Patent ID: 6987794

Claim:
A receiver that receives transmission signals transmitted in a communication system using plural frequency channels, comprising: a phase locked loop (PLL) having an output signal being formed of differential information output means for frequency dividing an input signal in a predetermined frequency division ratio to obtain a frequency-divided signal and for outputting differential information between said frequency-divided signal and a clock pulse, filter means for outputting a differential signal voltage corresponding to said differential information, and a voltage-controlled oscillator for controlling a frequency of said output signal according to said differential signal voltage; receiver means for receiving a transmission signal having as a transmission frequency the frequency of the output signal output from said PLL; estimation means for estimating a receiving channel corresponding to the transmission frequency of said transmission signal; and control means for controllably sampling a plurality of times the frequency of said output signal of said PLL from a receiving channel at one frequency to a receiving channel at another frequency when the frequency of the output signal from said PLL is set to a frequency of the receiving channel corresponding to the transmission frequency of said transmission signal, wherein said estimation means estimates the receiving channel corresponding to the transmission frequency for said transmission signal based on a received signal received by said receiver means, in the period during which said PLL samples from the receiving channel at one frequency to the receiving channel at another frequency, and wherein said estimation means comprises: a signal strength measuring circuit for measuring the signal strength of said received signal; and an estimation circuit for estimating the signal strength measured in said signal strength measuring circuit and the receiving channel corresponding to the transmission frequency of said transmission signal based on a hopping pattern in said receiver.