Overlapped list successive cancellation approach for hardware efficient polar code decoder

Polar code has been proven to achieve the symmetric capacity of memoryless channels. However, the successive cancellation decoding algorithm is inherent serial in nature, which will lead to high latency and low throughput. In order to obtain high throughput, we design a deeply pipelined polar decoder and optimize the processing elements and storage structure. We also propose an improved fixed-point nonuniform quantization scheme, and it is close to the floating-point performance. Two-level control strategy is presented to simplify the controller. In addition, we adopt FIFO structure to implement the α_memory and β_memory and propose the 348-stage pipeline decoder.

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

Sensors ◽

10.3390/s20236740 ◽

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

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Internal pilot insertion for polar codes

Indonesian Journal of Electrical Engineering and Computer Science ◽

10.11591/ijeecs.v22.i3.pp1495-1504 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1495

Author(s):

Walled K. Abdulwahab ◽

Abdulkareem A. Kadhim

Keyword(s):

Fading Channels ◽

Channel Coding ◽

Additive White Gaussian Noise ◽

Polar Codes ◽

Code Construction ◽

Performance Improvements ◽

Internal Pilot ◽

Polar Code ◽

Coding Schemes ◽

Successive Cancellation

Two internal pilot insertion methods are proposed for polar codes to improve their error correction performance. The presented methods are based on a study of the weight distribution of the given polar code. The insertion of pilot bits provided a new way to control the coding rate of the modified polar code on the basis of the Hamming weight properties without sacrificing the code construction and the related channel condition. Rate control is highly demanded by 5G channel coding schemes. Two short-length polar codes were considered in the work with successive cancellation list decoding. The results showed that advantages in the range of 0.1 to 0.75 dB were obtained in the relative tolerance of the modified coded signal to the additive white Gaussian noise and fading channels at a bit error rate of 10<sup>−4</sup>. The simulation results also revealed that the performance improvements were possible with a careful insertion of the pilots. The modified polar code with pilot insertion provided performance improvement and offered the control of the coding rate without any added complexity at both the encoder and the decoder.

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Design of Approximate Polar Maximum-Likelihood Decoder

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.b3336.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 5086-5092

Keyword(s):

Information Theory ◽

Median Filter ◽

Error Correcting Code ◽

Polar Codes ◽

Approximate Computing ◽

Noisy Channel ◽

Polar Code ◽

Successive Cancellation ◽

Decoder Architecture

Polar codes, presented by Arikan, accomplish the ability to acquire nearly error-less communication for any given noisy channel of symmetry with "low encoding and decoding complexities" on a huge set of fundamental channels. As of late, polar code turned into the best ideal error-correcting code from the perspective of information theory because of its quality of channel achieving capacity. Though the successive cancellation decoder with approximate computing is efficient, the proposed ML-based decoder is more efficient than the former. As it is equipped with the Modified Processing Element which shows the better performance with the properties of Median Filter. The proposed ML-based decoder diminishes the area and power consumed and logic utilization. In the present paper, effective polar decoder architecture is structured and executed on FPGA utilizing Vertex 5. Here we examine the proposed unique construction that is appropriate for decoding lengthy polar codes with less equipment multifaceted nature.

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