An edge-slotted waveguide array with dual-plane monopulse

Edge-slotted row waveguides have often been stacked to form light-weight planar arrays. With phase-shifter scanning in elevation and 360/spl deg/ mechanical rotation in azimuth, a large surveillance volume may be covered at relatively low cost. For applications that require accurate target location, elevation monopulse is readily available by means of an appropriate beamformer. However, past attempts to obtain monopulse in the plane of the slotted waveguides have not met with much success. While the alternative has been to employ run length estimation (beam-splitting based on a sequence of target returns), accuracy limitations and the required elevation dwell time render this solution inadequate for certain applications. Now, however, a new waveguide array configuration has been developed that provides dual-plane monopulse and still retains one-dimensional phase scanning along with the advantages of low cost and light weight. A full-scale Ku-band array employing this new architecture has been built and tested to demonstrate practical utility.