PHASE DETECTING CIRCUIT

PURPOSE: To make mobile devices for mobile body communication minituarized, lightweight, economical and low in power consumption by elucidating the configurating method of a phase detecting circuit through the use of Σ-Δ modulating technique where the non-linearity of phase detection is eliminated so as to obtain the phase detection circuit with sufficient detection performance without requiring large capacitance ROM, a subtracter and, moreover, ADC. CONSTITUTION: A first phase information detecting part 10 outputs a first coarse phase value S1b and a first minute phase value S1a from the I and Q components of an inputted plural-element baseband signal. The second phase information detecting part 20 outputs the second coarse phase value S2b and the second minute phase value S2a by plural phase areas which are π/N shifted as against the plural divided phase areas of the first phase information detecting part 10. Then, a phase synthesizing part 30 adds the respective coarse phase values to the minute phase values, averages the added result and outputs a detection phase value obtained by cancelling phase difference by the addition output of the respective coarse phase values and the minute phase values.