Abstract: In a wireless security system having a plurality of RF sensor/transmitters and a system controller, jamming signals are detected by comparing a near-term noise value with the expected signal strength of transmissions from the RF sensor/transmitters minus a detection threshold, and with the sum of a long-term noise value and a jamming threshold. In addition, the trend of the long-term noise value is analyzed to determine whether a jamming signal is being intentionally and gradually introduced into the security system environment. The system controller may include a plurality of antennas. Jamming may be detected for each antenna or for all of the antennas, collectively.