Dual-polarization Dual-parallel Mach-Zehnder Modulator Research Articles

Simultaneous frequency upconversion and phase coding of a radio-frequency signal for photonic radars.

We report a photonic approach to simultaneously realize frequency upconversion and phase coding of a radio-frequency (RF) signal based on polarization manipulation of optical signals. An intermediate frequency (IF) signal is upconverted to the local frequency (LO) band using a dual-polarization dual-parallel Mach-Zehnder modulator, while a high-speed polarization modulator is used to realize high-speed phase coding of the upconverted signal. The key advantage of the proposed method is that no optical or electrical filters are required to remove the residual IF, LO, and undesired downconverted signals, which ensures a broad operation bandwidth, excellent isolation, and wide tunability. The proposed scheme is theoretically analyzed and experimentally verified.

Photonic harmonic up-converter based on a self-oscillating optical frequency comb using a DP-DPMZM

A photonic harmonic up-converter based on a self-oscillating optical frequency comb (OFC) utilizing an integrated dual-polarization dual-parallel Mach–Zehnder Modulator (DP-DPMZM) is proposed and experimentally demonstrated. One DPMZM is used to generate the optoelectronic oscillator (OEO)-based OFC, and the rest one is used to generate the optical-modulated intermediate frequency (IF) signal. Beating these two signals, the up-converted signals at different bands would be obtained. As the OFC is generated based on the OEO loop, phase noise can be very low, ensuring good phase noise properties of the up-converted signals. Moreover, frequency spacing between the combs is dependent on oscillating frequency of the OEO, which can be as large as tens of gigahertz. Thus IF signals with large bandwidth can be up-converted to RF bands without aliasing. Experimentally, the 2.5 GHz IF signal is simultaneously up-converted to 13.3, 24.1, and 34.9 GHz by a self-oscillating 7-line OFC spacing at 10.8 GHz. Owing to good phase noise property of the OEO, the up-converted signals at 13.3 and 24.1 GHz maintain the phase noise of the IF signal from 1 KHz to 100 KHz offset. The results show that the converter is promising for multi-band radar and satellite navigation applications.

Dual-Polarization Dual-Parallel MZM and Optical Phase Shifter Based Microwave Photonic Phase Controller

A new microwave photonic phase controlling structure that can realize a continuously tunable 0 $^{\circ}$ to 360 $^{\circ}$ phase shift using only one DC voltage control is presented. Unlike other phase controlling structures, the radio-frequency (RF) signal phase shift produced by the new phase controller has a predefined linear relationship with the control voltage. This enables users to easily determine the control voltage needed to realize the desired RF signal phase shift. The microwave photonic phase controller is based on an integrated dual-polarization dual-parallel Mach–Zehnder modulator (DPMZM) and a polarization-dependent optical phase shifter. It is suitable for realizing multiple RF signal phase shifts, which are required in beamforming applications. Experimental results are presented which demonstrate the realization of a continuously tunable $-$ 180 $^{\circ}$ to 180 $^{\circ}$ phase shift with little phase and amplitude variations over a wide frequency range, as well as a linear RF signal phase shift to control voltage relationship.