Patent ID: 6625434
Filing Date: 2003-09-23
Classification: H03J,H04B

Abstract:
A method of performing an automatic frequency control process in a mobile station to equalize the frequency of a reference frequency signal for use in demodulating a signal received from a base station with the frequency of a reference frequency signal in the base station, said mobile station comprising:an antenna; a radio frequency (RF) unit; a mixer; a reference oscillator; an analog to digital (A/D) converter; a plurality of finger receivers having correlators and respective interpolating synchronous detectors; an automatic frequency control (AFC) circuit; and a rake mixer; said mixer frequency-converting an RF signal from said antenna into a chip rate signal, the chip rate signal being converted into a digital signal by said A/D converter, the digital signal being supplied to said plurality of finger receivers for despreading by said respective correlators to demodulate a data channel (DTCH), said respective interpolating synchronous detectors removing fading from the DTCH, said rake mixer combining the digital signals at a maximum ratio and outputting the combined digital signal; said method comprising the step of: carrying out said automatic frequency control process in a speech communication mode in which the data channel (DTCH) transmitted from the base station is being received.