Abstract

With the development of the mobile communication, the related technologies have gone through a rapid growing phase from 1G to 3G, until 4G. The technology evolution targets to improve the performance of overall system, and promote the related services and applications. In this paper, author makes analysis on Turbo equalization based on M-QAM modulation in OFDM system. Since Turbo equalization is an iterative receiver algorithm repeating equalization and channel decoding to improve the performance of the receiver, there researches on Turbo codes and turbo equalization have been emphasis, especially on the error-correction during these years. Due to the operations of equalization and decoding are repeated several times in one process, the computational complexity is increased in the receiver. Author aims at the cost function of CMA (Constant Modulus Algorithm) to change or recreate a new algorithm, and then as a contrast with the error functions, we can see the advantages about this change. Finally, author makes simulations on the Turbo equalization based on 64-QAM in OFDM system. Compared with the Turbo equalization based on 16-QAM, the performance of Turbo equalization based on 64-QAM is more efficient.

Keywords:

CMA (Constant Modulus Algorithm), DFE (Decision Feedback Equalizer), MMSE (Minimum Mean Square Error), OFDM (Orthogonal Frequency Division Multiplexing), Turbo Equalization, 64-QAM,

References

Competing interests

The authors have no competing interests.

Open Access Policy

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Copyright

The authors have no competing interests.