Interoperation Scheme for Dedicated Wireless Trunking Systems in Urban Rail Transit

• Published in: Chengshi guidao jiaotong yanjiu
• Main Authors: XU Lijin, GONG Jiansheng
• Format: Article
• Language: Chinese
• Published: Urban Mass Transit Magazine Press 2025-06-01
• Subjects: urban rail transit; dedicated wireless trunking system; interoperation scheme
• Online Access: https://umt1998.tongji.edu.cn/journal/paper/doi/10.16037/j.1007-869x.20230499.html

[Objective] In order to meet the requirements for urban rail transit continuous development and metro operation service quality improvement, dedicated wireless trunking systems must achieve interoperation across lines to realize unified network-side dispatching and operational management. [Method] The principle of the TETRA (terrestrial trunked radio) digital trunking system is briefly described, along with the interoperation business requirements of the dedicated wireless trunking system. The interoperation schemes for homogeneous and heterogeneous devices in Wuhan Rail Transit dedicated wireless trunking system are introduced. Various schemes are compared and analyzed in depth in terms of additional equipment requirements, interface types, interoperation levels, roaming talk group capacity, compatibility with broadband systems, and construction costs. Based on the development and application of SIP (session initiation protocol) in dispatching systems, an interoperation scheme for a network-wide unified wireless dispatching system based on SIP protocol is proposed. [Result & Conclusion] The above-mentioned interoperation scheme based on SIP involves the SIP-based protocol conversion for each TETRA digital trunking system or the broadband system original proprietary protocol. The voice control signaling of each TETRA digital trunking system or broadband system is converted into SIP voice call signaling according to RFC3261, and the short data control signaling is converted into SIP short data signaling according to RFC3428, thereby enabling full-featured interoperation of heterogeneous TETRA digital trunking systems or broadband systems. This scheme breaks the technical barriers imposed by foreign manufacturers such as AIRBUS and Motorola who do not open interfaces and effectively resolves the issue of cross-line operation across multi-brand TETRA digital trunking system in Wuhan Rail Transit.