Two-dimensional beam-scanning linear active leaky-wave antenna array using coupled VCOs

Abstract

An active phased-array design for electronic two-dimensional beam scanning using a phase-shifterless linear one-dimensional active leaky-wave antenna array is demonstrated. The varactor-tuned voltage-controlled oscillators (VCOs) and coupling network are implemented in this array. Three coupling networks are designed and compared for optimum coupling strength between each VCO element. The measured pattern of a 4 x 1 active leaky-wave antenna array shows that the main beam can be continuously scanned from 68 degrees to 40 degrees in elevation, as the frequency varies from 8.24GHz to 9.15GHz. This is equivalent to over 10% electronic tuning bandwidth. By tuning the free-running frequencies of the end elements, the main beam can be continuously scanned from -26 degrees to +10 degrees from broadside with azimuth symmetry in a conical scan manner.