Channel estimation method, frequency tracking method and multi-carrier receiver

Abstract

A mechanism for frequency tracking and channel estimation in multi-carrier systems. First, two training symbols are pre-compensated for an effect of frequency offset. Then an average of the two pre-compensated symbols is calculated. Meanwhile, a correlation between the two pre-compensated second symbols is evaluated by performing a differential operation. By means of a tracking loop, a frequency tracking value is calculated from the correlation and a loop coefficient. After that, the average of the two pre-compensated symbols is further compensated with a fine frequency offset estimate derivedfrom the frequency tracking value. Accordingly, a channel response is estimated by performing a Fourier transform on the compensated average.

Description

technical field The present invention relates to a communication system, in particular to frequency tracking and channel estimation of Orthogonal Frequency Division Multiplexing (OFDM). Background technique With the rapid growth of demand for mobile phones, mobile radios and other wireless transmission services, how to develop various technologies to provide reliable, secure and efficient wireless communication is becoming more and more important. Orthogonal Frequency Division Multiplexing (OFDM) is known as a highly spectrally efficient transmission method that can cope with severe channel impairments encountered in a mobile environment. OFDM was first used in wireless local area networks (WLANs) as part of the IEEE 802.11a standard in the 5GHz band. In addition, the IEEE 802.11g standard approved in June 2003 also adopts OFDM as a necessary part of the 2.4 GHz frequency band extension to the 802.11b standard for another high-speed physical layer (PHY). The basic concept...

AI Technical Summary

Problems solved by technology

OFDM signals are easily affected by frequency offset, which leads to the loss of orthogonality between OFDM subcarriers, as well as Inter-Carrier Interference (ICI) and Bit Error Rate (Bit Error Rate, BER) deterioration

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