Oversampling of OFDM post-IFFT frame

Question

I would like to build IQ radio waveform - first part - synchronisation sequence (ZC) and second part, OFDM frame with Cyclic Prefix(after IFFT). I want to to oversample ZC sequence at transmitter, and filter it with RC filter - in order to limit it's spectral bandwidth, and to make burst detection easier at receiver(using matched filtering). The only thing that is puzzling me, is the fact that I also have to oversample(and filter) also OFDM frame Then how should I oversample, and apply filtering to OFDM signal to not distort it(and it's CP)?