Frequency offset and phase offset estimation method in single carrier interleaved frequency division multiple access (SC-IFDMA) system

Abstract

The invention discloses a frequency offset and phase offset estimation method in a single carrier interleaved frequency division multiple access (SC-IFDMA) system and mainly solves the problem that inthe prior art, the estimation precision is low under an environment with relatively poor channels. The method comprises the application steps of generating transmitting data; arriving at a receivingend by the transmitting data through the channels; extracting data of each single carrier interleaved frequency division multiple access symbol of the receiving end; carrying out frequency offset estimation through utilization of repeated data and through adoption of an iteration method; carrying out frequency offset correction on received data through estimated frequency offset; demapping frequency offset corrected signals through subcarriers to obtain transform domain data; ordering the transform domain data according to an ordering rule and extracting phases of the first K pieces of data; calculating difference values of the phases of the K pieces of data and initial phases of symbols of quadrants in which the data is located; and averaging the obtained K difference values to obtain a final phase offset estimation value. According to the method, the estimation precision is high, the frequency offset and phase offset can be effectively estimated, and the method can be used for correcting rotation of a signal constellation diagram in the single carrier interleaved frequency division multiple access system.

Description

technical field [0001] The invention belongs to the field of communication technology, in particular to an estimation method of frequency offset and phase offset, which can be used to correct single-carrier interleaved frequency division multiple access systems in ionospheric or tropospheric scatter channels, non-visible wireless channels and satellite channels The rotation of the signal constellation diagram in . Background technique [0002] The most representative types of scatter communication are tropospheric scatter communication and ionospheric scatter communication. Troposcatter communication uses the inhomogeneous characteristics of the tropospheric atmospheric medium to cause radio wave scattering to achieve trans-horizon information transmission. Compared with line-of-sight transmission, the biggest advantage of tropospheric communication is the long-distance frequency modulation communication with a distance of 100-500km. However, in the channel environment wit...

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Problems solved by technology

The disadvantage of this method is that the process of phase offset estimation uses nonlinear transformation, and the nonlinear transformation is related to the size of the signal-to-noise ratio. The nonlinear transformation performed under different signal-to-noise ratios is different, which leads to the complexity of phase offset estimation. high degree

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