| 摘要 |
PROBLEM TO BE SOLVED: To correctly seek an ensemble band. SOLUTION: When seeking is instructed, a system controller 38A sequentially tunes a front end 2 to a plurality of ensemble frequencies. When a NULL detection circuit 13 detects a NULL symbol at a received frequency, a frequency error detection circuit 33A decodes a carrier-wise component of a valid symbol (PRS), to discriminate whether or not the maximum value of a correlation function calculated based on a prescribed reference code is a prescribed value or higher. The controller 38A stops seeking when the maximum value is the prescribed value or over, and outputs frequency error data, which is detected by the frequency error detection circuit 33A, to an integration circuit 34. The frequency error data are integrated by the integration circuit 34, and applied to a reference oscillator 6 of the front end 2 as a control voltage for adjusting the tuning frequency automatically. If the maximum value of the correlation function calculated by the frequency error detection circuit 33A is not the prescribed value or higher, seek control is continued. |
