We analytically study received waveform asymmetries induced by chromatic dispersion (CD) for signed CD monitoring in differential quadrature phase-shift keying (DQPSK) systems and show that the asymmetries are results of differential detection and the ±π/4 phase shifters used in conventional DQPSK receivers. The theoretical insights developed help explain various published results on signed CD ...

In this paper, a precise method for calculating the bit-error rate (BER) of a discrete cosine transform (DCT)-based orthogonal frequency-division multiplexing (OFDM) system on additive white Gaussian noise (AWGN) channels for a Multicarrier-CDMA (MCCDMA) is derived and its BER performance will be compared with the FFT based MC-CDMA. These accurate results are used to examine and compare the BER...

Benefiting from the high spectrum efficiency and power efficiency, 6PolSK-QPSK (6-ary polarization-shift keying quadrature phase-shift keying) is a promising modulation format in coherent optical communication. We proposed a novel structure to generate the 6PolSK-QPSK with two dual-drive MZMs. Simulation results show that the proposed structure can generate 6PolSK-QPSK effectively and the perfo...

In this paper, we propose an optical millimetre wave radio-over-fibre (mm-wave RoF) system that uses a dual drive Mach Zehnder modulator (DD-MZM), which is biased at the maximum transmission biasing point, to generate an optical double sideband-suppressed carrier. The input to the DD-MZM are binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), 8-phase shift keying (8-PSK) and...

in this paper, we propose an optical millimetre wave radio-over-fibre (mm-wave rof) system that uses a dual drive mach zehnder modulator (dd-mzm), which is biased at the maximum transmission biasing point, to generate an optical double sideband-suppressed carrier. the input to the dd-mzm are binary phase shift keying (bpsk), quadrature phase shift keying (qpsk), 8-phase shift keying (8-psk) and...

We demonstrate a flexible-bandwidth network testbed with a real-time, adaptive control plane that adjusts modulation format and spectrum-positioning to maintain quality of service (QoS) and high spectral efficiency. Here, low-speed supervisory channels and field-programmable gate arrays (FPGAs) enabled real-time impairment detection of high-speed flexible bandwidth channels (flexpaths). Using p...