| 摘要 |
A channel estimator for varying IIR(Infinite Impulse Response) filter coefficients according to the moving speed of a mobile terminal and a method thereof are provided to prevent deterioration in performance by selecting and setting optimized IIR filter coefficients according to the movement speed of a mobile terminal. A channel estimator comprises an I/D(Integration and Dump) part(100), a coefficient change part(200), and the first IIR filter(102). The I/D part(100) receives spread I and Q signals, and sums up the spread values of each of the inputted I and Q signals. The coefficient change part(200) receives the I and Q signals outputted from the I/D part(100), selects one among preset coefficient pairs in regular sequence, executes IIR filtering using each selected coefficient pair, and outputs a channel estimation result value based on each selected coefficient pair. The coefficient change part(200) compares the channel estimation result values with a channel estimation value for the case no noise is generated. Then, among the differences between the channel estimation result values and the channel estimation value, the coefficient change part(200) selects a coefficient pair based on the smallest difference as an optimized coefficient value and outputs it. The first IIR filter(102) receives the I and Q signals and the optimized coefficient value, executes IIR filtering according to the optimized coefficient value, and outputs the channel estimation values of the I and Q signals. |
