How can intermodulation interference between two transmitters in close proximity often be reduced or eliminated?

Intermodulation interference occurs when two or more signals mix together, creating additional unwanted signals that can disrupt communications. One effective method to mitigate this type of interference is by utilizing a terminated circulator or ferrite isolator in the feed line.

These devices are designed to allow signals to pass in one direction while preventing signals from returning to the transmitter. As the transmitted signals pass through the isolator or circulator, any reflections or unwanted signals are absorbed or redirected, reducing the potential for intermodulation products that can interfere with other systems. This separation of paths helps minimize interference by ensuring that the signals from one transmitter do not affect the operation of another, even when they are physically close together.

While moving the transmitters further apart can also reduce interference by increasing the distance between signal pathways, the use of circulators and isolators offers a more immediate and effective solution in circumstances where space is limited. Using separate frequencies is another approach, but it may not always be feasible depending on operational needs or frequency allocations. Increasing the power output of both transmitters could actually exacerbate interference issues rather than alleviate them. Therefore, installing a terminated circulator or ferrite isolator effectively addresses intermodulation interference in a controlled manner.