A New Electronic Phase Shifter (Correspondence)

With the imminent feasibility of very large electronically-scanned phased-array antennas, has come the necessity for suitable circuitry for accurately shifting phase of very many elements. A scheme, which is now receiving some attention, was described by the author in February, 1960, in a Mitre memo, which has achieved some circulation in Air Force circles. The basic idea is simple, taking advantage of the fact that the phase of the harmonic of a fundamental frequency is proportional to the harmonic number, viz., sin nω(t + τ) = sin (nωt + nωτ) = sin (nωt+ψ) where ψ= nωτ.