DTFMS Radiating Cable Distance-to-Fault Measure System

Tunnels are critical components of transport infrastructure and highly reliable and available radio coverage in tunnels is essential for tunnel management, mission critical (Tetra / GSM-Rail / signaling / track- to-train radio / PMR / DMR / AM / FM) and commercial (2G, 3G, 4G and future 5G) wireless services in various frequency bands. Especially in train and metro tunnels, leaky cables seem to be the only solution because of the masking effects of the trains.

So, leaky cable, which is the key factor to radio communication system in tunnel, how to monitoring and fast & accurate fault locating are critical issues to tunnel management, telecom operator, system owner or maintenance team, due to the difficulty in making repair works in the tunnel while the train is in operation.

Based upon Software Define Radio (SDR) technique, HELIOS® DTFMS™ Radiating Cable Distance-to-Fault Measure System is a powerful leaky cable performance monitoring platform, it is designed to be easily integrated into existing or new radiating cable system in tunnel by compact size and low power consumption, and enable keeping precisely measures parameters of the leaky feeder such as VSWR, Return-Loss etc., and conduct real-time verification, monitoring and fault locating for the radiating cable system

HELIOS® DTFMS™ Radiating Cable Distance-to-Fault Measure System mainly consists of four parts as below:

  • DTFMS™ Fiber Converter Rack-mount Chassis (FCRMC): The DTFMS™ Fiber Converter Rack-mount Chassis is specially designed to accommodate optical converter for central power supply, saving space and power cables. Up to 16 slots Fiber Converter support
  • DTFMS™ Rack-mount Switch: The DTFMS™ Rack-mount switch provide an easy way to collect all the Measure Node data by Console Unit
  • DTFMS™ Console Unit (CU): Generally will be deployed on radio BTS room and be in charge to centrally monitor and manage all DTFMS™ Measure Node (MN) in network through fiber link, it will receive data (such as operation status of device, alarm message, operation performance of leaky cable, distance to fault, timestamp etc.) from MNs
  • DTFMS™ Measure Node (MN): it will be connected to the leaky cable via a customized Combiner and it will keep monitoring and measuring the performance of leaky cable and regularly send measurement result and alarm message to CU via fiber link

The DTFMS utilizes an embedded WEB management system for system configuration and network monitoring. The embedded WEB management system collects key performance and alarm information from leaky cable and send back alarm information to Helios® Network Monitoring System through fiber link (Cat 5e Cable) or directly integrated into customer’s existing NMS through SNMP V2&V3 trap with a MIB file

Typical mounting options for the DTFMS include pole-mount and wall-mount. And the enclosure of the DTFMS is fully sealed IP-67 rated with compact design, which minimizes maintenance and is ideal for harsh environments

  • Real-time monitoring operation performance of leaky cable system in tunnels and accurate fault locating function
  • Low power consumption and compact design
  • Easily integrated into existing radiating cable system
  • More 2KM maximum measurement distance
  • Accurate fault locating performance as +/-1 meter error range
  • Tiny low Tx power with customized frequency covering from 200-2500MHz without interfere with current radio communication systems
  • Supports 2 RF ports for Radiating cable measurement
  • RJ-45 port in MN for Local Control
  • Embedded optical port in MN for data backhaul
  • SNMP V2 & V3 support with a MIB File
  • IP-67 rated aluminum enclosure for harsh environments and both support pole and wall mounted
  • Efficiently minimize total cost of leaky cable maintenance for tunnel management, telecom operator, system owner and maintenance team

Rack-mount Switch

Number of Ethernet Port: 24

Data Transfer Rate: 100 Mb per second

LED: LED indicator each port for Link/Ack

Power Supply: 100~240V AC

Dimension: 19” 1U

Weight: Max.3kg

Fiber Converter Rack-mount Chassis

Capacity: Up to 16 slots (Fiber converter)

LED: LED indicator each port for Link/Ack

Power Supply: 100~240V AC

Dimension: 19” 2U

Weight: Max.6.5kg

Console Unit

Connector: 2 * RJ-45 ports

Temperature Range: -25 ℃ to +55 ℃

Relative Humidity: Max 85%

MTBF: Min. 50,000 Hours

Power Supply (External): 100~240V AC

Local Control: RJ-45 Port for Local Control or connect to Switch

Remote Control: Additional RJ-45 Port for Remote Control

Dimension: 19” 1U

Weight: Max.3kg

Measure Node

Main Communication System Frequency Range: Public Safety and Cellular Band

Measurement Frequency: Customized bandwidth in the range 200-2500MHz; Typical 520-560MHz

Max Input Power without Damage: 10dBm

Max Output Power: 5dBm

Number of Measurement Points: 1024

Return Loss Measurement Range: 0 to 100dB

Frequency Accuracy: 0.05ppm

Return Loss Measurement Accuracy: 0.01dB

Max Fault Detection Location Distance: 2000M

Distance Accuracy: Max ±1M

No. RF Port: Up to 2 RF Ports

Connector: RF: (7/16 DIN or N-type Female) * 2; Monitor: RJ-45 * 1 (Local); SC/APC * 1 (Remote)

I/O Impedance: 50 Ohm

Temperature Range: -25 ℃ to +55 ℃

Relative Humidity: Max 85%

MTBF: Min. 50,000 Hours

Power Supply (External): 100~240V AC

Power Consumption: Max 8W

Local Control: RJ-45 Port for Local Control

Remote Control: Optical Port for data backhaul

IP Rating: IP 67

Dimensions: 316*225*132mm

Weight: Max. 8kg