Beamforming in quasi-optic active arrays using subharmonic locking

Locked oscillator patch antennas can be used in quasi-optic arrays for millimetric applications. Beam control in such self locked arrays is difficult as the basic array mode produces a broadside array. We report here on a subharmonic locking technique that gives improved element phase control over fundamental locking methods. However there are some associated limitations which will influence the implementation and these are discussed