Antenna systems for ESM applications¿a land-mobile example

The design of antenna systems for ESM applications requires that a number of demanding requirements be met simultaneously, each of them imposing constraints on the possible solutions that may be adopted. The paper uses the design of a land-mobile system employing a quad-ridged horn to illustrate briefly the various constraints and the solutions that can be adopted, indicating how the requirements of, for example, aviation systems may differ. The effect on the overall design of having to meet requirements for DF capability and polarisation detection, in addition to those for ESM performance and, possibly, having to at the same time produce an antenna system suitable for high-power transmission or simultaneous transmission and reception, is also discussed.