APCO-25 a joke?

[shmeb]

I've been doing some research on new radio systems, and of course I'm interested in looking at APCO-25 systems, but everything I'm discovering makes me very skeptical of this 'new' technology.

From what I've found, this 'standard' started being developed in the early 90s and still isn't adaquately defined. This causes me lots of concern. First, technology grows at an incredible rate and the capabilities of hardware today grossly outperform anything defined over a decade ago. Also, it's been over 10 years and the standard still isn't fully defined? Sure, we have the CAI down and I believe the first level of trunking, but we still don't know what the 6.25kHz trunking will look like (correct me if I'm wrong).

From what I can see, following the cell phone industry, there seem to be many more better ways to skin the cat rather than following an antiquated 'standard' that was created 10 years ago. Again, correct me if I'm wrong.

And looking at some of the crazy things that have gone on like Moto selling 3600 baud radios that supposedly supported the APCO-25 standard (which is really 9600) frustrates me. From what I've read, the poor folks that bought those radios have a wasted investment. God knows how many other people and companies went through similar issues due to incomplete (or ignored) standards.

Beyond that, I'm having trouble understanding why people would really want APCO-25 trunking systems in a lot of cases. The area I'm in has 800MHz frequencies and we're surrounded by VHF and UHF users. What is an APCO-25 system going to give me? Even if one or two users near me had an 800MHz APCO-25 system, wouldn't it be sufficient for me to have the CAI protocol loaded on my radio to communicate with them if I needed? Again, I'm hesitant to put an antiquated technology in the hands of my users.

Any comments, ideas are appreciated!

 

[grem467]

i find it ironic you refer to ASTRO as antiquated in reference to Analog.


we have a 10 site 800Mhz mixed mode smartzone here and it works FAR better than the old analog systems.

hell even the 4 ASTRO ham repeaters here are the widest coverage machines... i can hit the UHF in ASTRO mode 50 miles away on an HT, cant even tickle it on analog.

if you want a "cell phone" type architecture, then you should consider "OpenSky" by Ma/Com.

 

[shmeb]

I didn't mention ASTRO, just APCO (unless I had a typo).

And my references to cell phone technology are based on technologies more advanced than FDMA which has been exceeded in the cell phone industry many, many years ago. I know that based on the 25kHz bandwidth limitation that we can't use CDMA, but surely TDMA or some other technology has to be better suited for our cramped airwaves than FDMA.

I'll search around for Open Sky. I assume it's a LMR system not a Harmony-type system?

 

[shmeb]

I just saw a comment on another board that surprised me. Does anyone know if this is a real issue?

"Our county has a multi agency communications partnership (MACP). The MACP would not let us use the EFJ radios on the system because they said it would create a safety problem... The example they used: if the system goes down with only motorola radios, it is motorola's problem. If the system goes down with both EFJ and Motorola radios they wouldn't be able to blame motorola if some one got hurt due to a system failure because of the EFJ radios create a possible problem.

To make a long story short, We tried and tried and still had to buy motorola because the MACP would not allow EFJ radios on to the system! "

Part of the alure of APCO-25 is the idea that hopefully the competition on the radios would drive prices down, but if it causes some sort of warranty issue, that negates that idea.

I'd post the link but I'm not sure what the rules are regarding linking other forums...

 

[grem467]

correct, opensky is a TDMA based TRS

 

[N_Jay]

I've been doing some research on new radio systems, and of course I'm interested in looking at APCO-25 systems, but everything I'm discovering makes me very skeptical of this 'new' technology.

You seem to be more than sceptical!
As for your "research", have you asked any questions at www.project25.org or the Project25 yahoo group?

From what I've found, this 'standard' started being developed in the early 90s and still isn't adaquately defined. This causes me lots of concern.

Why the concern?
Most standards continue to evolve over their entire useful life.
Project 25 is no exception.

Would you want Cellular to have stopped with AMPS, USB to have stopped with 1.0? There are thousands of additional examples.

I can not think of one standard that was ever "done"!

First, technology grows at an incredible rate and the capabilities of hardware today grossly outperform anything defined over a decade ago.

I think you are looking at a distorted view of technology. If you take the original goals of Project 25, I don't think you would implement significantly different technology today. Vocoders have improved, but not significantly. Modulation (narrow band) has not changed.

Give me an example of a draw back in the technology choices of Project 25 that could be overcome with some "newer" technology?

Also, it's been over 10 years and the standard still isn't fully defined? Sure, we have the CAI down and I believe the first level of trunking, but we still don't know what the 6.25kHz trunking will look like (correct me if I'm wrong).

This is back to the misunderstanding that a Standard somehow is "finished" before it is used.

You question on 6.25 kHz channels is not overly important as we don't have any 6.25 Khz channels to implement on.

I believe a pure CQPSK system could be built on a 6.25 kHz channel using the existing standards if the equipment was available. (Anyone know for sure)

From what I can see, following the cell phone industry, there seem to be many more better ways to skin the cat rather than following an antiquated 'standard' that was created 10 years ago. Again, correct me if I'm wrong.

Please provide some examples. Specifically how they would apply to LMR.

Cellular standards have been in just as much flux (and maybe more) over the last 10 to 15 years. Name one that is "done".

Most cellular companies have to certify each phone and software version on their network because just meeting the "standard" is not good enough to assure acceptable operation.

And looking at some of the crazy things that have gone on like Moto selling 3600 baud radios that supposedly supported the APCO-25 standard (which is really 9600) frustrates me. From what I've read, the poor folks that bought those radios have a wasted investment. God knows how many other people and companies went through similar issues due to incomplete (or ignored) standards.

You seem to be looking at this whole issue with a very narrow view in terms of both time and technology.

If you looked at the evolution of these systems, you would know why there are 'hybrid' systems that use portions of the standard.

Project 25 was never intended to be a single all inclusive system standard. It is a suite of standards intended to support a wide range of system types.

Beyond that, I'm having trouble understanding why people would really want APCO-25 trunking systems in a lot of cases.

If they are planning on implementing a trunking system on LMR channels, what would you propose at a better solution?

The area I'm in has 800MHz frequencies and we're surrounded by VHF and UHF users. What is an APCO-25 system going to give me?

It provides a standard technology for each of those other agencies to implement.
You may still need multiple radios, one for each band, but that is much better thna several for each band without a standard.

Even if one or two users near me had an 800MHz APCO-25 system, wouldn't it be sufficient for me to have the CAI protocol loaded on my radio to communicate with them if I needed?

Yes! You have got it. Well it does take a bit more like coordination.
(Technology does not fix those issues). But if you are going to have P25 on your field equipment then why NOT implement a P25 system.

Now look at it from the other side?
What are the other agencies on 800 MHz going to "load on their radio" to communicate with you if you go non-standard?

Again, I'm hesitant to put an antiquated technology in the hands of my users.

Well in that case you better stop using FM, Internal Combustion engines, PCs, Cell phones, Pens, Pencils, Eyeglasses, locks with keys, etc!

Any comments, ideas are appreciated!

I would spend some more time researching.
Maybe with some sources closer to the people building and using Public Safety radio systems on a daily basis.

http://www.project25.org/
http://apco911.org
http://www.safecomprogram.gov
http://www.apco911.org/theexchange/index.cgi?index
http://finance.groups.yahoo.com/group/project25
http://finance.groups.yahoo.com/group/PrivateWirelessForum
http://groups.yahoo.com/group/SIEC_group

 

[N_Jay]

I didn't mention ASTRO, just APCO (unless I had a typo).

And my references to cell phone technology are based on technologies more advanced than FDMA which has been exceeded in the cell phone industry many, many years ago. I know that based on the 25kHz bandwidth limitation that we can't use CDMA, but surely TDMA or some other technology has to be better suited for our cramped airwaves than FDMA.

I'll search around for Open Sky. I assume it's a LMR system not a Harmony-type system?

If you are only now coming across OpenSky, you research has been very light.

If you only look at large scale systems using relatively small site separations, then I can see how TDMA seems attractive.

Again, I would suggest you look at the breadth of systems that the Project 25 standards support to understand the technology choices.

 

[jim202]

P-25 systems

The Homeland Security boys have egg on their face over an issue with the okland, CA radio system upgrade. They had sent a letter to Oakland stating that the MA-COM radios are not P-25 compliant. MA-COM said they were and a test was done in Phoenix Arizona.

The important point here is the Motorola system in Phoenix was a new system that has a 9600 baud control channel. MA-COM took and programmed up a number of radios and shared messages and other alerting functions with the other radios on the system. This included Motorola, E.F. Johnson and the MA-COM radios.

Now the Homeland Security people are rewriting the letter to Oakland informing them that the MA-COM radios were now acceptable as P-25 replacements. Joe Noce, the Mesa project manager for the Phoenix-Mesa network said "It worked fine, it's not vaporware, they do have a functioning radio."

This points out that there are other companies other than Motorola that can supply a functional P-25 radio. The big question is do you really need a trunking system for your radio network? There is no single answer to the question. It would depend on a number of issues. The key issue is data being used. The digital network is much better suited to mix both voice and data on the same system.

As for interoperability, that is another big issue. There is no simple answer to it. What I try to get agencies to do is to start using the nation interoperability channels that exist on 800, UHF and VHF now. Program these into all of the radios. On the 800 and UHF channels, program in not just the repeater pairs, but the simplex use of the repeater outputs as well. If enough agencies do this, you start to build in a regional interop system ability with practically no work or equipment investment.

Jim

 

[grem467]

Its a cluster here too, Jim

FL has SLERS, the 800Mhz Provoice with ESK and DES (Statewide)
Jacksonville has FCRS, 800Mhz Astro SmartZone (LEOs are OFB)
Clay County has 800Mhz multinet LTR

to use a cellphone reference, its like having T-mobile on 1900 GSM, and Sprint on 1900 CDMA trying to talk to each others handsets (simplified i know, but still shows how screwed up things can get)

thats the whole reason behind P-25, is to try to get digital to somewhat work together so we dont have the "cellphone" version of TDMA, D-AMPS, GSM, and CDMA protocol nitemare.

guess it didnt help much.

 

[N_Jay]

guess it didnt help much.

Well it would help more if people did not spend all their time rationalizing why is will not help.

Its like religion. No one says theirs is better, they spend all their time why yours is worse!

 

[loumaag]

Re: P-25 systems

The Homeland Security boys have egg on their face over an issue with the okland, CA radio system upgrade. They had sent a letter to Oakland stating that the MA-COM radios are not P-25 compliant. MA-COM said they were and a test was done in Phoenix Arizona.

Hmm, I don't want to hijack this thread but I think I am a little confused by this. Individual radios can be Project-25 compliant. The Oakland system is not, assuming you are talking about Oakland, City of (Public Safety) System. I am not sure what the letter from Homeland Security states, but MA/COM, EF Johnson as well as others do manufacture radios which are P-25 compliant. Obviously MA/COM can make a radio which will work on EDACS and APCO-25 trunking systems, but at what cost? The point is a P-25 compliant radio, which is not also EDACS compliant (which is not part of the P-25 standard) has no chance of communicating on the Oakland system. No matter how MA/COM tries to spin the story, as long as they continue to push their private and proprietary systems, they are just muddying the waters when it comes to inter-agency communications. It is my personal opinion that any entity which elects to go with a non-Project-25 system, should not receive any federal assistance for such a move.

 

[poltergeisty]

Re: P-25 systems

It is my personal opinion that any entity which elects to go with a non-Project-25 system, should not receive any federal assistance for such a move.

And it's my personal opinion that the federal government should not evoke there distasteful pleasings on to the choosing of departmental needs.

Fed ought to focus on the real task of Homeland security. Radio bickering within this apparent "Home Land Security" department and state needs really angers me. I would never mix politics with safety and security based on federal whim. Notice how it's federal agencys that support project-25.

They, Homeland security are hijackers.

PS. I don't like MA/com one bit, but there are many technological ways of interoperability. There should be no harsh punishment to an entity for not playing ball with Home land security.

This is the largest sake of crap I smelled in a long time. This is my personal opinion. Boo!-Poltergeisty :-0

 

[studgeman]

The oakland system is still in developement. One of the requirements was to demonstrate interoperability between manufacturers, hence the Arizona test. M/A Com does make a P25 TRUNKING radio that utilizes the P25 Control signaling. This is not to be mistaken with CAI over EDACS. Kenwood also makes P25 Trunking radio, as well as Motorola and EFJ, Icom is planning a release later this year. The Airzona test was quite extensive in the P25 features it tested, including encryption. For a public safety there are quite a few resources out there which provide FREE technical guidence, the big one being an NIJ funded progam, the regional National Law Enforcement Corrections Technology Centers, nlectc.org, and also the NIJ funded CommTech program for interoperability.

 

[grem467]

M/A Com does make a P25 TRUNKING radio that utilizes the P25 Control signaling. This is not to be mistaken with CAI over EDACS.

are you saying that m/a com got permission from motorola to incorporate their trunking system into their radios?

the only non motorola radio i have ever seen that could do motorola trunking was Standard back in the old type1 days.

 

[studgeman]

Motorola has offered for license free of charge the technology that is used for P25 trunked signalling. It is very similar to Type II. This was part of the agreement with the P25 working group. The actual frame format is published as part of the P25 specs.

On a seprate note, EFJ makes typeII radios.

 

[N_Jay]

M/A Com does make a P25 TRUNKING radio that utilizes the P25 Control signaling. This is not to be mistaken with CAI over EDACS.

are you saying that m/a com got permission from motorola to incorporate their trunking system into their radios?

the only non motorola radio i have ever seen that could do motorola trunking was Standard back in the old type1 days.

Let's repeat the false rumor that P25 trunking is a Motorola system one more time. :evil:

(If you say it often enough, people will start believing you!) :wink:

I also do not think the M/A-COM sells or has sold a CAI on EDACS system. (But why not start another unsubstantiated rumor while we have the time!) :evil:

 

[loumaag]

Let's repeat the false rumor that P25 trunking is a Motorola system one more time. :evil:
(If you say it often enough, people will start believing you!) :wink:

As N_Jay points out, the APCO-25, true Project 25 trunking system has nothing to do with Motorola. It also has nothing to do with M/A-COM. Come-on people, where do you get these ideas?

I also do not think the M/A-COM sells or has sold a CAI on EDACS system. (But why not start another unsubstantiated rumor while we have the time!) :evil:

If anyone knows of an EDACS system that is using P25 CAI modulation, I would like to be pointed toward it.

The Oakland system is not APCO-25 compliant, it can't be, because it is an EDACS system. EDACS systems are by definition not APCO-25 compliant. Let me repeat that once again, EDACS systems are not APCO-25 compliant by definition. The test in AZ established that M/A-COM could produce a radio which could use both systems (EDACS and APCO-25), it did nothing to prove that the system (note I said system not individual radios) was interoperable with other APCO-25 radios.

Now, can M/A-COM install an APCO-25 system? Sure they can, but it won't be EDACS, it would be a Project-25 system and it would use P25 CAI just like every other APCO-25 system there is.

 

[studgeman]

ok first so there can be no misunderstanding. The technology which is known as p25 trunking. the 9600baud control singnaling was developed by Motorola and submitted to the P25 working group. The working group accepted this technology from Motorola and the technology to be incorporated into P25. This technology is freely available without license or IPR agreement with Motorola.

Second, they are building a NEW system in Oakland which will utilize P25 control signaling. The M/A Com radios were tested in p25 trunking mode in both CAI and Encrypted modes. The M/A Com radios TRUNKED on the Motorola built P25 system.

Third, I highly suggest anyone doubting the capabilites of M/A Com or Kenwood to produce a P25 Trunking radio or a radio which operates in CAI mode check with the manufacturer before they post. There are people out there whos job it is to follow these developements, and have contacts across the board when it comes to this topic. All 4 major manufactures now produce P25 CAI and trunking compliant radios[/b]

 

[loumaag]

ok first so there can be no misunderstanding. The technology which is known as p25 trunking. the 9600baud control singnaling was developed by Motorola and submitted to the P25 working group. The working group accepted this technology from Motorola and the technology to be incorporated into P25. This technology is freely available without license or IPR agreement with Motorola.

The technology, no matter who developed it, does not belong to Motorola, hence (as I and other have said); P25 is not Motorola. Also, please get your terminology correct. The only 9600 baud signaling in common usage as a trunking CC is on EDACS systems. The P25 CC is 9.6 bps or 4800 baud if you insist on using the wrong terminology (baud as opposed to BPS).

Second, they are building a NEW system in Oakland which will utilize P25 control signaling. The M/A Com radios were tested in p25 trunking mode in both CAI and Encrypted modes. The M/A Com radios TRUNKED on the Motorola built P25 system.

As I stated, M/A-COM can build P25 trunking radios, as can other manufactures, the point I was making is that an EDACS system is not and cannot be P25 compliant. You are the first person I have ever run into that claims the new Oakland system will be a P25 system.

Third, I highly suggest anyone doubting the capabilites of M/A Com or Kenwood to produce a P25 Trunking radio or a radio which operates in CAI mode check with the manufacturer before they post. There are people out there whos job it is to follow these developements, and have contacts across the board when it comes to this topic. All 4 major manufactures now produce P25 CAI and trunking compliant radios

I don't think I was doubting they could build one, as a matter of fact, if you go back and read what I said, is they certainly can build one. BTW, a P-25 Trunking radio, by definition uses CAI and IMBE Vocoder technology (or else it wouldn't be a P-25 radio.)

Now suppose you provide some hard data explaining that the new M/A-COM installed system in Oakland will be a APCO-25 system and not an EDACS system.