Patent ID: 8306132

Claim:
A detection apparatus that detects a phase alignment error between transmission signals transmitted on different channels, comprising: a correlation calculating section that calculates a cross-spectrum between the transmission signals based on a result of a measurement of the transmission signals transmitted in the channels, wherein the transmission signals have substantially the same spectrum at a prescribed overlapping frequency band, and are input respectively to the channels, and the correlation calculating section calculates the cross-spectrum between the transmission signals in the prescribed overlapping frequency band; a phase difference calculating section that calculates a phase difference spectrum between the transmission signals based on the cross-spectrum calculated by the correlation calculating section; and a detecting section that detects a difference between transmission times of the transmission signals transmitted on the different channels and a phase offset between the transmission signals, based on the phase difference spectrum calculated by the phase difference calculating section and comprising: a time difference calculating section that calculates the transmission time difference based on a slope of the phase difference spectrum; and a phase calculating section that calculates the phase offset based on an intercept of the phase difference spectrum.