Physical layer preamble and pilot-based channel equalization method and system

Abstract

The invention discloses a physical layer preamble and pilot-based channel equalization method and a physical layer preamble and pilot-based channel equalization system. The method comprises the following steps: extracting preamble symbols of received data frames to acquire a received preamble sequence; according to the received preamble sequence, calculating an amplitude compensating factor; extracting data symbols of the received data frames, determining plural elements at the pilot positions of the data symbols, and acquiring a received data symbol pilot sequence; according to the received data symbol pilot sequence and a preset pilot sequence, calculating a phase compensating factor; and according to the acquired amplitude compensating factor and the phase compensating factor, performing amplitude compensation and phase compensation on the data influenced by a channel. In the method and the system, the preambles and pilots in the data symbols are fully utilized, the channel estimation is performed by amplitude compensation and phase compensation methods so as to well compensate phase change due to signal transmission, and better equalization effect is achieved with lower complexity.

Description

technical field [0001] The invention relates to the field of wireless communication, in particular to a channel equalization method and system based on a physical layer preamble and a pilot in orthogonal frequency division multiplexing. Background technique [0002] Orthogonal Frequency Division Multiplexing (OFDM) is the industry-recognized core technology in the next-generation wireless communication system. Because it has good anti-multipath and anti-frequency selective fading characteristics, it is adopted by many wireless communication standards. , such as DAB, DVB-T, IEEE802.11a, IEEE802.16e. [0003] In wideband OFDM systems, the receiver needs channel estimation and equalization after frame synchronization and frequency offset estimation. Since the signal experiences frequency-selective fading on the entire system bandwidth and flat fading on each subcarrier, the receiving end can perform frequency-domain equalization on the data. Frequency domain equalization has ...

AI Technical Summary

Problems solved by technology

The IEEE802.16-2004 frame structure stipulates the preamble, which can be used as the training sequence for non-blind estimation of the channel during channel equalization, but this estimation method only has a good effect on the slow fading channel and cannot Adapt to faster changes in the channel

Therefore, in a relatively harsh wireless channel environment, the phase of the signal is prone to change during transmission, which in turn affects the channel balance.

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