A method and electronic article surveillance ("EAS") system reduce interference. The EAS system includes a detection zone. At least one reference pattern of transmission windows for an interfering EAS system is provided. The reference pattern indicates a sequence of time slots for which the interfering EAS system is transmitting. A sample pattern of signals is received. Each signal has a corresponding amplitude. The received sample pattern is compared to the at least one reference pattern. Responsive to determining that the received sample pattern matches the at least one reference pattern, the at least one reference pattern is used to trim samples received during receive windows corresponding to the time slots for which the interfering EAS system is transmitting.