Electromagnetic Modelling of a 2D Transmit Array for Polar Over-the-Horizon Radar

The paper highlights results from an electromagnetic modelling study into the properties of a two-dimensional transmitter array proposed by Riddolls for over-the-horizon radar in the polar region. The modelling indicates that the total radiated power efficiency of the array is low and total radiated power is likely to be insufficient for target detection and tracking in an operational OTHR. Overall radiated power efficiency is at least 10dB less than established OTHR transmitter systems. The limited array size and the need for extreme steer from the array normal mean that there is little capacity to steer the array beams in elevation, so the array design is likely to be ineffective for clutter mitigation using elevation spatial selectivity or nulling.