Interference cancellation system

This thesis examines the problem of coupling of on-channel repeaters in a 3G wireless system. Unwanted feedback occurs between the donor and coverage antennas of a repeater. The unwanted feedback appears as radio echoes which creates interference in the incoming signal from the base station. The thesis describes an adaptive method to suppress these radio echoes. The proposed interference cancellation system (ICS) can detect and cancel the radio echoes from either direct coupling or reflections from buildings around the repeater. A novel multiple-tap radio echo suppressor (RES) is developed and fabricated on the Xilinx Virtex-4 FPGA platform.