Systems and methods for reducing adjacent channel leakage ratio

Abstract

An analog radio over fiber (AROF) wavelength division multiplexing (WDM) system and method for reducing adjacent channel leakage ratio (ACLR) in a radio frequency signal provided by an AROF WDM system are provided. The AROF WDM system comprises a plurality of transmitters, a multiplexer, a demultiplexer, a plurality of receivers and a controller. Each transmitter is for receiving a radio frequency input signal and for modulating the radio frequency input signal onto an optical signal to obtain a modulated optical signal. The multiplexer is for receiving each modulated optical signal from the plurality of transmitters and for combining the modulated optical signals into a combined optical signal to be sent a distance over an optical fiber. The multiplexer has a pluralities of passbands with each passband having a center wavelength. The demultiplexer is for receiving the combined optical signal and for separating the combined optical signal back into the individual modulated optical signals. Each receiver is for receiving one of the modulated optical signals from the demultiplexer and for converting the received modulated optical signal into a radio frequency output signal. The controller is configured to detune, for each transmitter, one of that transmitter and the multiplexer relative to the other such that a wavelength of the modulated optical signal transmitted by that transmitter is longer than the center wavelength of a corresponding one of the plurality of passbands of the multiplexer.