scholarly journals Improving the performance of BICM-ID and MLC systems with different FEC codes

2013 ◽  
Vol 11 ◽  
pp. 87-93 ◽  
Author(s):  
T. Arafa ◽  
W. Sauer-Greff ◽  
R. Urbansky
Keyword(s):  
Turbo Codes ◽  
Channel Coding ◽  
Communication Systems ◽  
Forward Error Correction ◽  
Convolutional Codes ◽  
Coded Modulation ◽  
Modulation Formats ◽  
Coding Schemes ◽  
Multilevel Modulation ◽  
Exit Charts

Abstract. In bandwidth limited communication systems, the high data rate transmission with performance close to capacity limits is achieved by applying multilevel modulation schemes in association with powerful forward error correction (FEC) coding, i.e. coded modulation systems. The most important practical approaches to coded modulation systems are multilevel coding with multistage decoding (MLC/MSD) and bit interleaved coded modulation with iterative demapping and decoding (BICM-ID). Multilevel modulation formats such as M-QAM, which can be used as a part of coded modulation systems, have the capability of multilevel protection. Based on this fact, we investigate the methods to improve the performance of BICM-ID using multiple interleavers with different binary channel coding schemes such as convolutional codes, turbo codes and low-density parity-check (LDPC) codes. Moreover, an MLC system with parallel decoding on levels (PDL) at the receiver is considered. In our contribution, we propose to design the individual coding schemes using the extrinsic information transfer (EXIT) charts for individual bit levels in the constellation. Our simulation results show that the BICM-ID systems, taking into account different bit-level protections, can provide an improvement of 0.65 dB, 1.2 dB and 1.5 dB for 256-QAM with turbo, LDPC and convolutional codes, respectively. On the other hand, MLC systems with PDL designed using EXIT charts for individual bit levels can slightly improve the performance and eliminate the error floor compared to the systems with MSD.

scholarly journals Hard-Decision Coded Modulation for High-Throughput Short-Reach Optical Interconnect

Entropy ◽  
2020 ◽  
Vol 22 (4) ◽  
pp. 400
Author(s):  
Bin Chen ◽  
Yi Lei ◽  
Gabriele Liga ◽  
Chigo Okonkwo ◽  
Alex Alvarado
Keyword(s):  
Communication Systems ◽  
Forward Error Correction ◽  
Additive White Gaussian Noise ◽  
Coded Modulation ◽  
Fiber System ◽  
Modulation Formats ◽  
High Data ◽  
Data Rates ◽  
Forward Error ◽  
Hard Decision

Coded modulation (CM), a combination of forward error correction (FEC) and high order modulation formats, has become a key part of modern optical communication systems. Designing CM schemes with strict complexity requirements for optical communications (e.g., data center interconnects) is still challenging mainly because of the expected low latency, low overhead, and the stringent high data rate requirements. In this paper, we propose a CM scheme with bit-wise hard-decision FEC and geometric shaping. In particular, we propose to combine the recently introduced soft-aided bit-marking decoding algorithm for staircase codes (SCCs) with geometrically-shaped constellations. The main goal of this CM scheme is to jointly boost the coding gain and provide shaping gain, while keeping the complexity low. When compared to existing CM systems based on M-ary quadrature-amplitude modulation (MQAM, M = 64 , 128 , 256 ) and conventional decoding of SCCs, the proposed scheme shows improvements of up to 0 . 83 dB at a bit-error rate of 10 - 6 in the additive white Gaussian noise channel. For a nonlinear optical fiber system, simulation results show up to 24 % reach increase. In addition, the proposed CM scheme enables rate adaptivity in single-wavelength systems, offering six different data rates between 450 Gbit/s and 666 Gbit/s.

Performance Analysis of Multiple FEC Channel Coding Algorithms for Software Defined Radio Using Quadrature Amplitude Modulation

2016 ◽  
Vol 7 (2) ◽  
pp. 1-15 ◽  
Author(s):  
Nikhil Marriwala ◽  
O. P. Sahu ◽  
Anil Vohra
Keyword(s):  
Amplitude Modulation ◽  
Turbo Codes ◽  
Channel Coding ◽  
Software Defined Radio ◽  
Communication Systems ◽  
Forward Error Correction ◽  
Additive White Gaussian Noise ◽  
Original Data ◽  
Quadrature Amplitude Modulation ◽  
Experimental Result

This paper describes the development of a Software Defined Radio (SDR)-based Transceiver simulation model using Quadrature Amplitude Modulation (QAM) Scheme and analyze its performance using Forward Error Correction (FEC) channel coding algorithms namely the Convolution and the Turbo Codes. This model efficiently evaluates the performance of high data rate multi array M-QAM, schemes. The performance of these FEC codes is evaluated when the system is subjected to noise and interference in the channel. In this design Additive White Gaussian Noise (AWGN) channel has been considered. The design is analyzed using Bit Error Rate (BER) and Signal to Noise Ratio (SNR) for different M-QAM techniques. The simulation results give a possible solution for future SDR systems which may be used in various wireless communication systems. An experimental result shows that the QAM transceiver achieves the transmission of data at high level accurately. FEC Channel coding scheme is used wherever the re-transmission of the data is not feasible. On the receiver side, this channel coded signal is decoded in order to get back the original data even if the channel coded signal undergoes some interference from the noise in the transmission medium. The Performance is then analyzed in terms of BER for Convolution Coding and Turbo Coding algorithm at a particular value of SNR in LabVIEW graphical programming. Finally, comparison has been drawn based on different parameters between the existing SDR system and the proposed design in this paper to analyze and highlight the effectiveness of the proposed SDR design.

scholarly journals An Asynchronous Low Power and High Performance VLSI Architecture for Viterbi Decoder Implemented with Quasi Delay Insensitive Templates

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
T. Kalavathi Devi ◽  
Sakthivel Palaniappan
Keyword(s):  
Low Power ◽  
Communication Systems ◽  
High Speed ◽  
High Performance ◽  
Large Scale ◽  
Forward Error Correction ◽  
Vlsi Architecture ◽  
Convolutional Codes ◽  
Viterbi Decoder ◽  
Asynchronous Design

Convolutional codes are comprehensively used as Forward Error Correction (FEC) codes in digital communication systems. For decoding of convolutional codes at the receiver end, Viterbi decoder is often used to have high priority. This decoder meets the demand of high speed and low power. At present, the design of a competent system in Very Large Scale Integration (VLSI) technology requires these VLSI parameters to be finely defined. The proposed asynchronous method focuses on reducing the power consumption of Viterbi decoder for various constraint lengths using asynchronous modules. The asynchronous designs are based on commonly used Quasi Delay Insensitive (QDI) templates, namely, Precharge Half Buffer (PCHB) and Weak Conditioned Half Buffer (WCHB). The functionality of the proposed asynchronous design is simulated and verified using Tanner Spice (TSPICE) in 0.25 µm, 65 nm, and 180 nm technologies of Taiwan Semiconductor Manufacture Company (TSMC). The simulation result illustrates that the asynchronous design techniques have 25.21% of power reduction compared to synchronous design and work at a speed of 475 MHz.

scholarly journals Secure image transmission over wireless network

2018 ◽  
Vol 7 (4) ◽  
pp. 2758
Author(s):  
Salah A. Aliesawi ◽  
Dena S. Alani ◽  
Abdullah M. Awad
Keyword(s):  
Turbo Codes ◽  
Channel Coding ◽  
Communication Systems ◽  
Wireless Channels ◽  
Image Transmission ◽  
Signal Propagation ◽  
Data Encryption ◽  
Error Rates ◽  
Delay Spread ◽  
High Level

The advances recently seen in data compression, and communication systems, have made it viable to design wireless image transmission systems. For many applications such as confidential transmission, military and medical applications, data encryption techniques should be also used to protect the confidential data from intruders. For these applications, both encryption and compression need to be performed to transmit a message in a fast and secure way. Further, the wireless channels have fluctuating channel qualities and high bit error rates. In this paper, a new scheme based on encryption and channel coding has been proposed for secure image transmission over wireless channels. In the proposed scheme, the encryption process is based on keys generator and Chaotic Henon map. Turbo codes are utilized as channel coding to deal effectively with the channel errors, multipath signal propagation and delay spread. Simulation results show that the proposed system achieves a high level of robustness against wide different of attacks and channel impairments. Further, it improves image quality with acceptable data rates. 

scholarly journals Iterative Decoding of Turbo Codes

2018 ◽  
Vol 3 ◽  
pp. 15
Author(s):  
Dhaneshwar Sah
Keyword(s):  
Turbo Codes ◽  
Coding Theory ◽  
Iterative Decoding ◽  
Communication Systems ◽  
Error Control ◽  
Viterbi Algorithm ◽  
Convolutional Codes ◽  
Soft Information ◽  
Space Communications ◽  
College Of Engineering

<p><strong> </strong>This paper presents a Thesis which consists of a study of turbo codes as an error-control Code and the software implementation of two different decoders, namely the Maximum a Posteriori (MAP), and soft- Output Viterbi Algorithm (SOVA) decoders. Turbo codes were introduced in 1993 by berrouet at [2] and are perhaps the most exciting and potentially important development in coding theory in recent years. They achieve near- Shannon-Limit error correction performance with relatively simple component codes and large interleavers. They can be constructed by concatenating at least two component codes in a parallel fashion, separated by an interleaver. The convolutional codes can achieve very good results. In order of a concatenated scheme such as a turbo codes to work properly, the decoding algorithm must affect an exchange of soft information between component decoders. The concept behind turbo decoding is to pass soft information from the output of one decoder to the input of the succeeding one, and to iterate this process several times to produce better decisions. Turbo codes are still in the process of standardization but future applications will include mobile communication systems, deep space communications, telemetry and multimedia. Finally, we will compare these two algorithms which have less complexity and which can produce better performance.</p><p><strong>Journal of Advanced College of Engineering and Management</strong>, Vol.3, 2017, Page: 15-30</p>

scholarly journals Channel Coding in Optical Communication Systems

2016 ◽  
Vol 4 (2) ◽  
pp. 1-5
Author(s):  
Viktor Durcek ◽  
◽  
Michal Kuba ◽  
Milan Dado
Keyword(s):  
Error Correction ◽  
Optical Networks ◽  
Optical Communication ◽  
Channel Coding ◽  
Communication Systems ◽  
High Speed ◽  
Forward Error Correction ◽  
Error Correcting Codes ◽  
Optical Communication Systems ◽  
Forward Error

In this paper, an overview of various types of error-correcting codes is present. Three generations of forward error correction methods used in optical communication systems are listed and described. Forward error correction schemes proposed for use in future high-speed optical networks can be found in the third generation of codes.

scholarly journals Robust IPTV Delivery with Adaptive Rateless Coding over a Mobile WiMAX Channel

2011 ◽  
Vol 2011 ◽  
pp. 1-11 ◽  
Author(s):  
Laith Al-Jobouri ◽  
Martin Fleury ◽  
Mohammad Ghanbari
Keyword(s):  
Channel Coding ◽  
Forward Error Correction ◽  
Content Management ◽  
Mobile Wimax ◽  
Application Layer ◽  
Ieee 802.16E ◽  
Coding Schemes ◽  
Redundant Data ◽  
Trade Offs ◽  
Forward Error

As intelligent content management of IPTV moves popular material nearer to the end-user, application-layer channel coding schemes, involving the retransmission of extra redundant data, become attractive as a result of the reduced latency. Application-layer, adaptive rateless channel coding is exploited in this paper's scheme to reconstruct streamed video across an IEEE 802.16e (mobile WiMAX) channel. The paper concentrates on the trade-offs in implementing the scheme, showing that exact calculation of the redundant data has the potential to reduce the forward error correction bit-rate overhead. To reduce delay, an appropriate compression rate should also be selected.

Error Rate Performance of Potential Multicarrier Waveforms and Coding Techniques for 5G

2020 ◽  
Vol 10 (2) ◽  
pp. 231-247
Author(s):  
Bhanu Priya ◽  
Jyoteesh Malhotra
Keyword(s):  
Error Rate ◽  
Communication Systems ◽  
Rate Performance ◽  
Parity Check ◽  
Throughput Performance ◽  
Modulation Formats ◽  
Coding Schemes ◽  
Low Density Parity Check ◽  
Cellular Environment ◽  
Parity Check Codes

Background: The wisdom of future wireless communication is clearly highlighted by the gigabit experience, low latency and the three fold rises in the capacity, compared to the 4th Generation networks. To meet such an ambitious objective of the 5th Generation communication systems, efficient use of non-contiguous unused spectrum is required. The panacea to this issue lies in the symbiosis of multicarrier waveforms and coding schemes. Methods: To study the interaction between these two, several multicarrier waveforms like Filtered- OFDM (F-OFDM), Universal Filtered Multi-Carrier (UFMC) and Weighted Overlap and Add (WOLA) which act as a powerful contender to win the 5G candidate waveform race, are analyzed in Low-Density Parity Check Codes (LDPC), Polar and Turbo coded representative Third Generation Partnership Project (3GPP) channel models under a common numerology framework. This article dwells upon the error rate and throughput performance of different modulation formats and coding schemes appropriate for the 5G in a well-defined multi-cellular environment. Results and Conclusion: The results have shown that even though many waveforms and coding techniques may pave the route towards its adoption as a physical layer standard instead of classical OFDM and convolution codes but no one is a clear conqueror as their selection depends upon the considered environment and type of traffic.

Performance Analysis of Turbo Codes Over AWGN Channel

2019 ◽  
Vol 19 (1) ◽  
pp. 43-48 ◽  
Author(s):  
Mohanad Abdulhamid ◽  
Mbugua Thairu
Keyword(s):  
Error Correction ◽  
Turbo Codes ◽  
Channel Coding ◽  
Turbo Coding ◽  
The Past ◽  
Coding Schemes ◽  
Awgn Channel ◽  
Correction Technique ◽  
Simple Component ◽  
Tremendous Impact

AbstractTurbo coding is a very powerful error correction technique that has made a tremendous impact on channel coding in the past two decades. It outperforms most known coding schemes by achieving near Shannon limit error correction using simple component codes and large interleavers. This paper investigates the turbo coder in detail. It presents a design and a working model of the error correction technique using Simulink, a companion softwareto MATLAB. Finally, graphical and tabular results are presented to show that the designed turbo coder works as expected.

scholarly journals Comparison between Different Channel Coding Techniques for IEEE 802.11be within Factory Automation Scenarios

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 7209
Author(s):  
Lorenzo Fanari ◽  
Eneko Iradier ◽  
Iñigo Bilbao ◽  
Rufino Cabrera ◽  
Jon Montalban ◽  
...  
Keyword(s):  
Turbo Codes ◽  
Channel Coding ◽  
Additive White Gaussian Noise ◽  
Convolutional Codes ◽  
Polar Codes ◽  
Wireless System ◽  
Factory Automation ◽  
Require Time ◽  
New Radio

This paper presents improvements in the physical layer reliability of the IEEE 802.11be standard. Most wireless system proposals do not fulfill the stringent requirements of Factory Automation use cases. The harsh propagation features of industrial environments usually require time retransmission techniques to guarantee link reliability. At the same time, retransmissions compromise latency. IEEE 802.11be, the upcoming WLAN standard, is being considered for Factory Automation (FA) communications. 802.11be addresses specifically latency and reliability difficulties, typical in the previous 802.11 standards. This paper evaluates different channel coding techniques potentially applicable in IEEE 802.11be. The methods suggested here are the following: WLAN LDPC, WLAN Convolutional Codes (CC), New Radio (NR) Polar, and Long Term Evolution (LTE)-based Turbo Codes. The tests consider an IEEE 802.11be prototype under the Additive White Gaussian Noise (AWGN) channel and industrial channel models. The results suggest that the best performing codes in factory automation cases are the WLAN LDPCs and New Radio Polar Codes.

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