what will be next evolution of OSP / MARCS communications?

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dizwiz

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I travel the entire state of ohio for my job and enjoy listening to OSP (accidents, wrong-way drivers headed my way, etc.).

This hobby keeps me very busy entering new freq, talkgroups, rebanding, etc. into my PSR-500.

I am trying to plan for the future. I want to understand what the future holds for OSP communications. If anyone can help me out with the order of 'enhancements' to their communication, let me know. I see the following coming (in this order):

1. Phase 1 but with 9600 BPS control channel
2. Phase 2 TDMA (I will need to upgrade my scanner), 9600 BPS control channel.
3. transfer existing post talkgroups onto MARCS ISP - 700 MHz system?
4. use existing 800 Mhz phase 1 system only for other users (FD, ambulance, etc.)


The thing I am confused about is if they can go TDMA on their current 800 Mhz freq towers.
Or will they all have to migrate to this MARCS ISP - 700 Mhz system to do TDMA.

Anyways, what do you all see happening first?
 

ctpd845

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I travel the entire state of ohio for my job and enjoy listening to OSP (accidents, wrong-way drivers headed my way, etc.).

This hobby keeps me very busy entering new freq, talkgroups, rebanding, etc. into my PSR-500.

I am trying to plan for the future. I want to understand what the future holds for OSP communications. If anyone can help me out with the order of 'enhancements' to their communication, let me know. I see the following coming (in this order):

1. Phase 1 but with 9600 BPS control channel
2. Phase 2 TDMA (I will need to upgrade my scanner), 9600 BPS control channel.
3. transfer existing post talkgroups onto MARCS ISP - 700 MHz system?
4. use existing 800 Mhz phase 1 system only for other users (FD, ambulance, etc.)


The thing I am confused about is if they can go TDMA on their current 800 Mhz freq towers.
Or will they all have to migrate to this MARCS ISP - 700 Mhz system to do TDMA.

Anyways, what do you all see happening first?

I'll answer in the order you laid out.
1. This will happen when they switch to the MARCS-IP P25 system, which I assume will happen sometime in 2014.
2. Phase 2 TDMA could in theroy happen as soon as they switch to the MARCS-IP P25 system.
3. Again this will happen for sure.
4. The original MARCS system will be shut down once everybody is on the new MARCS system, again I think this will happen within the next year.
 

budevans

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I travel the entire state of ohio for my job and enjoy listening to OSP (accidents, wrong-way drivers headed my way, etc.).

This hobby keeps me very busy entering new freq, talkgroups, rebanding, etc. into my PSR-500.

I am trying to plan for the future. I want to understand what the future holds for OSP communications. If anyone can help me out with the order of 'enhancements' to their communication, let me know. I see the following coming (in this order):

1. Phase 1 but with 9600 BPS control channel
2. Phase 2 TDMA (I will need to upgrade my scanner), 9600 BPS control channel.
3. transfer existing post talkgroups onto MARCS ISP - 700 MHz system?
4. use existing 800 Mhz phase 1 system only for other users (FD, ambulance, etc.)


The thing I am confused about is if they can go TDMA on their current 800 Mhz freq towers.
Or will they all have to migrate to this MARCS ISP - 700 Mhz system to do TDMA.

Anyways, what do you all see happening first?

dizwiz,

You seem to be mixing terms and technology. But the short version is your PSR-500 is able to monitor Project 25 systems in Phase 1 mode. Today the only scanner that's Phase 2 capable it the PSR-800. Note: See the Uniden radio forum for information regarding the two new radio's Uniden will be selling next year.

The current legacy MARCS system is a Moto Type II trunk system. The new (still being deployed) MARCS-IP system is a Project 25 trunk system.

The MARCS-IP roll out is roughly at the 1/2 way point as far as infrastructure build out. It will take some time (may be 2 more years to complete the Phase 1 of construction build out (not to be confused with Phase 1 & 2 of P25 transmissions).


1. Phase 1 but with 9600 BPS control channel. 9600 BPS is the data transmission rate for Project 25 trunk systems (both Phase 1 & 2). Not to be confused with the 3600 BPS data transmission rate for Moto Type II trunk systems.

2. Phase 2 TDMA (I will need to upgrade my scanner), 9600 BPS control channel. Your PSR-500 will not be able to monitor Phase 2 TDMA transmissions (but keep reading). The MARCS-IP system is Phase 2 TDMA capable, but so far there are no reports of any one using Phase 2 mode. There are only two reasons to go to Phase 2 mode. Those are 1. FCC mandate to double current frequency utilization (under discussion and could happen in 2017 to 2018 time frame). 2. System over subscription, too many users and not enough frequency's available.

3. transfer existing post talkgroups onto MARCS ISP - 700 MHz system? The construction build out completion will most likely determine when OSP will move to the MARCS-IP system. FYI: The MARCS-IP system is not limited to 700 Mhz. It is being deployed in most locations on 700 Mhz but not all (Lake and Geauga County's for example). The P25 radio's being deployed work on both 700 & 800 Mhz.

4. use existing 800 Mhz phase 1 system only for other users (FD, ambulance, etc.). As I wrote above, the current 800 Mhz MARCS system is a Moto Type II trunking system (Phase 1 & Phase 2 are transmission format designations for P25 systems). The Moto Type II system will be retired when the MARCS-IP Project 25 system is fully deployed. In some places the MARCS-IP system will be on 800 Mhz.

So depending on where you live, it could be several years before the MARCS-IP system is fully deployed. Check out the RR database, here's a link:
Ohio MARCS-IP: Multi-Agency Radio Communications (P25) Trunking System, Various, Ohio - Scanner Frequencies
 
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When they transition to X2-TDMA and then to TDMA, how will this be displayed on our scanners?

Will it show as X2 for X2-TDMA and then T for TDMA?

Happy Holidays
 
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How similar is X2-TDMA to Motortrbo? There was a discussion on another thread that mentioned that they are similar. What about NXDN?
 
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budevans

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No transition to X2-TDMA

When they transition to X2-TDMA and then to TDMA, how will this be displayed on our scanners?

Will it show as X2 for X2-TDMA and then T for TDMA?

Happy Holidays

X2 is not the official Project 25 Phase 2 specification. X2 was Motorola's early offering, it was not approved by the Project 25 group.

Only the official Project 25 Phase 2 spec would be utilized.

Regarding scanners, the PSR-800 does support both X2 and Phase 2 (per reports here on rr). The PSR-800 displays Phase 2 as D2. Since X2 is not an official P25 spec I don't know if the Uniden Scanners will support it.
 

mtindor

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X2-TDMA is irrelevant [as far as MARCS-IP goes] at this point. All signs point to everything that is online already being Phase 2 capable [either upgraded from X2-TDMA or never having been X2-TDMA to begin with].

Any MARCS-IP sites I monitor all report Phase 2 identifiers, not X2-TDMA.

And, just so that I don't confuse anyone, as Bud said there is currently no reported Phase 2 activity on the system. Even if/when that activity is seen, it'll probably ramp up over time.

What the new Uniden scanners will support is all that will be required for MARCS-IP in the foreseeable future.

Mike
 

wa8pyr

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How similar is X2-TDMA to Motortrbo? There was a discussion on another thread that mentioned that they are similar. What about NXDN?

Aside from the fact that all three use the AMBE vocoder from DVSI, there isn't any operational crossover between them. They all use different codecs. P25 is P25, TRBO is more or less compliant with the international DMR standard, and NXDN is... NXDN.
 

wbowery

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I hope this hasn't already been covered, but are MARCS radios purchased five or six years ago compatible with Phase 2? With the state continuing to cut funding to local government, along with the per radio user access fee, I don't see a lot of entities having the funds to purchase new equipment.
 

mdulrich

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I hope this hasn't already been covered, but are MARCS radios purchased five or six years ago compatible with Phase 2? With the state continuing to cut funding to local government, along with the per radio user access fee, I don't see a lot of entities having the funds to purchase new equipment.

I know the radios purchased were full P25 capable and also cover the 700MHz band. Not sure about Phase 2, but if not, that would be a good sign that we won't see much Phase 2 comms for awhile.

Mike
 

wa8pyr

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I hope this hasn't already been covered, but are MARCS radios purchased five or six years ago compatible with Phase 2? With the state continuing to cut funding to local government, along with the per radio user access fee, I don't see a lot of entities having the funds to purchase new equipment.

Some of the earliest radios used by state agencies won't do P25 trunking (XTS3000, Astro Spectra, etc). XTS5000, XTL5000 and later are capable of MARCS-IP but may need a firmware / feature update.

Most of the radios purchased in the last five years or so are probably OK.
 

kf8yk

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X2-TDMA is irrelevant [as far as MARCS-IP goes] at this point. All signs point to everything that is online already being Phase 2 capable [either upgraded from X2-TDMA or never having been X2-TDMA to begin with].

Any MARCS-IP sites I monitor all report Phase 2 identifiers, not X2-TDMA.

The presence of TDMA band plan info in the control channel does not guarantee that the TDMA option has been purchased. All Motorola P25 systems version 7.11 or newer by default will transmit TDMA band plan data, even if the option is not purchased. The only sure fire method to confirm TDMA activity is to log actual TDMA voice channel grants.

I know the radios purchased were full P25 capable and also cover the 700MHz band. Not sure about Phase 2, but if not, that would be a good sign that we won't see much Phase 2 comms for awhile.

The Motorola XTS5000/XTS2500/XTS1500 portables and all XTL series mobiles cannot be upgraded for Phase 2 TDMA, only the newest APX line of radios support TDMA. There is a substantial number of the XTS/XTL radios in use on the MARCS-IP system and until these radios are replaced there's not much advantage to purchasing the TDMA option.

The TDMA option is not cheap, each repeater needs a TDMA software license (p/n: CA013766AA) for $4,000 and a dual mode license (p/n: CA01377AA) if you also want to continue to support Phase I at $12,000. Upgrading the nearly 200 repeaters in the Cuyahoga simulcast site alone would be over $ 3 million.

In addition to the infrastructure costs each APX portable or mobile radio needs a $ 320 TDMA option added to the cost of the radio. I've seen no directives from MARCS compelling users to purchase the TDMA option.
 
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Would a 996XT be able to pick up the new system?

This is a full P25 Trunked Radio System. As long as the 996XT can decode P25 then it should pick-up this system. I know that I can use my PRO-106 to listen. Now just remember that, in Cuyahoga County at least, this system is a Simulcast radio system. This may affect your ability to recieve Ohio's new P25 700/800 MHz Trunked Radio System.

Happy Holidays.

Sent from my Samsung Galaxy Note 2.
 
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