In this paper, we propose and numerically simulate a microwave photonic phase-tunable frequency converter (MPPTFC) without optically filtering to realize both frequency up- and down-conversion and a full 360° phase-shift for the microwave signal based on an integrated dual-polarization dual-parallel Mach–Zehnder modulator (DP-DPMZM). In the proposed scheme, both microwave RF signal and frequency-tunable local oscillator (LO) are modulated on the lightwave by single-sideband carrier suppression (SSB-CS) modulation to generate optical orthogonally polarized optical tones carrying RF signal with up- or down-converted frequency. A PolM that can support lightwave modulation with opposite modulation indices in transverse electric (TE) and transverse magnetic (TM) modes is used to introduce a phase difference between the two modes. Then the orthogonally polarized optical tones are aligned into a single polarized state by a polarizer (Pol) and detected by a photodiode (PD), a frequency-converted and phase-shifted microwave signal can be obtained. Simulation results demonstrate that the proposed MPPTFC can up-/down-convert the microwave signal with a tunable frequency shift of LO frequency and realize a 360° continuously tunable phase shift via the DC bias voltage of the PolM simultaneously.

在本文中，我们提出并进行了数值模拟的微波光子相位可调变频器（MPPTFC），无需进行光学滤波，即可基于集成的双频技术实现微波信号的上，下变频和完整的360°相移极化双并联马赫曾德尔调制器（DP-DPMZM）。在提出的方案中，微波RF信号和频率可调本地振荡器（LO）在光波上通过单边带载波抑制（SSB-CS）调制进行调制，以产生正交的偏振光音调，其携带带有向上或向下的RF信号转换频率。在横向电（TE）和横向磁（TM）模式下可以支持具有相反调制指数的光波调制的PolM用于在两种模式之间引入相位差。然后，通过偏振器（Pol）将正交偏振的光调对准单偏振态，并通过光电二极管（PD）进行检测，可以获得经过频率转换和相移的微波信号。仿真结果表明，所提出的MPPTFC可以通过LO频率的可调频移对微波信号进行上/下转换，并同时通过PolM的DC偏置电压实现360°连续可调的相移。