Method for tracking carrier frequency of multiband orthogonal frequency division multiplexing (OFDM) ultra wideband system

Abstract

The invention aims at the problem of desynchrony of a transceiver oscillator of a multiband orthogonal frequency division multiplexing (OFDM) ultra wideband communication system, and provides a method for tracking the carrier frequency on the basis of a time-domain technology. A time-domain or frequency-domain type data symbol and a time-domain expansion symbol are utilized to estimate a first band frequency offset, a second band frequency offset and a third band frequency offset are derived after the filtering of a loop, the estimated values of the three frequency offsets are respectively input into a triple-path phase accumulator and an exponential function (exp) generator to form a triple-path compensating structure, a time-frequency code controls a feedback signal to be multiplied with the data in a time domain or a frequency domain and a forward path in a time division way, and accordingly, the frequency offset compensation is realized. The method does not need to use additional pilot frequency subcarriers, is beneficial to saving frequency spectrum, and can simultaneously realize better tracking performance than that of a traditional pilot frequency assistant method, the high precision estimation and compensation of small frequency offsets are realized, the desynchrony of the transceiver oscillator is made up, the system performance is guaranteed, and the method can be widely applied in multiband OFDM wireless communication systems which adopt a time-domain expansion diversity technology.

Description

technical field [0001] The invention relates to a carrier frequency tracking method based on time domain extension (TDS) technology of a multi-band OFDM ultra-wideband system, aiming at the carrier frequency deviation caused by the asynchronous oscillator in the system receiver and the transmitter, after the carrier frequency of the receiver is captured Further estimating and compensating the smaller residual carrier frequency offset can be widely used in multi-band OFDM wireless communication systems with time domain extension diversity technology. Background technique [0002] Ultra-wideband technology has the characteristics of high data throughput, low power spectral density, and strong anti-multipath ability. It is mainly used in high-speed short-distance wireless communication, and can be used in wireless personal area network, wireless multimedia interface, radar detection, precise positioning, and medical imaging. and other fields. Multiband Orthogonal Frequency Div...

AI Technical Summary

Problems solved by technology

The incremental phase deviation between symbols is the main influencing factor in the tracking phase, and its cumulative effect will cause a large phase rotation of symbols with larger sequence numbers in a frame, resulting in wrong judgments

Images