Phase noise suppression method under low-complexity channel estimation of SC-FDE (single carrier-frequency domain equalization) system

Abstract

The invention discloses a phase noise suppression method under the low-complexity channel estimation of an SC-FDE (single carrier-frequency domain equalization) system. The phase noise suppression method comprises the following steps of: forming a training sequence by virtue of special characters, obtaining the responses of a small amount of frequency points of CFR (crest factor reduction) and a CIR (channel impulse response) by virtue of a LS (least square) algorithm according to the received signal, obtaining the initial CFR influenced by a phase noise CPE (common phase error) via a discrete Fourier transform interpolation filter, and performing time-domain noise power estimation and frequency-domain noise power estimation according to the training sequence; after an established channel is obtained, extracting the effective order of the CIR in a time domain, and calculating the copy of the special character received signal; using special characters as cyclic prefixes of transmission data blocks, estimating the ratio of the CPE on one cyclic prefix to the CPE in the initial established channel by virtue of an MMSE (minimum mean square error) algorithm, and then obtaining the ratio of the CPE of the whole data block to the CPE in the initial established channel via linear interpolation; and finally multiplying the CPE ratio with the initial CIR influenced by the phase noise CPE to track the whole channel of the present data block, and suppressing phase noise interference via the frequency-domain MMSE equalization. The channel estimation algorithm disclosed by the invention is low in complexity, thus reducing the complexity of a phase noise suppression algorithm.

Description

technical field

[0001] The invention belongs to the technical field of wireless communication, and more specifically relates to a method for suppressing phase noise under low-complexity channel estimation of an SC-FDE system. Background technique

[0002] Single-Carrier Frequency Domain Equalization (SC-FDE, Single-Carrier Frequency Domain Equalization) technology refers to the technology that the transmitter uses single-carrier modulation and the receiver uses frequency domain equalization. It, like Orthogonal Frequency Division Multiplexing (OFDM, Orthogonal Frequency Division Multiplexing) technology, is one of the technologies that greatly reduces the equalization complexity at the receiving end. Compared with OFDM, SC-FDE has the advantages of low peak-to-average power ratio (PAPR, Peak to Average Power Ratio) and insensitivity to carrier frequency offset (CFO, Carrier Frequency Offset). Therefore, many wireless communication standards, such as the uplink of the global...

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