| 摘要 |
PROBLEM TO BE SOLVED: To estimate the frequency accurately in a short time under a strong distortion and interference wireless environment by using an AFC device of a cellular telephone set to detect a frequency correction burst and using an AR parameter estimate device to estimate the frequency according to a prescribed equation. SOLUTION: An AFC device of a cellular telephone set receives, detects and buffers a frequency correction burst 112 of a broadcast signal. Then a BFP 104 is used to apply filter processing to the burst to exclude an out-band noise and interference and a uni-pole AR filter 108 applies filter processing to the signal and its output 110 is estimated by a parameter estimate device 112 according to a prescribed equation. The processing of filtering by the AR filter 108 to the estimate output 114 is repeated for plural number of times, a frequency calculation device 116 calculates the estimate values and the two optimum estimate values are averaged by a frequency estimate value averaging device 120 to obtain a final estimate value 122. Thus, the frequency is estimated accurately in a short time against Gaussian noise, channel interference and channel fading. |
