The broadband access networks require suitable differential modulation techniques that can provide better performance in real-time fading channels. A heterogeneous optical access network adopting spectrally efficient DAPSK – Orthogonal Frequency Division Multiple (OFDMA) - Passive Optical Network (PON) is proposed and simulated. The performance of the proposed heterogeneous network is analyzed in terms of received Bit Error Rate (BER) and spectral efficiency. The results show that 64 DAPSK – OFDMA over the proposed architecture achieves a better spectral efficiency of about 1.062 bps/Hz than 64 QAM – OFDMA with less degradation in error performance.