In the construction of a 2.2 km highway tunnel in Shenzhen, persistent communication blackspots threatened to stall progress. Although excavation had reached 1,500 meters, the mobile signal vanished as early as 400 meters in, making coordination between crews nearly impossible. Without stable connectivity, daily reporting, safety checks, and logistical updates ground to a halt. At this critical juncture, the project owner turned to Lintrate to deliver a turnkey solution that would guarantee uninterrupted mobile signal throughout the working area.
Tunnel
Drawing on its extensive experience in telecom infrastructure, Lintrate rapidly assembled a dedicated design-and-deployment team. After in-depth consultations with the client and a thorough survey of the site’s geotechnical and RF conditions, the team selected a high‑power fiber optic repeater system as the project’s backbone.
Schematic Diagram
Initial tests at the portal revealed that the source signal’s SREP value was below –100 dBm (where –90 dBm or higher denotes acceptable quality). To overcome this, Lintrate engineers switched to a panel‑style antenna to boost reception gain, ensuring a robust input for the repeater network.
The core setup employed a dual‑band, 20 W fiber optic repeater. The Base Unit was stationed at the tunnel entrance, while the Remote Unit resided 1,500 meters inside. A 5 dB, 2-way splitter routed the amplified signal along cross‑passages, with large panel antennas back‑to‑back to blanket both sides of the tunnel bore with coverage.
Base Unit of Fiber Optic Repeater
Remarkably, Lintrate’s crew completed installation in just one day, and by the following morning, testing confirmed full compliance with the client’s performance requirements. This swift turnaround not only resolved the mobile signal blackout but also minimized disruption to the tunnel schedule, earning high praise from the project owner.
Remote Unit of Fiber Optic Repeater
To future‑proof the network, Lintrate implemented a flexible, redundant design that allows the Remote Unit and in‑tunnel antennas to be repositioned as excavation advances. As the tunnel extends, on‑the‑fly adjustments maintain seamless coverage, ensuring crews always have access to reliable communications.
With 13 years of expertise and exports to over 155 countries, Lintrate is a leading manufacturer of commercial mobile signal boosters, fiber optic repeaters, and antenna systems. Our proven track record across diverse project scenarios makes us the trusted partner for any tunnel or infrastructure mobile signal challenge.
Post time: Apr-22-2025