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Performance Analysis of High Throughput map Decoder for Turbo Codes and Self Concatenated Convolutional Codes

IEEE ACCESS 2019年 7卷 138079-138093页

作者： Shaheen, Farzana Butt, Muhammad Fasih Uddin Agha, Shahrukh Ng, Soon Xin Maunder, Robert G. COMSATS Univ Islamabad Dept Elect & Comp Engn Islamabad 45550 Pakistan Univ Southampton Sch Elect & Comp Sci Southampton SO17 1BJ Hants England

The effect of parallelism on Bit Error Rate (BER) performance of Turbo Code (TC) and Self Concatenated Convolutional Code (SECCC) with different levels of parallelism and frame sizes is investigated. Next Iteration Initialization (NII) method is employed for mitigating the BER degradation resulting from increased parallelism. In order to analyze and compare the architectural performance of both schemes, this paper presents the Very High Speed Integrated Circuit Hardware Description Language (VHDL) design of Maximum Aposteriori Probability (map) decoder for TC and SECCC, both employing the same constituent code. The simulation results show that for BER of 10(-4), without parallelism, TC is 0.4 dB superior to SECCC, whereas, with parallelism of 64, the difference in performance between both schemes reduces to 0.25 dB. It is found that SECCC outperforms TC for frame sizes less than or equal to 2048 bits, when invoking a parallelism of 16, 32 and 64. The BER performance of both schemes shows that SECCC outperforms TC at parallelism of 256 by 0.3 dB at BER of 10(-4). Hence, for high throughput architectures employing higher parallelism (beyond 64 and 128) without significant degradation in BER performance, SECCC performs better than TC. The synthesis results of VHDL design of the map decoder obtained using Xilinx ISE verify that both schemes have equal clock frequency and resource consumption. It is demonstrated that the map decoder achieves the clock frequency of 86.3 MHz which is capable of producing a throughput of 691 Mbps using parallelism of 64.

关键词： Decoding Parallel processing Throughput Bit error rate Iterative decoding Convolutional codes VHDL map algorithm high throughput bit error rate parallelism SECCC turbo codes VHDL

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Feature Extraction Method for EEG Waves by Using map Detector of Input Signals with Multi-Discrete-Level Amplitude

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IFAC Proceedings Volumes 1997年第11期30卷 1269-1274页

作者： Katsuhiro Inoue Kousuke Kumamaru Shigeaki Matsuoka Medical Association Showa Hospital Simonoseki 750 Japan

In this paper, a dynamical model is introduced to develop a new automatic stage determination system of human sleep electroencephalogram (EEG) not using the wave pattern recognition step. The EEG generating mechanism is modeled by a damped system excited by impulse input process which subjects to Poisson process whose amplitude has a transition property. Furthermore, A Maximum A Posteriori (map) method is modified to be applicable to the model. We can then extract useful information which is directly related to sleep stages based on the model and map detector.

关键词： Bayes methods map algorithm Electroencephalogram State estimation Kalman filter Human EEG sleep stages

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Finite wordlength analysis and adaptive decoding for Turbo/map decoders

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JOURNAL OF VLSI SIGNAL PROCESSING SYSTEMS FOR SIGNAL IMAGE AND VIDEO TECHNOLOGY 2001年第3期29卷 209-221页

作者： Wang, ZF Suzuki, H Parhi, KK Univ Minnesota Dept Elect & Comp Engn Minneapolis MN USA Kawasaki Steel Corp LSI Div Chiba 260 Japan

Turbo decoders inherently require large hardware for VLSI implementation as a large amount of memory is required to store incoming data and intermediate computation results. Design of highly efficient Turbo decoders requires reduction of hardware size and power consumption. In this paper, finite precision effects on the performance of Turbo decoders are analyzed and the optimal word lengths of variables are determined considering tradeoffs between the performance and the hardware cost. It is shown that the performance degradation from the infinite precision is negligible if 4 bits are used for received bits and 6 bits for the extrinsic information. The state metrics normalization method suitable for Turbo decoders is also discussed. This method requires small amount of hardware and its speed does not depend on the number of states. Furthermore, we propose a novel adaptive decoding approach which does not lead to performance degradation and is suitable for VLSI implementation.

关键词： VLSI implementation turbo codes adaptive decoding map algorithm

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Trellis demodulator for pulse shaped OFDM

Trellis demodulator for pulse shaped OFDM

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IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)

作者： Rashich, Andrey Kislitsyn, Alexandr Gorbunov, Sergei Peter Great St Petersburg Polytech Univ Radio & Telecommun Syst Dept St Petersburg Russia

ISBN: (纸本)9781538670910

A trellis demodulator for spectrally efficient pulse shaped OFDM-signals is proposed. Its' performance is analyzed for a set of optimal pulses obtained as the solution of the optimization problem with restriction to a certain spectrum reduction rate. We consider the pulse shapes of general form with duration equal to OFDM-symbol duration. The iterative version of trellis demodulator for pulse shaped OFDM with FEC is also proposed. The BER performance of proposed iterative demodulator of spectrally efficient pulse shaped OFDM signals is comparable with the one of classic coded OFDM modulation with the same FEC. The performance of proposed algorithms does not depend on the number of subcarriers. They allow to introduce non-orthogonality into OFDM to achieve very good spectral characteristics with small BER degradation.

关键词： OFDM PS-OFDM GFDM iterative receiver map algorithm 5G OOBE

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On the iterative decoding of concatenated partial unit memory codes structures

On the iterative decoding of concatenated partial unit memor...

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1st International Symposium on Wireless Communication Systems (ISWCS 04)

作者： Fagoonee, L Honary, B Univ Lancaster Fac Sci Appl Dept Commun Syst Lancaster LA1 4YW England

ISBN: (纸本)0780384725

The aim of this paper is to describe in detail the iterative decoding algorithm used during the implementation of concatenated Partial Unit Memory (PUM) code structures, such as turbo and woven turbo constructions based on PUM codes. Previous published research by the authors have shown that such concatenated PUM code structures have better distance properties and performance than equivalent structures based on convolutional codes. The decoding algorithm presented is based on the max-log map algorithm used for classical turbo codes with component convolutional codes. Unlike the trellis of a convolutional code, the trellis of PUM codes is characterised by parallel branches between state pairs and multiple input branch labels. We show how the original max-log map algorithm is adapted to cope with the unusual trellis structure of PUM codes. The proof that our algorithm performs satisfactorily is illustrated by the relative performance, for different iterations, of turbo and woven turbo structures based on PUM codes, which approach the Shannon limit.

关键词： iterative decoding map algorithm turbo codes woven turbo codes PUM codes

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An Optimized Resource Efficient Approximation of max* Operator for Recalculation in Turbo Code Decoder 5

An Optimized Resource Efficient Approximation of <i>max</i>*...

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5th International Conference on Enterprise Systems (ES) - Industrial Digitalization by Enterprise Systems

作者： Zhan, Ming Wu, Jun Wen, Hong Southwest Univ Sch Elect & Informat Engn Chongqing 400715 Peoples R China Shanghai Jiao Tong Univ Sch Cyber Secur Shanghai 200240 Peoples R China Univ Elec Sci & Tech China Natl Key Lab Sci & Tech Comm Chengdu 611731 Sichuan Peoples R China

ISBN: (纸本)9781538609361

A family of powerful and resource efficient Turbo codes is developed for sensor networks. In the hardware realization of Turbo code decoder, recalculation of the forward or backward state metrics is an effective method to reduce the size of state metrics cache. To facilitate recalculation of the state metrics, an optimized max* operator is presented in this paper. Calculation of the proposed max* operator includes two correction terms, and each one is approximated by using simple comparing, shifting and addition operations. Moreover, approximation of the proposed max* operator is specially optimized for reverse calculation. Although there is small error in the reverse calculation, it has been shown that the maximum error is about three percent, and the proposed approximation is validity for reverse calculation.

关键词： Turbo code map algorithm max* operator recalculation approximation

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Improved Coding Gain of Clipped OFDM Signal using Avalanche Effect of AES Block Cipher

Improved Coding Gain of Clipped OFDM Signal using Avalanche ...

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IEEE Pacific Rim Conference on Communications, Computers and Signal Processing (PACRIM)

作者： El-Ganiny, M. Youssef ElAttar, Hussein M. Dahab, Mohamed A. Aboul Elgarf, Talaat A. Higher Technol Inst Elect & Comp Engn Dept Ramadan City 10 Egypt Arab Acad Sci Technol & Maritime Transport Elect & Commun Engn Dept Alexandria Egypt

ISBN: (纸本)9781538607008

Although Orthogonal Frequency Division Multiplexing (OFDM) seems to be a solution to achieve the demand of high data rates and immunity to the multipath fading channel, it has some drawbacks. High Peak to average power ratio (PAPR) is the most significant problem of these drawbacks. The main objective of this paper is to introduce a modified PAPR reduction technique named as samples clipping and then use a new channel coding approach to enhance the Bit Error Rate (BER) performance with a degree of complexity. This approach is performed by enhancing the cooperation between soft decision decoding and cryptography. This approach is also performed with Binary Phase Shift Key (BPSK) and Quadrature Phase Shift Key (QPSK) modulation techniques. The PAPR and BER performance calculations for the proposed system are investigated and validated by MATLAB simulation results. These results are evaluated under Additive White Gaussian Noise (AWGN) in addition to Rayleigh and Rician Fading channels.

关键词： OFDM PAPR Channel coding map algorithm AES Avalanche Effect SIE algorithm SID algorithm

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How tracer objects can improve competitive learning algorithms in astronomy

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Vistas in Astronomy 1994年第PART 3期38卷 317-330页

作者： Hernandez-Pajares, M. Floris, J. Murtagh, F. Department Matemàtica Aplicada i Telemàtica Univ. Politècnica de Catalunya E08080 Barcelona Apartat 30002 Spain Space Telescope-European Coordinating Facility European Southern Observatory D-85748 Garching Karl-Schwarzschild-Str. 2 Germany

The main objective of this paper is to discuss how the use of tracer objects in competitive learning can improve results in stellar classification. To do this, we work with a Kohonen network applied to a reduced sample of the Hipparcos Input Catalogue, which contains missing values. The use of synthetic stars as tracer objects allows us to determine the discrimination quality and to find the best final values of the cluster centroids, or neuron weights. © 1995.

关键词： classification Data analysis Galaxy (the) map algorithm Neural networks Self-Organizing Feature Solar neighbourhood Stars

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Optimal Input Power Backoff of a Nonlinear Power Amplifier for FFT-Based Trellis Receiver for SEFDM Signals 16th

Optimal Input Power Backoff of a Nonlinear Power Amplifier f...

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16th International Conference on Next Generation Teletraffic and Wired/Wireless Advanced Networks and Systems (NEW2AN) / 9th Conference on Internet of Things and Smart Spaces Are You Smart (ruSMART)

作者： Rashich, Andrey Fadeev, Dmitrii Peter Great St Petersburg Polytech Univ St Petersburg Russia

ISBN: (纸本)9783319463018;9783319463001

In this paper BER performance of FFT-based trellis receiver for multicarrier signals with spectrally efficient frequency division multiplexing (SEFDM) is evaluated taking into account the impact of nonlinear distortions caused by nonlinear power amplifier (PA). Values of input power back-off (IBO) corresponding to the best BER performance are obtained. The energy efficiency is quantified with energy loss with respect to the system with ideal linear PA. The energy efficiency of considered system is compared with the one of SEFDM system with detection algorithm based on decision diagram and no coding.

关键词： OFDM SEFDM BER performance Input back-off IBO Iterative receiver map algorithm 5G

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PERFORMANCE COMPARISON OF TURBO CODES WITH LDPC CODES AND WITH BCH CODES FOR FORWARD ERROR CORRECTING CODES

PERFORMANCE COMPARISON OF TURBO CODES WITH LDPC CODES AND WI...

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IEEE Student Conference on Research and Development (SCOReD)

作者： Alwan, Mohammed Hasan Singh, Mandeep Mahdi, Hussain Falih Univ Kebangsaan Malaysia Fac Engn & Built Environm Dept Elect Elect & Syst Bangi Malaysia Univ Diyala Comp & Software Engn Dept Baqubah Iraq

ISBN: (纸本)9781467395724

In the field of communication, one of the most thriving and prevalent subject is the channel coding. Channel coding generally deals with the bandwidth which is the bit-rate or information storage capacity. It is a technical field which relies heavily on cost. In fact, it is undeniable that cost is the most crucial element in every system. Nowadays, together with the latency or time element which is also an equally significant factor, especially in mobile communication. The objective of this paper is to analyse and compare distinctively the three types of codes namely, turbo codes, LDBC codes and BCH codes, all simulated respectively in MATLAB environment. According to the conducted studies, it is evident that the BCH codes are excellent in performance compared to other codes. The turbo code, despite requiring maximum processing to decode the message has fairly good performance as well. Regardless of the level of processing, all the codes possess good & reliable performances compared to other codes.

关键词： Channel coding Turbo code LDPC code map algorithm belief propagation BCH codes

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