Framework for optical millimetre-wave generation based on tandem single side-band modulation

摘要

A novel scheme for optical millimetre-wave (mm-wave) generation based on tandem sub-carrier multiplexing in hybrid communication systems is suggested. The method is analysed mathematically for optimum settings. The tandem single side-band (TSSB) method is tolerant to fibre chromatic dispersion. However, the TSSB technique is prone to critical interference of unwanted harmonics which may result in poor data transmission bit error rate (BER). Based on the proposed mathematical derivation for TSSB modulation, a framework is provided to enhance the mm-wave generation system performance. Up to 2 Gb/s data transmission over multiple 60 GHz sub-bands is considered. The model includes a single-mode fibre with chromatic dispersion factor of 16 ps/(nm km). Two cascaded dual electrode Macha??Zehnder modulators are used to generate TSSB 60 GHz sub-bands. Three oscillators are required to generate two tandem mm-wave signals. A proper selection of these three frequencies is vital to guarantee a successful data transmission. Mathematical analysis is carried out to verify the proposed scheme and a summary of appropriate frequency sets is presented and discussed. The BER curves are obtained. The results verify that the TSSB-based mm-wave generation framework proposed in this study guarantees data transmission with an acceptable BER.