PHASE DETECTION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a phase detection device which has high accuracy with no dependence on the stability of an element and also to reduce the work load in a test adjustment mode by correcting the phase variance of the element in the sampling timing of an A/D converter. SOLUTION: An input IF signal is divided into two signals and multiplied by the coherent signals, having phases different from each other by 90 deg.. These multiplied signals are filtered, undergo A/D conversion via the A/D converters 12A and 12B, and are outputted as digital signals Ich and Qch. On the other hand, the DC component of the clock signal of a terminal 6 is eliminated by a low-band cut-off filter 7. Then the signal of the terminal 6 is converted into a linearly integrated waveform, which is compared with the threshold voltage that underwent A/D conversion according to the delay data of Ich and Qch, set at the terminals 9A and 9B via the compactors 11A and 11B respectively. Then the digital signals obtained through the comparison are outputted to the converters 12A and 12B as the sampling clocks. The difference in leading edge of both sampling clocks is used for correcting the phase shift. Thus, the phase is easily detected with high accuracy.