Orthogonal frequency division multiplexing has been regarded as one of the promising technologies for the optical access systems application. However, high peak-to-average power ratio will cause the signal distortion and enable the used amplifier to operate in nonlinear section.
In this paper, a modified selected mapping technique is introduced for reducing the peak-to-average power ratio and enhancing reception performance of the downstream 8QAM-OFDM signals in optical access systems.
Compared with the traditional selected mapping technique, the PAPR value of 8QAM-OFDM optical downstream signals with 128 subcarriers is reduced by almost 2 dB using modified SLM when the complementary cumulative distribution function probability value is 10−2. Moreover, the bit error rate performance will be improved, while 10Gbit/s 8QAM-OFDM optical downlink signals are transmitted over single mode fiber with different access length.
Hence, the proposed scheme becomes more efficient for the future optical orthogonal frequency division multiplexing access systems.