Broadband active microstrip array elements

The design is presented of active microstrip array elements by the combination of active devices with radiating patches to obtain broad bandwidth and extra power gain. The design is illustrated with an active microstrip transmit antenna in a two sided structure. In terms of the realised gain with a flatness of +or-0.45 dB, a bandwidth of 24% of the centre frequency was achieved. The results are very attractive for broadband MIC active array design.