CALIBRATION OF PLURAL - CHANNEL SYSTEM

Abstract

In a system having plural signal-carrying channels, a phase shift is introduced between a signal in one of the channels and a reference signal for calibrating the individual channels. The reference signal is obtained by adding samples of signals in other ones of the channels. The phase shift is introduced by phase-shift apparatus responsive to a command signal directing a continuous monotonic increment of phase. The phase incrementing introduces a frequency shift (a serrodyne), which produces a beat-frequency signal for mixing a channel signal with the reference signal. The beat-frequency signal is phase locked to a modulation patern of a command signal, whereby a measurement of phase (or delay) can be made between the two signals for calibration of each channel within the system. Separate calibrations may be made for different presumed values of system delay so as to obtain a value of system delay which causes the calibration sequence to converge to fixed values of phase shift introduced in each of the channels.

Source: Google Patents

35 USC §181 Secrecy Order

Inventor

• 1A. R. LOPEZ