form systematic rateless codes. In this way, redundant parities can be made at the...
The newly developed second generations standards for digital video broadcasting (DVB-T2, DVB-S2) emerges as a significant upgrade over its first generation predecessor. Low-Density Parity-Check (LDPC) codes received a lot of attention by their superb error-correcting capability and have been adopted as main error correct coding scheme by second generation Digital Video Broadcasting standards. The...
This paper analyzes the BER performance of Turbo code which is adapted for DVB-RCS2 standard with various modulation schemes. Firstly this paper introduces the turbo codes and demapping algorithm and analyzes the effect of noise valiance on the turbo decoder and simulates the effect of the performance of the turbo decoder according to the noise variance by adding a pseudo noise. From the result of...
In this paper, we apply an efficient scaling strategy on layered scaled min-sum LDPC decoder. In addition, we propose a joint optimization strategy for the quantization and scaling parameters of layered scaled min-sum LDPC decoder. The study of our optimization results, for DVB-S2 LDPC codes with different constellation sizes and code rates, shows that each constellation size code rate pair has different...
In this paper, a simplified partially parallel decoder architectural based on field programmable gate array (FPGA) devices for Digital Video Broadcasting-Satellite 2 low-density parity-check(DVB-S2-LDPC) codes has been presented. We introduce the current research status about decoder design for LDPC code and described the motivation of this paper in the first part. Then, we present the simulating...
The DVB-S2 standard has been revealed a reliable standard for data transmission thanks to the LDPC codes. The waterfall of the bit-error rate is very abrupt to reach low values of order 10^(-10) in the error floor. In this paper, we propose a novel investigation on the iterative decoding of these codes by the Belief Propagation algorithm on Gaussian channels. Introducing definitions of persistent...
In this paper, we propose a novel low complexity scaling strategy of min-sum decoding algorithm for irregular LDPC codes. In the proposed method, we generalize our previously proposed simplified Variable Scaled Min-Sum (SVS-min-sum) by replacing the sub-optimal starting value and heuristic update for the scaling factor sequence by optimized values. Density evolution and Nelder-Mead optimization are...
Digital video broadcasting-next generation handheld (DVB-NGH) is the first broadcasting standard that incorporates multiple-input multiple-output (MIMO) techniques to overcome the Shannon limit of single antenna systems. This paper contributes to analyze the performance of the DVB-NGH MIMO coded modulation system. The detailed performance degradation from information-theoretic limit to implementation...
The combination of low-density parity-check (LDPC) codes and bit-interleaved coded modulation (BICM) scheme, could easily break the bound of the cut-off rate and achieve capacity-approaching performance. To overcome the independent demapping loss in BICM scheme, the iterative demapping counterpart of BICM (BICM-ID) was further proposed. In this paper, we will present a viewpoint that the performance...
This paper proposes an adaptive normalized min-sum algorithm for the decoding of low-density parity check (LDPC) codes, which utilizes an adaptive normalization factor to improve the accuracy of the soft information transferred during the iterative decoding process, and provides superior performance accordingly. This adaptive normalization factor can be adjusted dynamically and adaptively at each...
Current DVB-SH systems rely on hierarchical modulation to insert local content into the complementary ground component. The local content is inserted as a low priority bit stream, while the global content will be transmitted as a high-priority bit stream. At the receiver, the standard approach of extracting the local content from the received signal first requires detection of the global content....
Because of its proximity to Shannon limit error-correcting ability, Turbo codes have attracted great attentions. Its excellent error correction performance has become an important research in the field of channel coding. We introduce Turbo codes into the error correction mechanism of the DVB-T system, and then use MATLAB to simulate the improved correction mechanism. Simulation results show that the...
The paper proposes an approach to scale-down the LDPC code length, thus saving memory and processing power, without significantly sacrificing the code robustness. the paper describes how to use specific Low Density Parity Check (LDPC) codes for Digital Video Broadcasting Terrestrial Second Generation DVB-T2. While the original LDPC codes are rather long 16200 bits and 64800 bits, we propose to reduce...
DVB-SH systems rely on hierarchical modulation to insert local content in the complementary ground component. The local content is inserted as a low priority (LP) bit stream, while the global content will be transmitted as a high-priority (HP) bit stream. At the receiver, the standard approach of extracting the local content from the received signal requires to detect the global content first. Henceforth,...
Because it is widely supported by commercial-off-the-shelf (COTS) technology, the DVB-S2 waveform standard has become an attractive solution for military communication links. The waveform uses a combination of amplitude-phase-shift keying (APSK) modulation and low-density parity-check (LDPC) codes. Typical DVB-S2 implementations select signals from the APSK signal set with uniform probability. However,...
Most high-throughput, fixed-point processors offer at least two options for arithmetic operations: 8-bit arithmetic, and 16-bit arithmetic. The lower resolution provides higher computational throughput at the cost of poorer performance in many applications. We investigate the effect of the resolution of saturating, fixed-point arithmetic on the performance of the turbo-decoding message-passing algorithm...
Rotated QAM constellations improve Bit-Interleaved Coded Modulation (BICM) performance over fading channels. Indeed, an increased diversity is obtained by coupling a constellation rotation with interleaving between the real and imaginary components of transmitted symbols either in time or frequency domain. Iterative processing at the receiver side can provide additional improvement in performance...
In this paper, we propose a scheme for increasing the capacity of a communication channel by overloading a pre-existing channel with a controlled interfering channel using Raptor code. Combination of Raptor code and use of interference cancellation in the resulting Multiple Access Channel (MAC) results in almost perfect removal of the effect of the interfering channel. Thus, the primary channel's...
Bit-Interleaved Coded Modulation (BICM) offers a significant improvement in error correcting performance for coded modulations over fading channels compared to the previously existing techniques. Iterative processing at the receiver side can provide additional improvement to the BICM performance. In this paper, an efficient shuffled iterative receiver is investigated for the second generation of the...
This paper deals with simulation of transmission in the DVB-SH-A (Digital Video Broadcasting — Satellite Services to Handhelds, OFDM mode) standard in Gaussian (AWGN) and mobile fading channels (RA6, TU6). An application for such simulation was developed in MATLAB. Turbo encoder, which is used in DVB-SH (3GPP2), was modified for the simulation. The modified turbo encoder and the selected turbo decoding...
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