Radiation characteristics of active frequency-scanning leaky-mode antenna arrays

Active frequency-tuning beam-scanning leaky-mode antenna arrays have been d emonstrated in this paper. These antennas integrated one or several microst rip leaky-wave antenna elements with a single varactor-tuned HEMT VCO as an active source. Noted that the measured scan angles of the 1x1 and 1x4 ante nnas were approximately 24 degrees and the scanning range of the 1x2 antenn a was 20 degrees. Furthermore, reflected wave due to the open end of each l eaky-wave antenna element has been suppressed by the symmetric configuratio n of this antenna array and the antenna efficiency increases. When comparin g with the measured radiation pattern of the single element antenna, we fou nd that the 1x2 and 1x4 antenna arrays can effectively suppress the reflect ed power by more than 5.5 dB and 10.5 dB, respectively, at 10.2 GHz. The po wer gain are more than 2 dB and 3.16 dB higher than the single element ante nna with a measured EIRP of 18.67 dBm.