The biggest limitation of Radio over Fiber (ROF) links in a wireless network is its limited dynamic range due to ‘Non Linear Distortions’ (NLD). In this paper a higher order adaptive filter based modeling and predistortion scheme is proposed to compensate this NLD. The filter is adapted from the distortions of vectormodulated symbols, so that no in-depth knowledge of physical link parameters is needed. Experimental and simulation results show that a third order filter accurately models the ROF link while a second order filter adequately compensates for the phase nonlinearity. The power handling capability of the laser diode is the upper limit in this approach. Key Words Nonlinear distortion, Adaptive Filters, Communication system nonlinearities, Optical fiber communications, Indoor radio communications and Compensation.
Xavier N. Fernando, Abu B. Sesay