The current paper characterises the performance of the three radio frequency channels, orthogonal frequency division multiplexed (OFDM) radio-over-fiber (RoF) transmission system in terms of error vector magnitude and received optical signal power for a typical 10 GHz receiver obtained by the comprehensive simulations. The impact of the signal-to-noise ratio (SNR) of the OFDM channels transmitted is also considered. We demonstrate that the SNR decrease from 40 dB to 25 dB results in an error vector magnitude (EVM) increase of up to 4 %. Furthermore, we propose the approach to allow one to adjust these results to other receiver sensitivity and responsivity values by introducing a delta in received optical signal power, eliminating additional simulation or complicated calculations. The feasibility of adjustments with a precision of up to 0.001 % of the EVM is proved.