Frequency offset estimation method and frequency offset estimation device

Abstract

Embodiments of the invention disclose a frequency offset estimation method and a frequency offset estimation device. The method comprises the following steps: carrying out frequency offset estimation according to the repeatability of cyclic prefix CP to get a first frequency offset estimated value; getting at least one second frequency offset estimated value through a preset pilot pair, and getting a wide range of frequency offset estimated values to be chosen according to the at least one second frequency offset estimated value and preset operation rules; and getting an optimal frequency offset estimated value according to the first frequency offset estimated value, the wide range of frequency offset estimated values to be chosen and a preset range value.

Description

technical field [0001] The invention relates to communication signal processing technology, in particular to a method and device for frequency offset estimation. Background technique [0002] Orthogonal Frequency Division Multiplexing (OFDM, Orthogonal Frequency Division Multiplexing) technology is a multi-carrier transmission technology in which sub-carriers are orthogonal to each other. This technology requires that sub-carriers are orthogonal to each other and is very sensitive to carrier frequency offset; so , the problem of carrier frequency offset has become one of the core problems of current OFDM technology. [0003] At present, for the problem of small frequency offset, there are many high-precision and simple methods; but for the problem of large frequency offset, two solutions are usually used: [0004] The first method uses the repeatability of a cyclic prefix (CP, Cyclic Prefix) to estimate the frequency offset, but the method of using the CP to estimate the fr...

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Problems solved by technology

[0004] The first one uses the repeatability of the cyclic prefix (CP, Cyclic Prefix) to estimate the frequency offset, but the method of using the CP to estimate the frequency offset is not accurate enough, and the maximum error can reach several kilohertz

[0005] The second method uses two cell-specific reference signal (CRS, Cell-specific Reference Signals) pilot symbols in the frequency domain to perform frequency offset estimation, but the frequency offset estimation range of this method is not large enough, for example, according to a CRS conventional symbol pair ( 0, 7) or (4, 11) the range of frequency deviation is (-1000, 1000) Hz, when the real frequency deviation value exceeds this range, it is necessary to continuously add or subtract 2000 Hz to the real frequency deviation value until the result range It is in the range of (-1000, 1000) Hz, so there will be a wide range of frequency offset values ​​that may be 1000Hz, and the phenomenon of frequency offset flipping occurs through the calculation of 1000-2000=-1000Hz

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