In this work, a radio over fibre link with improved receiver sensitivity was reported. The basical mechanism of this prototype was to realize optical single sideband modulation with an optimum optical carrier-to-sideband ratio(OCSR). To do this, both polarization modulation and optical interleaving technology were employed. The linearly polarized incident light was firstly oriented at an angle of α(α≠0° or 90°) relative to one principal axis of the polarization modulator(PolM), which is biased by Vπ and driven by RF signals. Then a polarizer with its polarization direction β(β≠0° or 90°) relative to one principal axis of the PolM was used to linearize the polarization state. Finally, optical double sideband signal was converted to optical single sideband signal by using a standard optical interleaver. It is found the OCSR is only dependent on the values of two polarization angle, α and β. With careful adjustment, the OCSR can be reduced to 0 dB, which is the optimum value for a single RF tone modulation. The receiver sensitivity of the fibre link is analyzed by theory and then verified by simulation. It can be greatly improved by using this technique.