Design and Measurement of a 2x2 Array of Coaxial Periodic Leaky-Wave Antennas

A 2x2 array of coaxial periodic leaky-wave antennas at X-band has been designed, fabricated and measured. It achieved a gain of more than 10 dBi at 9.8 GHz, input return loss better than 10 dB from 8 GHz to 12 GHz (other than the broadside frequency) and a 3 dB beamwidth of 9 degrees. The sidelobe level is better than 10 dB from 8 GHz to 10.5 GHz. The antenna also achieved a reduced open stopband attenuation at 9.8 GHz. A beam scanning range of 35 degrees from backward to forward direction over a 4 GHz span was achieved. Good agreement between the simulated and measured results was obtained.