| 摘要 |
PURPOSE:To prevent occurrence of overflow or underflow of a control variable and to improve the reliability of a phase controller by providing a means detecting a phase control variable by a phase control system and keeping the control variable to a prescribed range. CONSTITUTION:A phase control variable psii being an output of a VCO 123 is fed to a phase control variable detector 130, and whether or not the phase is within a predetermined phase of (-pi)rad<=psii<=pirad is checked and the result is fed to a phase quantity converter 131. Depending whether overflow is detected at psii>=pirad or underflow is detected at psii<=-pirad, the conversion of whether 2pirad is subtracted from the psii or added thereto is applied to the psiia and the result of psiia=psii is outputted in case of within the range. Then the psii is limited within the range. The psiia is sent to a phase rotation calculation section 132, where the calculation of psiia e<-jpsii> is applied to obtain a phase correction control variable and the input signal to a decider 115 is corrected. |
