RF Cosite Interference

Interference between RF devices is one of the biggest challenges in designing and maintaining commercial and defense systems. These systems include ships, airplanes, drones, cell phones, satellites, automobiles and generally, anything that has RF systems installed in or on it. The problem is complex for a number of reasons including the broadband nature of the interference, the lack of detailed performance data, introduction of intermodulation products when multiple systems interact with one another and a host of other reasons. Identifying and solving cosite interference issues early in a design is critical as discovering an interference problem right before bringing a product to market or after it has been put into service can cost millions of dollars to fix the problem and lost revenue. One only has to perform a web search for “cosite interference” to see a sample of the issues that have plagued military and commercial programs for decades.

Cosite interference occurs when one or more source signals cause a victim system to not function properly. Interference can vary from non-critical annoyances to critical safety of flight issues that can result in costly last-minute fixes or in extreme scenarios, loss of life. It is essential to perform cosite analysis early in the design phase of a program to identify and mitigate issues before they become reality. EMA utilizes an advanced software framework for managing RF system performance data, simulating cosite interference and mitigating RFI issues. The analysis accounts for all of the RF systems on the platform and all of the possible channels that those RF systems operate over. It is important to consider both in-band and out-of-band interference when analyzing cosite interference taking into account transmitter harmonics and spurious emissions as well as receiver mixer products and spurious responses. Further, when multiple RF systems are operating simultaneously, one must account for intermodulation products produced by nonlinear devices such as amplifiers.

EMA performs all antenna-to-antenna coupling analyses for all antenna pairs. EMA can also compute installed antenna performance to consider any obscuration or other effects that may degrade performance.