Systems Engineering and Electronics ›› 2022, Vol. 44 ›› Issue (10): 3235-3242.doi: 10.12305/j.issn.1001-506X.2022.10.29

• Communications and Networks • Previous Articles     Next Articles

Parameter estimation algorithm of convolutional codes with solving cost function based on conjugate gradient

Zengmao CHEN1,2, Li LU1, Zhiguo SUN1,*, Rongchen SUN1   

  1. 1. School of Information and Communication Engineering, Harbin Engineering University, Harbin 150001, China
    2. Key Laboratory of Advanced Marine Communication and Information Technology, Ministry of Industry and Information Technology, Harbin 150001, China
  • Received:2021-07-13 Online:2022-09-20 Published:2022-10-24
  • Contact: Zhiguo SUN

Abstract:

Convolutional codes are often used as sub-codes of high performance codes such as concatenated codes and turbo codes. Correct parameter estimation of convolutional codes is the basis of recognition of concatenated codes and turbo codes, which requires that the estimation algorithms of convolutional codes should have strong robustness against channel noise. The key to such purpose is to make use of the soft-decesion demodulation received sequence. In this paper, a cost function model based on exponential function is proposed according to the linear constraint relation between symbols of recursive systematic convolutional codes. The parameter estimation of convolutional codes is transformed into the minimal value of the cost function. And the optimization is accomplished via a simple iterative process by conjugate gradient. Simulation results show that, compared with the existing algorithms, the new algorithm significantly improves the performance while it is also applicable to the estimation of general convolutional codes and has a fast convergence speed.

Key words: parameter estimation of convolutional codes, recursive systematic convolutional codes, soft-decision demodulation, optimization method, conjugate gradient method

CLC Number: 

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