电子学报 ›› 2022, Vol. 50 ›› Issue (4): 782-788.DOI: 10.12263/DZXB.20210746

所属专题: 微波光子与相关元件技术 微波光子技术 长摘要论文

• 微波光子技术 • 上一篇    下一篇

基于PDM-DPMZM的大动态范围微波光子I/Q下变频系统

史芳静, 樊养余, 王鑫圆, 康博超, 陈博, 高永胜   

  1. 西北工业大学电子信息学院,陕西 西安 710072
  • 收稿日期:2021-06-14 修回日期:2021-12-27 出版日期:2022-04-25
    • 通讯作者:
    • 高永胜
    • 作者简介:
    • 史芳静 女,1995年3月出生,陕西咸阳人.2017年毕业于南京理工大学探测制导与控制技术专业,现为西北工业大学电子信息学院硕博连读生.主要从事微波光子信号处理、光载射频通信等方面的研究工作. E-mail: fangjing_shi@mail.nwpu.edu.cn
      樊养余 男,1962年4月出生,陕西蓝田人.分别于1982年、1992年在陕西科技大学获得学士、硕士学位,1999年在西北工业大学获得博士学位.现为西北工业大学电子信息学院教授,博士生导师.主要从事虚拟现实技术、数字信号处理理论与应用等方面的研究工作. E-mail: fan_yangyu@nwpu.edu.cn
      高永胜(通讯作者) 男,1989年9月出生,河南漯河人.分别于2011年、2014年和2016年在西安电子科技大学获得学士、硕士和博士学位.现为西北工业大学副教授,硕士生导师.主要从事微波光子信号处理、光载射频通信、微波光子卫星通信、微波光子雷达等方面的研究工作. E-mail: ysgao@nwpu.edu.cn
    • 基金资助:
    • 国家自然科学基金 (62171374); 博士后创新人才支持计划 (BX201700197); 中国博士后科学基金 (2017M623238); 陕西省重点研发计划 (2021GY-096)

Large Dynamic Range Microwave Photonic I/Q Down-Conversion System Based on PDM-DPMZM

SHI Fang-jing, FAN Yang-yu, WANG Xin-yuan, KANG Bo-chao, CHEN Bo, GAO Yong-sheng   

  1. School of Electronics and Information, Northwestern Polytechnical University, Xi’an, Shaanxi 710072, China
  • Received:2021-06-14 Revised:2021-12-27 Online:2022-04-25 Published:2022-04-25
    • Corresponding author:
    • GAO Yong-sheng
    • Supported by:
    • National Natural Science Foundation of China (62171374); Post doctoral Innovative Talents Support Program (BX201700197); China Postdoctoral Science Foundation (2017M623238); Key R&D Pan of Shaanxi Province (2021GY-096)

摘要:

针对被目前大多微波光子I/Q下变频系统忽视的非线性失真问题,提出了一种基于偏振复用双平行马赫增德尔调制器(Polarization Division Multiplexing Dual-Parallel Mach-Zehnder Modulator,PDM-DPMZM)的大动态范围微波光子I/Q下变频系统.利用PDM-DPMZM并行地调制射频、本振和镜像信号,调节调制器的直流偏置并进行驱动信号功率控制,能够实现I/Q下变频及镜像干扰抑制,同时抑制三阶交调失真.实验结果表明,所提方案最终可以实现超过44 dB的镜像抑制,系统的无杂散动态范围达到110.5 (dB·Hz4/5).在5~20 GHz工作频率范围内,相位失衡和幅度失衡分别低于0.8°和0.6 dB.

长摘要
受限于电子瓶颈,传统微波I/Q混频器存在频率依赖、宽带I/Q幅相失衡和电磁干扰等问题,微波光子变频技术是一种能够解决以上问题的替代方案。针对被目前大多微波光子I/Q下变频系统忽视的非线性失真问题,提出了一种基于偏振复用双平行马赫增德尔调制器(Polarization division multiplexing dual-parallel Mach-Zehnder modulator,PDM-DPMZM)的大动态范围微波光子I/Q下变频系统。利用集成的PDM-DPMZM并行地调制射频(Radio frequency,RF)、本振(Local oscillator,LO)和镜像信号。通过控制调制器的直流偏置,在RF和LO信号之间引入90°相位差,构造了I/Q下变频通道,并基于Hartley结构,实现了镜像抑制。同时,进行RF驱动信号功率调控,还能够抑制下变频过程中的三阶交调失真,进而改善系统的动态范围。实验结果表明,所提方案能够将10.5GHz的RF信号下变频到0.5GHz,并构建I/Q下变频通道。在5-20GHz工作频率范围内,I/Q相位失衡和幅度失衡分别低于0.8°和0.6dB。配合90°电耦合器使用,单音输入下可以实现超过44dB的镜像抑制,系统的无杂散动态范围达到110.5dB·Hz4/5。在16QAM调制格式、30MHz带宽的矢量信号测试下,系统解调误差向量幅度(Error Vector Magnitude,EVM)约为6.2%。所提微波光子I/Q下变频系统具有工作带宽大、镜像抑制好、动态范围高等优点,因此在超外差接收、零中频接收、矢量信号分析和其他微波测量等系统中极具应用潜力。

关键词: 微波光子, 镜像抑制, I/Q下变频, 动态范围, 偏振复用双平行马赫增德尔调制器

Abstract:

Aiming at the nonlinear distortion problem ignored by most microwave photonic I/Q down-conversion systems, a large dynamic range microwave photonic I/Q down-conversion system based on the polarization division multiplexing dual-parallel Mach-Zehnder modulator (PDM-DPMZM) is proposed. The PDM-DPMZM is used to modulate the radio frequency signal, local oscillator signal, and image signal in parallel. By adjusting the DC bias of the modulator and the powers of the drive signals, the I/Q down-conversion and image interference suppression can be realized. The third-order intermodulation distortion can be suppressed at the same time. Experimental results show that the proposed scheme can achieve an image rejection ratio of more than 44 dB. The spur-free dynamic range can reach 110.5 dB·Hz4/5. In the 5-20 GHz operating frequency range, the phase imbalance and amplitude imbalance are lower than 0.8° and 0.6 dB, respectively.

Extended Abstract
Due to the electronic bottleneck, traditional microwave I/Q mixer suffers the problems of frequency dependence, broadband I/Q amplitude and phase imbalance and electromagnetic interference. Microwave photonic frequency conversion technology is a potential alternative to solve the above problems. Aiming at the nonlinear distortion problem ignored by most microwave photonic I/Q down-conversion systems, a large dynamic range microwave photonic I/Q down-conversion system based on the polarization division multiplexing dual-parallel Mach-Zehnder modulator (PDM-DPMZM) is proposed. The radio frequency (RF), local oscillator (LO), and image signals are modulated in parallel with the integrated PDM-DPMZM. By controlling the DC bias of the modulator and introducing a 90° phase difference between the RF and LO signals, an I/Q down-conversion channel is constructed. Based on the Hartley structure, the image rejection is achieved. At the same time, when the power of the RF driving signal is controlled, the third-order intermodulation distortion in the down-conversion process can also be suppressed, thereby improving the dynamic range of the system. The experimental results show that the proposed scheme can down-convert the 10.5 GHz RF signal to 0.5 GHz, and construct I and Q down-conversion channels. In the operating frequency range of 5-20 GHz, the I/Q phase imbalance and amplitude imbalance are lower than 0.8° and 0.6 dB, respectively. When used with a 90° electric coupler, the system can achieve image rejection of more than 44 dB under the single-tone test, and the spurious-free dynamic range is up to 110.5 dB·Hz4/5. Under the vector signal test with 16QAM modulation format and 30 MHz bandwidth, the system demodulation error vector magnitude (EVM) is about 6.2%. The proposed microwave photonic I/Q down-conversion system has the advantages of large operating bandwidth, good image rejection, and high dynamic range, so it has great application potential in superheterodyne reception, zero intermediate frequency reception, vector signal analysis, and other microwave measurement systems.

Key words: microwave photonics, image rejection, I/Q down-conversion, dynamic range, polarization division multiplexing dual-parallel Mach-Zehnder modulator

中图分类号: