Reduction of cosite interference for digital FM frequency hopping radios

Digital FM frequency hopping radios closely located together on a platform or on nearby platforms may cause interference to each other. In this paper, the interference effects of cosited radios will be discussed. These effects include transmitter wideband noise, transmitter intermodulation and receiver intermodulation. The performance of the radio will be considered taking into account the interference from intermodulation products and multiple users. Potential solutions to reduce the interference from cosited radios will also be discussed. These solutions include the use of filters, orthogonal hopping, and coupling all cosited radios through a highly linear amplifier. Ways to achieve higher isolation between radios will also be discussed.