Wideband IF time delay steering of array antennas

It is shown that when IF time delays are used to steer the main beam of an array antenna an additional incremental phase shift must be introduced into the local oscillator of each mixer to produce in-phase summation of each element signal. The delay provides alignment of the envelopes while the local oscillator phase shift provides in-phase summation. This condition is found to be independent of frequency and thus bandwidth.