Control of the main beam of a half-width microstrip leaky-wave antenna by edge loading using the Transverse Resonance Method

As the need to conserve fuel is ever increasing, developing low-profile, lightweight, broadband antennas is undoubtedly important to the success of the United States Air Force. The Half-Width Microstrip Leaky-Wave Antenna (HMLWA) addresses these important issues along with other beneficial characteristics such as being inexpensive and conformable (say to the fuselage of an aircraft) all while being half the width of its full-width counterpart, the Full-Width Microstrip Leaky-Wave Antenna (FMLWA).;It is well known that the main beam angle of a leaky-wave antenna scans with frequency [1] and that the angle can be controlled by reactively loading the radiating edge [2]-[7]. This work will optimize the reactive loading (lumped capacitors) of a current HMLWA antenna design allowing for fixed-frequency beam steering over the operational frequency range. The Transverse Resonance Method (TRM) is used to analyze the HMLWA antenna for various edge loading configurations. Full-width and half-width antennas are simulated on both finite and infinite ground planes in an attempt to verify the claim that the HMLWA antenna reasonably approximates its full-width counterpart. Furthermore, the radiation pattern of the HMLWA antenna is determined analytically using the Radiating Aperture Method (RAM) and compared to the patterns of simulated antennas. Finally, the proposed antenna is fabricated and measured, and the results are presented.