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SCPD

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I visited LA about a year ago and this question has been nagging me ever since. Why doesn't the LAPD and LA county invest in a joint digital trunked system, like a moto smartzone. It just seems that the system they are using is outdate and cumbersome. Are they any plans in the future to upgrade to a different system?
 

BaLa

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SCPD

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Those Systems are VERY Expensive
And a lot of times they end up over budget and or under performing anyway.

MotorolaSolutions - About Us - Newsroom - Press Releases - LA-RICS Selects Motorola Solutions to Develop Interoperable Public Safety Radio System for the Los Angeles County Region


Should be happy they have a simple system there for now.
Who knows they may encrypt everything in the future, unfortunately more and more are going that route.
I agree with all aspects of your post. Especially the encryption aspect..cant agrue with that. They are expensive but I was still kinda shocked that they weren't a smartzone system or the like. Here in South Dakota we have a state wide system VHF p25 smartzone system with 50 some sites and only have 800,000 people in our state. With the greater tax base in So Cal I'm hoping they could afford it lol
 

pepsima1

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Riverside Co use to be fully wide open in the clear and now the whole county went to a new phase II system and went fully encrypted
 

kayn1n32008

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bwca44 said:
... Here in South Dakota we have a state wide system VHF p25 smartzone system...
Be happy it is on VHF...
 
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kenjicam

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All I can say is LARICS will be coming to a LA Sheriff's station near you. It will most likely be another couple of years before you see all LASD traffic moved onto this future system.
From what I have heard LAPD, LAFD, and LACoFD will keep using what they got and will most likely use LARICS for Admin traffic. I'm sure they will all eventually move to LARICS, but LASD will be the first to go.
 

SCPD

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I agree with all aspects of your post. Especially the encryption aspect..cant agrue with that. They are expensive but I was still kinda shocked that they weren't a smartzone system or the like. Here in South Dakota we have a state wide system VHF p25 smartzone system with 50 some sites and only have 800,000 people in our state. With the greater tax base in So Cal I'm hoping they could afford it lol
The difference between South Dakota and southern California from the aspect of radio is about as large as it can be. There are about 5 times the population of all of South Dakota in the City of Los Angeles, just one of 88 cities in L.A. County, which has 10 million people. The continuous urban area that L.A. County is a part of, with Ventura, Orange, Riverside, San Bernardino and San Diego Counties, a megalopolis is what I call it, is 17.5 million people. Mix in the L.A. Airport, one of the busiest seaports in the world, manufacturing, petroleum refining, high rises, heavily visited beaches and amusement parks, the busiest freeway system in the world and the most volatile wildland fire environment in the world; and what you have is an extremely complex RF environment to deal with. Frequency licensing is not easy in this environment.

Just one unit of Cal Fire's 21 operational units, especially in southern California, has far more activity than South Dakota's Wildland Fire Division. Statistics for other agencies in the area are very high and radio systems have to have many more frequencies than less active agencies in rural areas.

Terrain is a factor as well. The mountains surrounding this megalopolis are steep in comparison with what South Dakota has. L.A. County is split by the San Gabriel Mountains, and you don't realize how rugged they are until you try to walk cross country in them, something I've done a few times fighting fire. You can't put up a tower or two in L.A. County and expect to cover much territory.

Then the seismic factor comes in. Communications systems need to be redundant and physical facilities hardened to withstand earthquakes. Not enough work has been done in that area, but quite a bit has been accomplished.

L.A. County is one of the limited number of areas that were granted frequencies in the 470 - 512 MHz range, the so called UHF-T band. The U.S. Congress voted to eliminate land mobile radio use in the band. I can't count how many agencies in southern California have most, and some all, of their frequencies in that band. There has been far more work on interoperability and mutual aid systems using UHF frequencies than you might think. Fire departments with wildland fire incidents in their jurisdictions have VHF-High radios (mobiles and handhelds) as that band is the nearly universal for wildland firefighting. There are fixed and portable patching or cross over systems as well.

The complexity and expense of putting in a regional trunked radio system is mind boggling. Some members of Radio Reference don't believe it can be done. Only time will tell. I think it can be done, but I'm not holding my breath.
 

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To continue Exsmokey's comment above, when the 482-488 MHz spectrum was opened to L.A. area public safety in the mid-1980s, there was a comprehensive regional planning effort to provide frequencies to as many agencies as possible. In order to do that, by agreement the participating agencies (which included LAPD, LAFD, LAcoFD, LASD, Santa Monica, Beverly Hills, Montebello, Burbank, Glendale, Pasadena, and more) limited their radio signal coverage area so that channels could be reused or the 12.5 kHz adjacent channel could be assigned to another agency at physical spacings much closer than previously done. [1]

As a result, LAPD has built conventional infrastructure that serves well in the particular areas of L.A. that a given channel has to cover, and is very fault-tolerant to repeater failures (just switch to simplex). Moving that to a trunked system can be done, but the cells of the trunked system would have to be engineered to provide the same level of service as the existing conventional system (which means larger or additional sites, new towers, etc.) at an even greater cost.

[1] The success of that planning effort was the FCC's model for the creation of 55 Regional Planning Committees nationwide a couple of years later when the NPSPAC portion of the 800 MHz band was allocated to public safety, and again when the 700 MHz band was allocated to public safety.
 

902

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Let me further expound on the idea of trunking that Don and Exsmokey stated. Trunking is built on the premise that there are unused or under-utilized resources within a system. In an extremely busy network that can go non-stop, there is little advantage to trunking because there's nothing to trunk.

Trunking also requires symmetry. In order to use the resources effectively, those smaller sites that cover specific zones, much like NYPD has set up, would need to be part of the larger system. That means adding all of those transmitters and receivers to every single site. That drives the cost exponentially. Newer is not always better.

Finally, T-Band is a matter of serious contention these days. A handful of (self appointed) public safety "representatives" bargained it away to accept the Upper D Block on 700 MHz for the public safety broadband initiative legislated in the "Middle Class Tax Relief and Job Creation Act of 2012." Congress expects the FCC to reclaim and auction it within about an 8 year time frame. The prevailing thought is that the users can migrate to 700 MHz and Radio over LTE emulation apps (that currently have no simplex capability... or network, for that matter). (Moreover, the giveback requirement was so poorly thought out that it didn't take into account business licensees or TV broadcasters.) Reality is that nothing moves that fast in the public sector, even if it were feasible. Ever. So that's a struggle as well.

The major cities have had a lot of time to evolve their systems to tailor-fit their needs. You might notice that some cities have diverse conventional systems - AND have one or more trunked radio systems serving it, as well.

Now, about VHF trunking - some things are about as appropriate as breeding dogs and cats. VHF trunking is like that. Just because it "could" be done never means that it actually "should," especially in areas where there are shortfalls in frequency resources.
 
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