Radio-over-fiber (RoF) systems operating at millimeter wave frequencies have trigged great interest in developing future wireless-access networks. They are expected to offer wider service coverage, broader bandwidth service, and larger channel capacity. In the typical architecture of RoF network, the radio frequency (RF) signals are generated at the central station and are distributed to and from the radio base stations as millimeter wave modulated optical signals to overcome the high propagation losses associated with wireless communications at these frequencies. This thesis addresses the effect of optical crosstalk on the bit error rate (BER) performance of RoF network incorporating both wavelength division multiplexing (WDM) and frequency reuse techniques. Four types of crosstalks are considered here: homodyne, heterodyne, co-channel, and adjacent-channel. These types occur, respectively, when the optical frequencies and the RF frequencies of the desired and crosstalk signals are equal or not. Analytical expressions are derived to characterize both desired and crosstalk signals. The results are used to investigate the key role played by both optical phase shift Dq and RF phase shift Df on determining the BER performance of RoF operating in the presence of various types of crosstalk. The results indicate clearly that the effect of the adjacent channel heterodyne crosstalk can be cancelled perfectly if suitable filtering scheme is used at the post detection stage.