scholarly journals Adding a Rate-1 Third Dimension to Parallel Concatenated Systematic Polar Code: 3D Polar Code

2018 ◽  
Vol 2018 ◽  
pp. 1-6
Author(s):  
Zhenzhen Liu ◽  
Kai Niu ◽  
Chao Dong ◽  
Jiaru Lin
Keyword(s):  
Full Advantage ◽  
Information Transfer ◽  
Three Dimensional ◽  
Error Floor ◽  
Extrinsic Information ◽  
Exit Chart ◽  
Convergence Behavior ◽  
Polar Code ◽  
Simulation Results ◽  
Third Dimension

In this paper, a three-dimensional polar code (3D-PC) scheme is proposed to improve the error floor performance of parallel concatenated systematic polar code (PCSPC). The proposed 3D-PC is constructed by serially concatenating the PCSPC with a rate-1 third dimension, where only a fraction λ of parity bits of PCSPC are extracted to participate in the subsequent encoding. It takes full advantage of the characteristics of parallel concatenation and serial concatenation. In addition, the convergence behavior of 3D-PC is analyzed by the extrinsic information transfer (EXIT) chart. The convergence loss between PCSPC λ=0 and different λ provides the reference for choosing the value of λ for 3D-PC. Finally, the simulation results confirm that the proposed 3D-PC scheme lowers the error floor.

scholarly journals Convergence analysis of the unpunctured turbo trellis-coded modulation (UTTCM)

2019 ◽  
Vol 13 (2) ◽  
pp. 447
Author(s):  
Ahmed Haffane ◽  
Abdelhafid Hasni ◽  
Mustapha Khelifi ◽  
Boufeldja Kadri
Keyword(s):  
Gaussian Noise ◽  
Iterative Decoding ◽  
Information Transfer ◽  
Additive White Gaussian Noise ◽  
Coded Modulation ◽  
Extrinsic Information ◽  
Trellis Coded Modulation ◽  
Exit Chart ◽  
Trellis Coded ◽  
Simulation Results

In this paper, the performance of the Unpunctured Turbo Trellis-Coded Modulation (UTTCM) over Additive White Gaussian Noise (AWGN) channel is analyzed using the non-binary extrinsic information transfer (EXIT) chart. The exchange of the extrinsic information between the decoder components is tracked, allowing the generation of an EXIT chart, which is a powerful tool for analyzing the convergence behavior of iterative decoding and prediction of convergence position. The Simulation results are compared with the turbo cliff positions on the BER curves.

scholarly journals Improving Polar-Coded SCMA System by Information Coupling and Parity Check

Sensors ◽  
2020 ◽  
Vol 20 (23) ◽  
pp. 6740
Author(s):  
Xi Wu ◽  
Yafeng Wang
Keyword(s):  
Information Transfer ◽  
Multiple Access ◽  
Iterative Detection ◽  
Bayes Rule ◽  
Parity Check ◽  
Extrinsic Information ◽  
Polar Code ◽  
Successive Cancellation ◽  
Simulation Results ◽  
Encoding Method

In this paper, the uplink information-coupled polar-coded sparse code multiple access (PC-SCMA) system is proposed. For this system, we first design the encoding method of systematic joint parity check and CRC-aided (PCCA) polar code. Using the systematic PCCA-polar code as base code, the partially information-coupled (PIC) polar code is constructed. Then, a joint iterative detection and successive cancellation list (SCL)-decoding receiver is proposed for the PC-SCMA system. For the receiver, the coupled polar decoder’s extrinsic messages are calculated by the Bayes rule and soft cancellation (SCAN) algorithm. Based on the extrinsic information transfer (EXIT) idea, the PIC PCCA-polar code is optimized. Simulation results demonstrate that the PIC PCCA-PC-SCMA system outperforms the other polar (or LDPC) coded SCMA systems at various code rates and channel configurations. Additionally, compared with an uncoupled PC-SCMA system with SCL decoder, the complexity of PIC PCCA-PC-SCMA is reduced at a high Eb/N0

scholarly journals On efficient designing of protograph LDPC codes

2021 ◽  
Vol 19 (6.2) ◽  
pp. 39
Author(s):  
Huong-Giang Nguyen ◽  
Nghia Xuan Pham ◽  
Thu Phuong Nguyen ◽  
Chi Dinh Nguyen
Keyword(s):  
Information Transfer ◽  
Ldpc Codes ◽  
Code Rate ◽  
Weight Enumerator ◽  
Error Floor ◽  
Extrinsic Information ◽  
Simple Method ◽  
Prior Art ◽  
Simulation Results

This paper designs two protograph LDPC codes with code-rate $R > 1/2$. A simple method using the protograph extrinsic information transfer (PEXIT) to design the codes with a low decoding threshold and the asymptotic weight enumerator (AWE) to evaluate the error floor of the codes is deployed. Simulation results show that the proposed codes have a better error floor than prior art protograph codes and offer higher rate protographs.

Application of Extrinsic Information Transfer Charts to Anticipate Turbo Code Behavior

2013 ◽  
pp. 97-104
Author(s):  
Izabella Lokshina
Keyword(s):  
Turbo Codes ◽  
Iterative Decoding ◽  
Information Transfer ◽  
Turbo Code ◽  
A Priori ◽  
Substantial Reduction ◽  
International Standards ◽  
Extrinsic Information ◽  
Exit Chart ◽  
Analysis Technique

This paper examines turbo codes that are currently introduced in many international standards, including the UMTS standard for third generation personal communications and the ETSI DVB-T standard for Terrestrial Digital Video Broadcasting. The convergence properties of the iterative decoding process associated with a given turbo-coding scheme are estimated using the analysis technique based on so-called extrinsic information transfer (EXIT) chart. This approach provides a possibility to anticipate the bit error rate (BER) of a turbo code system using only the EXIT chart. It is shown that EXIT charts are powerful tools to analyze and optimize the convergence behavior of iterative systems utilizing the turbo principle. The idea is to consider the associated SISO stages as information processors that map input a priori LLR’s onto output extrinsic LLR’s, the information content being obviously assumed to increase from input to output, and introduce them to the design of turbo systems without the reliance on extensive simulation. Compared with the other methods for generating EXIT functions, the suggested approach provides insight into the iterative behavior of linear turbo systems with substantial reduction in numerical complexity.

Application of Extrinsic Information Transfer Charts to Anticipate Turbo Code Behavior

2011 ◽  
Vol 3 (2) ◽  
pp. 31-37 ◽  
Author(s):  
Izabella Lokshina
Keyword(s):  
Turbo Codes ◽  
Iterative Decoding ◽  
Information Transfer ◽  
Turbo Code ◽  
A Priori ◽  
Substantial Reduction ◽  
International Standards ◽  
Extrinsic Information ◽  
Suggested Approach ◽  
Exit Chart

This paper examines turbo codes that are currently introduced in many international standards, including the UMTS standard for third generation personal communications and the ETSI DVB-T standard for Terrestrial Digital Video Broadcasting. The convergence properties of the iterative decoding process associated with a given turbo-coding scheme are estimated using the analysis technique based on so-called extrinsic information transfer (EXIT) chart. This approach provides a possibility to anticipate the bit error rate (BER) of a turbo code system using only the EXIT chart. It is shown that EXIT charts are powerful tools to analyze and optimize the convergence behavior of iterative systems utilizing the turbo principle. The idea is to consider the associated SISO stages as information processors that map input a priori LLR’s onto output extrinsic LLR’s, the information content being obviously assumed to increase from input to output, and introduce them to the design of turbo systems without the reliance on extensive simulation. Compared with the other methods for generating EXIT functions, the suggested approach provides insight into the iterative behavior of linear turbo systems with substantial reduction in numerical complexity.

Instrumentation For Quantitative Microscopy

1977 ◽  
Vol 35 ◽  
pp. 206-209
Author(s):  
B. Ralph ◽  
A.R. Jones
Keyword(s):  
Volume Fraction ◽  
Three Dimensional ◽  
Two Dimensional ◽  
Automatic Data ◽  
Phase Volume Fraction ◽  
Statistical Confidence ◽  
Resultant Data ◽  
Automatic Data Collection ◽  
Third Dimension ◽  
Evolution Of Microstructure

In all fields of microscopy there is an increasing interest in the quantification of microstructure. This interest may stem from a desire to establish quality control parameters or may have a more fundamental requirement involving the derivation of parameters which partially or completely define the three dimensional nature of the microstructure. This latter categorey of study may arise from an interest in the evolution of microstructure or from a desire to generate detailed property/microstructure relationships. In the more fundamental studies some convolution of two-dimensional data into the third dimension (stereological analysis) will be necessary.In some cases the two-dimensional data may be acquired relatively easily without recourse to automatic data collection and further, it may prove possible to perform the data reduction and analysis relatively easily. In such cases the only recourse to machines may well be in establishing the statistical confidence of the resultant data. Such relatively straightforward studies tend to result from acquiring data on the whole assemblage of features making up the microstructure. In this field data mode, when parameters such as phase volume fraction, mean size etc. are sought, the main case for resorting to automation is in order to perform repetitive analyses since each analysis is relatively easily performed.

Design of finite-time guidance law based on observer and head-pursuit theory

2021 ◽  
pp. 095441002098456
Author(s):  
Chenqi Zhu
Keyword(s):  
Finite Time ◽  
Three Dimensional ◽  
Hypersonic Vehicle ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Reaching Law ◽  
Guidance Law ◽  
Fast Power ◽  
Simulation Results ◽  
Guidance Laws

In order to improve the guiding accuracy in intercepting the hypersonic vehicle, this article presents a finite-time guidance law based on the observer and head-pursuit theory. First, based on a two-dimensional model between the interceptor and target, this study applies the fast power reaching law to head-pursuit guidance law so that it can alleviate the chattering phenomenon and ensure the convergence speed. Second, target maneuvers are considered as system disturbances, and the head-pursuit guidance law based on an observer is proposed. Furthermore, this method is extended to a three-dimensional case. Finally, comparative simulation results further verify the superiority of the guidance laws designed in this article.

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