The accuracy of multilateration systems can be greatly improved by using a correction method based on the SLS (Sideband Lobe Suppression) signal produced by a Secondary Surveillance Radar (SSR). Multilateration is a cooperative surveillance technique for aircraft equipped with Air Traffic Control Radar Beacon System (ATCRBS), Mode S, or Automatic Dependent Surveillance Broadcast (ADS-B) transponders. When one of these transponders aboard a vehicle is interrogated, it responds by broadcasting a message based on what the interrogation requests. These reply messages may be multilaterated to determine the source position of the transmission. Multilateration is a Time Difference of Arrival (TDOA) technique similar to triangulation. Multilateration can be performed to locate the transmission source of any SSR signal. Error detection and correction may be performed on the system by conducting a comparison of a known TDOA for the receiver/transmitter geometry, to the measured TDOA from a Side Lobe Suppression (SLS) pulse emanating from a primary radar.