VHF cosite interference challenges and solutions for the United States Marine Corps' expeditionary fighting vehicle program

The United States Marine Corps' expeditionary fighting vehicle (EFV), currently under development, is a modern, highly manoeuvrable, tactical, network-centric vehicle. With its numerous communications systems, the EFV presents a considerable challenge to radio-frequency (RF) engineering designers situating antennas on the vehicle. This paper concentrates on the most severe interference problem - VHF cosite interference - presenting a brief description of the EFVs communications architecture and the rationale adopted for antenna placement. The problems presented by an installation of this complexity are analyzed and potential solutions are presented and compared. Specific technical problems related to the operational use of interference-cancellation systems are also presented and a number of general lessons learned are highlighted.