For the first time, a trial of TETRA technology has been carried out with a radio user in the United States, to demonstrate the multiple features and functionality of the TETRA system and the strength of TETRA-enabled applications.

Participating in the trial was NJ Transit, the US’s largest state-wide transport operator. NJ Transit provides bus, rail and light rail services linking major points in New Jersey, New York and Philadelphia.

The pilot system, a two-site network, was based on TETRA equipment provided by PowerTrunk (the name used in North America by the Spanish manufacturer Teltronic), with Alcatel-Lucent acting as primary system integrator. It included PowerTrunk-T base stations, mobiles, hand portables, a line dispatcher and a switch to integrate NJ Transit’s ‘legacy’ VHF system. Testing by PowerTrunk began in November.

In addition, the network was integrated with an existing computer-aided dispatch system and a PowerTrunk PABX/PSTN gateway to allow cellular-like full duplex communications between cell or public switched phones and PowerTrunk radios.

FCC-certified

“This is the first TETRA trial in the United States and the only one that entirely utilizes equipment certified by the FCC”, commented  José Martín, chief operating officer of PowerTrunk. “We are delighted to team with Alcatel-Lucent for this project and I hope that we will co-operate in many others in the future.”

Using the trial network, NJ Transit bus crews could communicate, using voice and data, with operations personnel. Their existing network has a limited data bandwidth and is not spectrally efficient, but the TETRA system provided improved data bandwidth plus 6·25 kHz voice equivalence, to meet regulatory requirements for narrow-band systems in the US. NJ Transit has also piloted other digital land mobile radio (LMR) technologies.

“It is important that NJ Transit conduct technical due diligence on available digital LMR (D-LMR) systems as we move closer to finalizing functional specifications to replace our ageing analogue LMR system”, commented Andrew Schwartz, director of radio communications for NJ Transit. “We must ensure the technology we ultimately acquire through a competitive process is scalable, maintainable, and supports a rich set of features to address current and future Intelligent Transportation System (ITS) applications, including robust data capabilities.

“We chose to pilot PowerTrunk’s TETRA LMR because of their leadership in bringing TETRA to the US, their success in winning FCC type-acceptance for their equipment under Part 90, and their track record of successful transit LMR deployments. To date, results have been positive. We have used the PowerTrunk-T system alongside our legacy LMR system without any interference issues.”

The pilot employed a combination of a leased T1 line and a private optical fibre backbone with routers configured for the ethernet Layer 2 Tunnelling Protocol (L2TP) required by the PowerTrunk-T equipment.

“The existing NJ Transit communications backbone enabled us to efficiently and smoothly reconfigure the network to support TETRA”, said Nicola Guidara, director of transportation market segment for Alcatel-Lucent’s Americas Region. “Thanks to our close collaboration with PowerTrunk, together we were able to provide NJ Transit with an advanced TETRA network.”