Next Article in Journal
Highly Accurate and Fully Automatic 3D Head Pose Estimation and Eye Gaze Estimation Using RGB-3D Sensors and 3D Morphable Models
Previous Article in Journal
A Novel Connectivity-Based LEACH-MEEC Routing Protocol for Mobile Wireless Sensor Network
Previous Article in Special Issue
RECRP: An Underwater Reliable Energy-Efficient Cross-Layer Routing Protocol
Article Menu

Export Article

Open AccessArticle
Sensors 2018, 18(12), 4279;

Reference Phase Stabilizer for Distributed Underwater Sonar Systems

The Institute of Marine Electronic and Intelligent System, Ocean College, Zhejiang University, Zhoushan 316021, China
Authors to whom correspondence should be addressed.
Received: 30 September 2018 / Revised: 12 November 2018 / Accepted: 30 November 2018 / Published: 5 December 2018
(This article belongs to the Special Issue Underwater Sensing, Communication, Networking and Systems)
Full-Text   |   PDF [7204 KB, uploaded 5 December 2018]   |  


An optical fiber is a promising approach for data and clock transmission in distributed underwater sonar systems. However, synchronization is a critical challenge in distributed sonar systems, which mandates accurate clock synchronization down to a sub degree. Potential phase misalignment is caused by fiber length variations. In this paper, we propose a fiber-based phase stabilizer method to achieve accurate clock synchronization among sensor nodes. We use fiber-based feedback loop between sensor nodes and central station unit to monitor phase variations. Subsequently, we leverage phase shifters symmetrically arranged on the forward lane and feedback lane to compensate real-time phase variation and maintain high-precision synchronization. Besides, an ambiguity eliminator circuit is designed to remove the clock’s cyclic ambiguity. Both analysis and experimental results suggest that the proposed phase stabilizer can achieve 10 MHz reference clock synchronization within 0.4 degree. We also analyze the impact of the reference clock’s phase error on the system range detection accuracy, which indicates that the proposed phase stabilizer can greatly improve detection accuracy of sonar systems. View Full-Text
Keywords: distributed sonar systems; reference dissemination; phase synchronization distributed sonar systems; reference dissemination; phase synchronization

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Yang, L.; Dang, R.; Song, C.; Xu, Z. Reference Phase Stabilizer for Distributed Underwater Sonar Systems. Sensors 2018, 18, 4279.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top