Mutual coupling of antennas in a meteor radar interferometer

Meteor radars have become common and important tools in the study of the climate and dynamics of the mesosphere/lower thermosphere (MLT) region. These systems depend on accurate angle-of-arrival measurements to locate the positions of meteor trails in the atmosphere. Mutual coupling between antennas, although small, produces a measurable error in the antenna pair phase differences used to deduce the angle of arrival of incident radiation. Measurements of the scattering parameter matrix for antennas in an interferometric meteor radar array have been made and applied to the existing angle-of-arrival calculation algorithm. The results indicate that mutual coupling of antennas in the array produces errors in the zenith angle estimate of less than ± 0.5°. This error is primarily in the form of a gradient across the field of view of the radar, which can be removed using existing phase calibration methods. The remaining error is small but will produce small systematic variations in the height estimates for detected meteors. 

Key Points:

Mutual coupling in meteor radar is small, but non-negligible.

Antenna mutual coupling can be easily measured.

Antenna mutual coupling can be corrected for.