UHF SATCOM Wideband Interference Mitigation

SATCOM is a critical component of the C4ISR infrastructure that allows commanders to control the battlespace. While the UHF band offers many advantages, it is prone to narrowband and wideband interference. It is critical to eliminate large signal saturation and ADC device overload prior to any digital signal processing. This is particularly important for shipboard receivers, which often operate in the presence of powerful co-site interference. Robust signal processing is also necessary to extract the desired signals in the presence of large interference. Two primary processing approaches are proposed: time-frequency grid excision suitable for wideband processing, and an adaptive filtering technique that exploits temporal and/or spatial diversity of the interference. RAS proposes a multi-pronged interference mitigation concept utilizing interference suppression at RF to prevent receiver saturation followed by additional interference rejection through digital signal processing in the time and frequency domain. Interference avoidance techniques including RF channel selection, spectral RF filtering, time-domain blanking, and sidelobe-blanking are all unsatisfactory. An all-digital solution to the RF interference rejection is not practical with current receiver technology when the required instantaneous dynamic range becomes excessive. The combined approach provides the ability to detect low-level SATCOM signals in the presence of interference