New Jersey Transit Corp. TETRA TRS

[Thunderbolt]

NJ Transit has filed an application that maybe the first of more to come, to construct a TETRA digital trunking system. The contractor selected to build this new TRS is Motorola. The first site will be located in Atlantic City. More information is available on the FCC Web site:

Application

Supporting Letter

73's

Ron

[chiefjohnson]

Can anyone fill me in on what a TETRA trunked system is and what benefit over regular trunking it will have and what is wrong with the current 800 system they have? Thkx

[elias1988]

TETRA - The RadioReference Wiki

[RadioDitch]

Whats the benefit? Honestly? There really isn't one. It's just another digital protocol, this one based on European standards. Basically they drank the Kool-Aid. They system will replace the current Motorola Type IIi system altogether. This means the migration of all light rail, bus, and administrative operations. There is also the potential of complete migration of NJTPD onto the system and off VHF.

[chiefjohnson]

I know there are some major issues with the NJ Transit system currently. Mostly I think they have under repaired the system puposely to replace it. The only one that's going to make any advantage on this deal is Motorola. With all the sub contracted companies doing Transit bus work (Lakeland/DeCamp/Trans-Bridge/Carefree) in addition to the hundreds of NJ Transit buses, trains and light rail I can't imagine what the cost is to buy new mobile equipment

[gotdigital]

Originally Posted by RadioDitch

Whats the benefit? Honestly? There really isn't one. It's just another digital protocol, this one based on European standards. Basically they drank the Kool-Aid. They system will replace the current Motorola Type IIi system altogether. This means the migration of all light rail, bus, and administrative operations. There is also the potential of complete migration of NJTPD onto the system and off VHF.

Better they drank this cool-aid than the overpriced P25 cool-aid.

[RadioDitch]

Originally Posted by gotdigital

Better they drank this cool-aid than the overpriced P25 cool-aid.

I disagree. I think P25 would have been a more sensible move. Overpriced or not, at least it would have been a common standard, rather than what is basically a foreign standard. It would have made interop simpler also on the law enforcement end. And let's be honest. This is New Jersey Transit. Any excuse they can find to spent some big bucks, they'll take. And as chiefjohnson noted, regardless of the protocol, they're going to be hundreds of thousands of dollars in equipment to buy just for the subcontract carriers. NJT is responsible for providing them the communications equipment.

[gotdigital]

Originally Posted by RadioDitch

I disagree. I think P25 would have been a more sensible move. Overpriced or not, at least it would have been a common standard, rather than what is basically a foreign standard. It would have made interop simpler also on the law enforcement end. And let's be honest. This is New Jersey Transit. Any excuse they can find to spent some big bucks, they'll take. And as chiefjohnson noted, regardless of the protocol, they're going to be hundreds of thousands of dollars in equipment to buy just for the subcontract carriers. NJT is responsible for providing them the communications equipment.

In my opinion; TETRA is the most common digital radio platform in the World. So, while it's "foreign " here, P25 is foreign in most of the World. I also have yet to see the day that law enforcment needing interoperability with a transit service.

[robertpearsall]

As a ex Firefighter & EMS I can name more then a 100 resons why they need interoperability between transit and Public Saftey the # 1 reason is the world we live in and the likely hood of attacks on to rail systems I am not saying every bus and train but yes there needs to be interoperability.

[mlmummert]

Originally Posted by gotdigital

In my opinion; TETRA is the most common digital radio platform in the World. So, while it's "foreign " here, P25 is foreign in most of the World. I also have yet to see the day that law enforcment needing interoperability with a transit service.

NJT has their own police department.


Sent from my iPad using Tapatalk

[Chauffeur6]

Originally Posted by gotdigital

In my opinion; TETRA is the most common digital radio platform in the World. So, while it's "foreign " here, P25 is foreign in most of the World.

That's all fine and well, except we live in North America, where P25 is the accepted and de facto standard for public safety digital. What the rest of the world does is, frankly, irrelevant when it comes to public safety radios. I have yet to see the day that we need public safety radio interoperability with Europe or Asia.

Originally Posted by gotdigital

I also have yet to see the day that law enforcment needing interoperability with a transit service.

You appear to be unfamiliar with New Jersey Transit, based on that statement. They are not just some little "bus company", they are one of the largest public transportation systems in the entire US. As mlmummert stated, they have their own police department which has statewide jurisdiction, and they frequently interact with the New Jersey State Police, the MTA PD, the Port Authority PD, and local law enforcement. So yes, interoperability is an issue here. This ain't just Ralph Kramden talking to the local dispatcher we're talking about here.

[Raccon]

Originally Posted by chiefjohnson

Can anyone fill me in on what a TETRA trunked system is and what benefit over regular trunking it will have and what is wrong with the current 800 system they have? Thkx

Terrestrial Trunked Radio - Wikipedia, the free encyclopedia

[Raccon]

Originally Posted by RadioDitch

Whats the benefit? Honestly? There really isn't one.

TETRA is a truly open standard with proven and certifiable interoperability while still offering a lot more functions than just the basics, in fact TETRA encourages competition between vendors, which results in radios that are much cheaper than those for P25. Honestly.

Originally Posted by RadioDitch

I disagree. I think P25 would have been a more sensible move. Overpriced or not, at least it would have been a common standard, rather than what is basically a foreign standard. It would have made interop simpler also on the law enforcement end.

Which common standard would that be? - P25 isn't equal P25 - analog or digital, conventional vs trunked, encrypted or not, FDMA/TDMA etc.
Sounds all great on paper but reality has shown that true interoperability isn't actually that easy to achieve. Not to mention all those proprietary features added by many P25 vendors on top of that common standard.

Ironically there is only one vendor that claims to offer a true non-proprietary / 100% standards-compliant P25 system, so I would take any claims of 'provides interoperability due to a common standard' with a grain of salt.

Originally Posted by robertpearsall

As a ex Firefighter & EMS I can name more then a 100 resons why they need interoperability between transit and Public Saftey the # 1 reason is the world we live in and the likely hood of attacks on to rail systems I am not saying every bus and train but yes there needs to be interoperability.

Interoperability can come in many different flavors; as indicated above P25 is not known to be the best example but you can inter-connect TETRA with virtually any other system to achieve (at minimum) inter-system voice communication, which is usually the most critical in a multi-agency disaster.

This might also be of interest in case you haven't seen it yet (NJT mentioned from page 30 onwards): http://tetraforum.pl/doc/TETRA-Congr...er-Clemons.pdf

[lep]

Originally Posted by Raccon

Terrestrial Trunked Radio - Wikipedia, the free encyclopedia

The wiki is not really complete. Yes, the "TE" does stand for terestrial but that was not where the name came from. The "TE" meant 'trans european' when the standard was developed. Yes TETRA is an ETSI standard that was submitted to the ITU-R for International Standards approval just like APCO submited Project 25 for approval as an International Standard. The P-25 standard is not "owned" by Motorola, many different 'flavors' of P-25 are on the market from different makers. Same as TETRA, different radio makers can bring to the market their own implementation of the Standard.

But the marketing folks figured, wow, Trans European doesn't sound very good to sell outside Europe, let's keep the name and modifiy what the initials mean, hence. TETRA magially became Terestrial etc. Neat?

As far as I know, a scanner maker could purchase a license to market a TETRA scanner if the demand was there and it seemed profitable. (same as the could for D-STAR but they don't think it makes financial sense).

European security services tend to use TETRAPOL which is a different animal and I don't believe they would sell a license for that flavor.

[tvboy08721]

I have been researching information about their new radio system for the last couple of days and I found a comment letter that was filed to the FCC last year, right after NJ Transit awarded the contract to build out the the new TETRA system. What I read here, might answer some questions about the interoperability issue and also explain the intentions of the users of the new system.

ECFS Filing: New Jersey Transit Corporation (11-69) - 04/06/2012

[Raccon]

Originally Posted by lep

The wiki is not really complete. Yes, the "TE" does stand for terestrial but that was not where the name came from. The "TE" meant 'trans european' when the standard was developed.

I does say so in the first sentence.

Yes TETRA is an ETSI standard that was submitted to the ITU-R for International Standards approval just like APCO submited Project 25 for approval as an International Standard. The P-25 standard is not "owned" by Motorola, many different 'flavors' of P-25 are on the market from different makers. Same as TETRA, different radio makers can bring to the market their own implementation of the Standard.

The TETRA standard is pretty clear and includes a comprehensive feature set, something that P25 lacks, and IOP testing ensures compliance with that standard so that a radio from vendor A works in the network from vendor B without too much if any flavoring while that so-called common standard for P25 (more correctly a suit of standards) has a lot of interoperability issues due to the many different architectures allowed.

But the marketing folks figured, wow, Trans European doesn't sound very good to sell outside Europe, let's keep the name and modifiy what the initials mean, hence. TETRA magially became Terestrial etc. Neat?

Sure, the name was changed but it happened a long time ago and considering that TETRA is not just limited to Europe it seems the marketing folks made the right call. Of course it is arguable if the initial name would have stopped TETRA from being successful outside of Europe but who cares now what the name used to be? No one really.

As far as I know, a scanner maker could purchase a license to market a TETRA scanner if the demand was there and it seemed profitable. (same as the could for D-STAR but they don't think it makes financial sense).

That's possible.

European security services tend to use TETRAPOL which is a different animal and I don't believe they would sell a license for that flavor.

1. By now TETRA has caught up if not overtaken TETRAPOL, several European countries operate nation-wide shared TETRA networks for their public safety organizations.
2. They do "sell" it: Tetrapol Publicly Available Specifications

[lep]

Originally Posted by Raccon

I does say so in the first sentence.





1. By now TETRA has caught up if not overtaken TETRAPOL, several European countries operate nation-wide shared TETRA networks for their public safety organizations.
2. They do "sell" it: Tetrapol Publicly Available Specifications

Thanks for the update. I admit I retired in 2009 and have not been to an ITU-R technical meeting since then.
Selling printed copies of the standard and selling a license to a scanner maker to manufacture an implementation are different. It is my understanding from the Forum that all TETRAPOL is natively encrypted.

But that is all just of academic interest, I doubt any scanner makers are toiling away with TETRA plans for the immediate future.

[PM08203]

?why would NJT not contract space on either the existing NJS system or the new passport system?

[kd2pm]

Originally Posted by Thunderbolt

NJ Transit has filed an application that maybe the first of more to come, to construct a TETRA digital trunking system. The contractor selected to build this new TRS is Motorola. The first site will be located in Atlantic City. More information is available on the FCC Web site:

Application

Supporting Letter

73's

Ron

You might want to replace the vendor. Its not Motorola but Power Trunk. Although Motorola makes TETRA equipment for everyone other than the US (They prefer to sell P-25 here), they have not yet made the move to sell their TETRA here in the US.

[902]

I've been casually following the thread and I suppose it's time to jump into the fray. The unstated reason for why TETRA is more beneficial than other technologies is talkpath gain. For one 22 kHz wide channel (a 20 kHz channel for PowerTrunk's "reduced power" TETRA), you get 4 talkpaths. For one repeater station, you have 4 timeslots that can be each used for a separate conversation or data transaction. In DMR ("Mototrbo" and others), for 1 repeater station, you have 2 timeslots. In P25 Phase II, you also have 2 timeslots. So, for deploying a 4 talkpath system, a DMR or P25 Phase II system will be twice as expensive because you need an extra repeater, not to mention those use 12.5 kHz wide channels and half of a channel might be orphaned. This becomes critical on 700 MHz narrowband channels, because they can't effectively be reused in proximity to the other half of the channel.

There is a caveat - P25 Phase II still relies on a dedicated control channel, so one repeater is dedicated to 9.6 kbps signaling and control. A three repeater P25 Phase II system allows for 4 talkpaths, not 6. A three repeater TETRA system allows for 12 talkpaths.

That's most likely the reason the other systems were not considered. TETRA represents the way to maximize traffic through the system with the greatest efficiency and least amount of money dumped into fixed-end infrastructure (no, I don't sell this stuff).

The parallel to TETRA is OpenSky, with one exception - TETRA has a proven history of success where it's been deployed. Some OpenSky fans might say it actually "works."

As for interoperability, no one ever said "interoperability" could or should be a free-for-all. An agency has the prerogative to contain its internal system. On 700/800 MHz, interoperability can be had on a number of frequencies dedicated to the purpose. It doesn't have to live on the agency's internal system, and an internal-only system does not need to be held hostage to the "I word," especially if it's a heavily worked system just based on day-to-day operations.

There is no reason why an SDR subscriber unit can't accommodate multiple waveforms - that includes TETRA, P25 Phase I, P25 Phase II, and analog.

As for a TETRA scanner, it has to be a very niche product nowhere near worth the return on investment in North America. That doesn't mean the very talented people in the Open Source community couldn't take a swing at it.