A Novel Approach to Realizing SSB Modulation With Optimum Optical Carrier to Sideband Ratio

Novel Vestigial Sideband Modulation Scheme to Enhance the SNR in Radio Over Fiber Systems

“…Some slightly complex methods have been reported for achieving the SNR optimization goal [6], [7], [11]. These methods include DMZM with tunable optical filter, using polarization modulators, optical injection locked laser based technique, etc.…”

“…Thus, optical amplifier is also required to enhance the optical power. Another approach of operating at OCSR = 0 dB has been demonstrated in [11] using a strong optical injection locked laser. This method requires two lasers and precise measurements.…”

“…1.1 we will show the generation method of the OVSB and OSSB scheme using the series MZM and PM configuration. Also, we describe how OVSB method is advantageous to optimize the SNR of the link in comparison to the OCSR = 0 dB method of [6], [11]. Section 2 gives the clear analytical description on the OSSB and OVSB generation method using the series MZM and PM configuration.…”

Phase-coherent orthogonally polarized optical single sideband modulation with arbitrarily tunable optical carrier-to-sideband ratio

“…The receiver sensitivity could be enhanced by simply optimizing the OCSR to improve the performance of the entire system [23][24][25]. Up to now, several approaches have been verified to achieve the OSSB modulation with tunable OCSR based on an OSSB generator incorporating with a narrow band notch FBG or a polarization maintaining fiber Bragg grating (PM-FBG) [23] or a DPMZM combining with a 90-degree phase shifter [26] or optical injection-locked laser [27] or multimode interference coupler and three optical phase-modulator waveguides [28]. However, the working bandwidth for the PM-FBG-based method is limited and the system has a poor long-term stability and is wavelength dependent.…”

“…Therefore, the OCSR is continuously tunable by simply adjusting the bias voltages of the lower arm modulator. Compared with the [19,23,27,28], the OCSR of the proposed method has a wider range, a better stability, and a smaller footprint. The frequency shifting optical signal from the upper modulator and the optical carrier from the lower modulator are combined together at the output of the DP-QPSK modulator with orthogonal SOP.…”