Research on Integrated Technology for Simultaneous Detection, Ranging, and Data Transmission Using an Optical DSSS Transceiver

With the development of space laser networks, miniaturization and lightweight design have become inevitable trends in laser terminal development. In laser links, functions such as spot position measurement, ranging, and data transmission are usually performed by multiple independent units. Integrating these three functions can effectively reduce the size of the opto-mechanical structure and save space within the optical transceiver, thereby supporting the lightweight and compact growth of laser terminals. This paper presents an integrated scheme based on an optical direct-sequence spread-spectrum (DSSS) quadrant detector (QD) and regenerative codes, which enables spot position measurement, ranging, and data transmission through an optical transceiver. The core of this approach involves using a code tracking loop to perform correlation gain calculation, phase comparison, and demodulation of the pseudo-noise code-modulated laser signal, thereby achieving all three functions simultaneously. A desktop experimental system was built to test and verify the scheme’s accuracy and precision. The system achieved a ranging accuracy of 14 mm (1σ), a spot position measurement accuracy of 0.83 μm (1σ) at the target center, and a communication sensitivity of −31 dBm at a 10−4 bit error rate (BER) with a data rate of 1 Kbps. This study provides a reference for future lightweight optical terminals.