Signal processing method applied to optical non-Hermitian symmetric OFDM receiver

Abstract

The invention discloses a signal processing method applied to an optical non-Hermitian symmetric OFDM receiver, and the method comprises the following steps: after timing synchronization is finished, directly carrying out real number FFT operation on a received signal without recovering a corresponding complex signal again, so the calculation complexity is reduced; adopting a single training sequence, on the basis of a traditional LS channel estimation method, carrying out the subcarrier pairing average processing on the basis that preliminary channel estimation on all data subcarriers is obtained, so the system noise interference is restrained, and the accuracy of channel estimation is improved; and finally, carrying out channel equalization processing on the received data by utilizing the channel estimation after the pairing and averaging, and reconstructing a received QAM symbol. According to the non-Hermitian symmetric orthogonal frequency division multiplexing receiver, the hardware implementation complexity of the non-Hermitian symmetric orthogonal frequency division multiplexing receiver can be reduced by replacing the traditional complex FFT algorithm with the real FFT algorithm, and in addition, the accuracy of channel estimation can be improved by using the channel estimation algorithm based on subcarrier pairing average, so the performance of the receiver is improved.

Description

technical field [0001] The invention relates to the field of optical communication, in particular to a signal processing method applied to an optical non-Hermitian symmetric OFDM receiver. Background technique [0002] Intensity Modulated Direct Detected Optical OFDM (IMDDO-OFDM) technology has been widely studied and applied to short-distance optical networks, such as passive optical networks and Data center optical interconnection. In traditional IMDDO-OFDM systems, digital or analog up-conversion is required to generate real OFDM signals. Therefore, more on-chip resources or additional data converters and mixers are required, resulting in increased hardware implementation complexity. In addition, the method of using the Hermitian symmetry (HS) characteristic of the FFT algorithm to generate a real baseband OFDM signal is relatively simple because it does not require up-conversion processing. However, in the baseband HS-OFDM transceiver, only half of the subcarriers can ...

AI Technical Summary

Problems solved by technology

However, in the optical communication system, due to the imperfect frequency of optoelectronic devices and the influence of various interferences, the channel response on adjacent subcarriers may be quite different. At this time, the ISFA method will not be able to effectively improve the accuracy of channel estimation.

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