51results about How to "Expand the range of frequency offset estimation" patented technology

The present invention provides a frequency offset estimation method and system for a narrowband physical uplink shared channel of a wireless comprehensive tester. The frequency offset estimation method includes the following steps: step S1, using a narrowband demodulation reference signal to perform frequency offset estimation; step S2, obtaining The initial maximum frequency offset value; step S3, calculate the phase value of the time domain data of the local narrowband demodulation reference signal; step S4, carry out frequency offset compensation to the time domain signal of the received narrowband demodulation reference signal, and calculate the frequency The phase value of the time-domain data of the narrowband demodulation reference signal after offset compensation; step S5, calculate the phase difference between the received narrowband demodulation reference signal and the local narrowband demodulation reference signal; step S6, calculate the phase difference Its variance; Step S7, calculate the final estimated value of frequency offset by the minimum variance value of the variance. The invention enables the wireless comprehensive tester to greatly expand the range of frequency offset estimation on the basis of ensuring the accuracy of frequency offset estimation.

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.