Prince Georges County New 800 Mhz Radio

[paponte0]

State-Of-The-Art Police Towers Going Up In PG
http://www.nbc4.com/news/14517796/detail.html

Groundbreaking Ceremony Held For First 800 Mhz Radio Tower
http://www.co.pg.md.us/Newsroom/PressReleases/PressReleases/news_article14960.asp?h=80n=0

In the press release the County Executive says "This new radio system will have all of the latest technologies available and Prince George’s County will be one of only two jurisdictions in the entire country to have all of the technology. Seattle, Washington is the other jurisdiction. "

What Latest technologies is he talking out? Will the radio be P25?

 

[rfburns]

It seems to imply that it is related to AVL.

 

[allen5565]

Cool! They're either building 15 towers ("...a groundbreaking ceremony for the first of 15 towers to be constructed by the county...") or 18 ("Of the 21 radio towers being used for the system, three are existing towers...") or perhaps as many as 21. Or do they mean the Feds will construct the six additional towers needed to bring the total to 21? I hope their new radio communications turn out less jumbled and confusing than their press release.

Yes, I'd say there is a pretty strong implication of AVL. "As part of this new system, the county will have an Automatic Vehicle Locator program. "

 

[AES-256]

The major difference is that PG's radio system will steer everyone to FDMA or TDMA depending what subscribers radios are using and where they are affiliated on the system. This is going to be a 700MHz system, there were only 12 800MHz pairs left in region 20, 42 and 48 that could be coordinated............not enough for a trunk system for a county of it's size.

I don't know of any other manufacture that has that capability, there could be one.....but I haven't heard of one.

 

[The_B_Chief]

The info I got was that they are using the three existing and adding more to that. The system will also include the AVL’s and hopefully some aluminum foil (thanks Montgomery).

Someone should call Wayne McBride and find out for sure. He’s a good guy and I’m sure is going to get us on a quality system that will work well for us.

 

[ezdropper]

Yup, one of these towers is going literally "in my back yard", in the woods right behind the house. Oh joy...

 

[baybum]

I may have missed this answer earlier...

Will this be a "monitorable" system?

 

[paponte0]

Wow Slvbeard.. your going to have great reception ! Maybe you can just plug your scanner right into that tower

 

[ResQguy]

I may have missed this answer earlier...

Will this be a "monitorable" system?

Not with anything currently available.

 

[dwlipp]

Not with anything currently available.

This is only partially accurate; some talkgroups on the system won't be able to monitored, but others will be.

The system will be capable of P25 Phase II TDMA modulation and some talkgroups will be setup for that configuration; those talkgroups will not be able to be monitored by any scanner that is currently available on the market. Phase II systems are also capable of Phase I modulation and scanners are readily available that support monitoring Phase I systems.

Some talkgroups on the system will be configured for Phase I modulation therefore scanners that are currently available will be able to monitor those talkgroups. The talkgroups that are configured with Phase II modulation will not be able to be monitored with currently available scanners. This is all assuming that encryption is not in play on a given talkgroup because if a talkgroup is encrypted it can't be monitored regardless of the modulation it is configured with.

I strongly suspect that as time goes on that scanner(s) will appear on the market that support Phase II modulation. Right now there isn't much of a market for that capability as there are no Phase II systems in operation. As these systems start getting deployed, and a market develops for scanners capable of listening to them, I would be very surprised if scanners that can monitor them were not available at some point.

Now of course the follow-on question is what talkgroups are going to be configured for Phase I vs. Phase II modulation. I don't know the answer to that question but I do know that some talkgroups will be configured for Phase I modulation to provide more seamless interoperability with other agencies that don't have Phase II capable equipment. I do not know what that breakdown is going to look like but as the system is being implemented I am sure that will become known.

(Not to confuse the issue too much but a Phase II talkgroup will revert to Phase I modulation if a radio affiliates with the talkgroup that is only capable of Phase I modulation. This means that a Phase II resource isn't necessarily always a Phase II resource, but from the perspective of a party interested in monitoring the resource is is essentially not going to be able to be monitored with existing scanners because they don't affiliate with the system [no scanner does or will ever], they only listen to it. So basically if you get lucky you might be able to listen to a talkgroup configured for Phase II modulation if a Phase I user is affiliated with it at the time you are trying to listen to it with a Phase I scanner. Hope this isn't too confusing)

Dallas

 

[jparks29]

I'm curious what they're talking about 'only seattle,wa' has a system like that..... The only thing 'of note' about the king co. system is that it's smartzone, which isn't even that special.....

PG county STILL has 800 Mhz licenses issued to it for it's 800 Mhz EDACS system....


Hell, there aren't even any Phase II PORTABLES out yet, AFAIK. Which was the whole issue to begin with when they were discussing implementing the new system.

BTW, I was the guy who posted the original update about PG replacing radios and trying to put in a digital system... That was about 18 months ago, it's taken them THAT long to actually make a decision, it'll be as long if not longer until things are actually operational..

 

[ka3jjz]

You know it really puzzles me - why didn't PG do like it's neighbor DC did, and reuse the freqs they already had? If I understand the process correctly, it would take a refiling with the FCC to change the type and usage codes to allocate them to a trunk system. As I understand it the infrastructure is in bad shape - but it would have to be torn down in most spots to make way for new towers anyway. Use the 490 mhz freqs for the police, the 800 mhz freqs currently used on the EDACS system for fire. I thought I read somewhere that there were very few 800 mhz freq slots available left for allocation in our region. And we haven't even talked about rebanding yet...73s Mike

 

[baybum]

Short answer? Because it might just possibly make sense.

 

[ka3jjz]

?? What sense? From a purely admin standpoint, they've got to have gotten new 800 mhz allocations from the FCC and coordinated them with the Transition Admin for rebanding. They will, I'm sure, be tearing down or at least replacing the current 490 mhz system (in stages, no doubt). All that costs a bunch of cash; I'm not involved in the purchase of such things, but I'd be willing to wager that refurbishing those UHF sites that can be saved, and tearing down those that can't, would make more sense.

In addition it costs mucho bucks, I'm sure, for the legal junk that has to go on with the FCC and TA to get all those new frequencies coordinated. Reusing what they already had would be cheaper. And let's not forget that the current 800 mhz systems will be impacted by rebanding; the 490 mhz system won't.

Oh yes, I'd forgotten; 'makes sense' and 'government' are practically oxymorons....73s Mike

 

[baybum]

The intention of my last post was to illustrate that your previous post made sense, and that's probably why they didn't go that route, because it makes too much sense.
I was being sarcastic.

 

[TommyP]

The existing 800 Mhz channels in the EDACS systems cannot be fully used in the new system. The existing channels have too many co-channel & adjacent channel conflicts to be used in a countywide simulcast system. Since they were only licensed for single site use, others have implemented systems that now would prohibit this. Some will get use in the DVRS's.

 

[jparks29]

You know it really puzzles me - why didn't PG do like it's neighbor DC did, and reuse the freqs they already had? If I understand the process correctly, it would take a refiling with the FCC to change the type and usage codes to allocate them to a trunk system. As I understand it the infrastructure is in bad shape - but it would have to be torn down in most spots to make way for new towers anyway. Use the 490 mhz freqs for the police, the 800 mhz freqs currently used on the EDACS system for fire. I thought I read somewhere that there were very few 800 mhz freq slots available left for allocation in our region. And we haven't even talked about rebanding yet...73s Mike

That was one of the configurations originally discussed, being that PG borders DC, they'd have direct interop with DC on both PD and fireboard. Interop with AA/MC/etc would've been through patches.

I think it's a piss poor decision, everything will be patched, and transcoded (Phase II <-> Phase I).

The frequencies they're currently licensed for on 800 Mhz are not sufficient to support a countywide trunking system.

I'm surprised they went with /\/\, they've been a GE county forever...

 

[ezdropper]

Construction has begun at the tower in Bowie at southbound 301 just before 50... Was just driving by and noticed it...