Method of high-precision free-space distance measurement for noncooperative targets.

Aimed at high-precision distance measurement for noncooperative targets in free space, a spatial distance measurement method is proposed. Based on the concept of optical carrier-based microwave interferometry, this method extracts distance information from the radiofrequency domain. The interference model of broadband light beams is established, and the optical interference can be eliminated by using a broadband light source.

Driving system for Mach-Zehnder electro-optic modulators in microwave photonics.

In order to obtain a modulation signal with high bandwidth and highly stable output power without distortion, an electro-optic modulator driving system with quick response to the input signal is designed in this paper. The system mainly includes three parts: power supply module, microwave signal generation module, and automatic gain control (AGC) module. The power supply module provides appropriate voltage and current for other two modules.

Method of high-precision spatial distance measurement based on optical-carried microwave interference.

High-precision spatial ranging plays a significant role in both scientific research and industrial practice. However, it is difficult for existing equipment to achieve high speed, high precision, and long distance simultaneously. Inspired by the concept of optical carrier-based microwave interferometry (OCMI), this paper reports a method of high-precision spatial distance measurement.

Ranging system based on optical carrier-based microwave interferometry.

To compensate for the refractive index errors in optical carrier-based microwave interferometry (OCMI), a ranging system is designed to measure the single-arm optical path of OCMI. A high-speed photodetector and a downconversion method are used to acquire the microwave envelope of the interference signal. A Hilbert transformation is used to realize phase detection.