Towards a 3:1 band phased array

A multielement phased array antenna has been developed to demonstrate the feasibility of broadband operation. Quadridged waveguide horns were employed as antenna elements to achieve wide bandwidth and polarisation diversity. The elements were arranged into two offset linear arrays to reduce inter-element spacing at the higher operating frequencies. A feed network has also been constructed employing MDS custom designed GaAs MMICs for both the switches and phase shifters. Phase alignment of the antenna array and feed network has been successfully completed for linear polarisations. Once aligned the system has demonstrated reasonable scanning performance for both vertical and horizontal polarisations. The gain of the antenna array and feed network has also been measured. At fo the measured values gave close agreement with predicted results