140-GHz

In this paper, a TE-{340} -mode substrate-integrated cavity (SIC) excited 2times2 slot antenna subarray with two TE-{210} -mode SICs' loading is presented at 140 GHz in low-temperature co-fired ceramic. By using the TE-{340} -mode SIC, the number of vias used in the feeding network and the area of the feeding network can be reduced compared to the feeding network composed of conventional TE-{10}/TE-{20} -mode SIW power dividers. The proposed simplified and miniaturized high-order mode SIC-based feeding network leads to lower transmission loss and fabrication cost and reduces the fabrication difficulty. Each pair of radiating slots is loaded by a TE-{210} -mode SIC to improve the impedance bandwidth and the gain performance. For the proof of concept, an 8times8 antenna array is further designed and measured. The measured impedance bandwidth of the proposed 8times8 antenna array is 10.7% from 130.3 to 145 GHz for |S-{11}|leq -10 dB. The measured peak gain is 20.5 dBi. The measured radiation efficiency is 59.2%. © 2013 IEEE.