Okay, I'm not a radio programmer so bear with me. What I am is a future end user of a Motorola SmartZone mixed mode (analog/digital) system. I am a volunteer ff in Montgomery Co., PA (Montco).
Montco is in the process of upgrading their seven tower SmartNet system into a 20 tower SmartZone system. There will be two subsystems (east and west) each having 10 towers.
Presently, fire companies in the county (mostly volunteer, some partial paid) operate on both VHF lo and VHF hi. The plan is for the county to be divided into six operational regions for fire service. Each region will have its own fire operations talkgroups for response and initial operations (before switching to a conventional fireground channel). According to information presented recently by the Montco 911 center to area firefighters, there will be three fire regions on each of the SmartZone subsystems (i.e. Regions 1, 2, 3 will be operating off of the west system; regions 4, 5, 6 will be operating off of the east system).
At the presentation, Montco staff stated that in order for a company operating in Region 6 (my area, which borders Region 2) to hear operations in Region 2, field personnel would need tow radios. They gave the example of the OIC monitoring his portable and mobile in order to receive Fire Region 2 and Fire Region 6 traffic.
This concerned a majority of people in the room and I was confused by this statement. I was always under the impression that as long as the SmartZone system was programmed for particular talkgroups to be active on all sub-systems, then you'd be able to hear traffic on said talkgroup if it was in the radio scan plan. I asked if this was correct during the presentation and was told no and that we would need to monitor two 800 radios to hear the two subsystems. No matter whether I'm right or wrong, if someone could provide a somewhat detailed explanation of how the talkgroup programming and radio affiliation works in SmartZone systems (or point me to a reference), it would be appreciated.
The big concern voiced at the meeting was that if you miss a neighboring company get dispatched (we'll have a single talkgroup rebroadcasting the voice traffic from our older dispatch channels; there are 6 dispatch channels right now, 3 each VHF-lo and VHF-hi) and that neighboring company is in a different Fire Region (on a different sub-system), you'll never hear their operations. This could be problematic from a resource planning point of view.
Maps to help visualize what I'm talking about can be found here:
http://www.montcopa.org/EOC/EDS/ by clicking on the Radio Project button. I am a member of Station 46 and was thinking of us being able to monitor Station 53 and vice versa since we are mutual aid companies.
If I haven't explained myself well enough, let me know.
End User Question Regarding SmartZone Operations
Moderator: Queue Moderator
-
benrussellpa
- Posts: 4
- Joined: Sun Dec 16, 2001 4:00 pm
For this, I believe it depends on how the zone controller is programmed. I'm not a trunking expert - so I won't claim that what I say is the gospel, but this should answer your question.
For this explanation we'll use (this you should be able to figure out):
1-W
2-W
3-W
4-E
5-E
6-E
So lets say 2-W and 4-E are neighbors. You run mutual aid - the whole nine yards.
If they are splitting the system into two completly different trunked systems that are NOT interconnected - the statement that you can't listen to both without a seperate radio will probably hold true. Why they would do this would baffle me, so I'm going to assume it's the who system, split into 2 zones - 3 districts / zone.
Your radios should be able to travel into the W zone and hear E talkgroups. When you power on the radio it should affiliate with the tower saying I'm radio 123456. Controler goes - OK - is it authorized? yes - ok - here's what it's allowed to do. 123456 can see 1,2,3 W, but if it's one the W network, it can't see E talkgroups. If it flips over, it'll continue to get E talkgroups and hear W talkgroups. This is so that you can travel out of your area and still hear your home traffic and talk to your home dispatcher. This is probably how they are going to program the system.
Now - They probably decided this after a study was done on network utilization. They probably have a bank of frequencies that they ran utilization tests on. They determined that if they had a complete simulcast system of the whole network throughout the county the traffic on the system would outweigh the channel capacity, so dividing it made the most sense.
So to put it back into understandable english - and I think the above is a little convoluted - but might make sense:
They divided it into two zones. Radios in their respective zones can hear traffic from those zones only. If your radio affiliates with a different zone's tower, then your talkgroups would end up patched onto that tower (or simulcast group) for the duration of affiliation. Because a west side radio might not always be affiliated on the east side, if your portable was affiliated with the east side, it would not hear the west traffic. IF by chance a west radio ended up on the east system - you would run the chance of hearing the traffic.
So in short - unless they program the system differently - your probably going to be stuck in one way or another.
IF you program your radio by yourself - which would require system keys, legal versions of the software, rib, cables, and some know how, valid radio ID, talkgroup listing - 3/4 of which your not going to be able to obtain through official channels unless your VERY lucky - this probably isn't going to happen easily.
If you happen to work around the above paragraph, you an set your radio to affiliate on PTT to a specific site, which would mean that you could set your radio to always affiliate to an east side tower on a certain zone.
There are a lot of safety issues that I could go into with the above, but I won't go into them.
I'm hoping RKG/Wavetar and other trunking gurus will kinda help clean up my somewhat messy yet hopefully understandable explanation.
-Alex
[note: this was moved into System Infrastructure due to the fact it matches it better.
If the poster could give us more information - you mentioned digital/analog - so I am also assuming this is a 3600 trunked system - not full APCO25 9600baud trunking (only digital) I think it would help us better answer your questions. Also - what kind of portables/mobiles would you be using.]
For this explanation we'll use (this you should be able to figure out):
1-W
2-W
3-W
4-E
5-E
6-E
So lets say 2-W and 4-E are neighbors. You run mutual aid - the whole nine yards.
If they are splitting the system into two completly different trunked systems that are NOT interconnected - the statement that you can't listen to both without a seperate radio will probably hold true. Why they would do this would baffle me, so I'm going to assume it's the who system, split into 2 zones - 3 districts / zone.
Your radios should be able to travel into the W zone and hear E talkgroups. When you power on the radio it should affiliate with the tower saying I'm radio 123456. Controler goes - OK - is it authorized? yes - ok - here's what it's allowed to do. 123456 can see 1,2,3 W, but if it's one the W network, it can't see E talkgroups. If it flips over, it'll continue to get E talkgroups and hear W talkgroups. This is so that you can travel out of your area and still hear your home traffic and talk to your home dispatcher. This is probably how they are going to program the system.
Now - They probably decided this after a study was done on network utilization. They probably have a bank of frequencies that they ran utilization tests on. They determined that if they had a complete simulcast system of the whole network throughout the county the traffic on the system would outweigh the channel capacity, so dividing it made the most sense.
So to put it back into understandable english - and I think the above is a little convoluted - but might make sense:
They divided it into two zones. Radios in their respective zones can hear traffic from those zones only. If your radio affiliates with a different zone's tower, then your talkgroups would end up patched onto that tower (or simulcast group) for the duration of affiliation. Because a west side radio might not always be affiliated on the east side, if your portable was affiliated with the east side, it would not hear the west traffic. IF by chance a west radio ended up on the east system - you would run the chance of hearing the traffic.
So in short - unless they program the system differently - your probably going to be stuck in one way or another.
IF you program your radio by yourself - which would require system keys, legal versions of the software, rib, cables, and some know how, valid radio ID, talkgroup listing - 3/4 of which your not going to be able to obtain through official channels unless your VERY lucky - this probably isn't going to happen easily.
If you happen to work around the above paragraph, you an set your radio to affiliate on PTT to a specific site, which would mean that you could set your radio to always affiliate to an east side tower on a certain zone.
There are a lot of safety issues that I could go into with the above, but I won't go into them.
I'm hoping RKG/Wavetar and other trunking gurus will kinda help clean up my somewhat messy yet hopefully understandable explanation.
-Alex
[note: this was moved into System Infrastructure due to the fact it matches it better.
If the poster could give us more information - you mentioned digital/analog - so I am also assuming this is a 3600 trunked system - not full APCO25 9600baud trunking (only digital) I think it would help us better answer your questions. Also - what kind of portables/mobiles would you be using.]
The Radio Information Board: http://www.radioinfoboard.com
Your source for information on: Harris/Ma-Comm/EFJ/RELM/Kenwood/ICOM/Thales, equipment.
Your source for information on: Harris/Ma-Comm/EFJ/RELM/Kenwood/ICOM/Thales, equipment.
Alex: close.
A SmartZone system uses "zones" that are, in fact, different "systems" (i.e., they do not share the same combination of SysID and control channel(s)). However, the "zones" (or "systems") are linked by the overall controller.
When a radio is turned on, it attempts to affiliate with one of the "zones," and after doing so, it listens the control channel for that zone until it loses it, at which point it searches for another zone's control channel. At any given point in time, the radio can only send ISWs to the zone on which it is affiliated, and it can only react to OSWs sent by the system whose control channel it is listening to.
When a radio affiliates, it identifies itself to the controller as present, AND it tells the controller what talkgroup it has "selected" in its radio. (That is why a SmartZone radio transmits every time you move the channel selector.) (And it also why, if you are not an authorized user and are attempting to monitor only, you have to treat the different zones as completely different systems, and switch between them manually.)
Talkgroups on a system (using the term broadly) fall into three groups. "Home (only)" talkgroups will be heard and may transmit only via radios that have affiliated to the "zone" to which those talkgroups are "homed." These talkgroups are as foreign to other "zones" as they are to completely different systems.
"Statewide" or fully simulcast talkgroups will be rebroadcast by all zones at the same time (albeit on different voice channels on different zones). This tends to be very burdensome to infrastructure, since it consumes a voice channel on Zone B for traffic every time a radio in Zone A presses the key on that talkgroup. Statewide talkgroups have to be very limited.
"SmartZoned" talkgroups are talkgroups that will be repeated on the home zone AND will also be repeated on any other zone on which someone has affiliated on that talkgroup. How many talkgroups you can mark "SmartZoned" depends on system voice channel capacity and terrain topography.
(For instance, on the MSP system, t/g "C PTL 1" (the first road channel for the middle-of-the-state zone) is "SmartZoned" into the A Troop (north eastern part of the state) system. However, there is virtually always a C Trooper whose radio gets a far better shot on an A Troop control channel than on a C Troop control channel, with the result that C PTL 1 traffic is carried on the A Troop system virtually all of the time. This is not what was intended.)
Now let's modify your model a bit. We have two zones, East and West. We have channels E1, W1, E2, W2 and SW.
E1 and W1 are SmartZoned. E2 and W2 are home only. SW is statewide.
A radio in the east zone affilliates on SW, and the only other radios aff'd on that talkgroup are also in the east zone. He PTTs. His ISW for a group call on SW will cause an OSW implementing channel grant to go out on that talkgroup for the East Zone, and another OSW making a channel grant for that talkgroup will go out in the West Zone (even though no one in the West Zone is listening). In the east zone, the voice will be carried on channel X from all east zone sites), and in the west it will be carried on channel Y.
Now we have a guy who is in the east zone and affiliated on E1. He drives over the mountain and his radio loses the east control channel, so it finds the west control channel, affiliates on the west zone, and tells the west zone controler that it has selected E1. A trooper in the east zone now keys on E1. The ISW is processed the normal way in the east zone, and because the overall controller knows that it has a radio affiliated in the west zone on a talkgroup that is SmartZoned into west, it will cause an OSW to go out on the west control channel and will carry the audio input by the east zone trooper. So our wandering hero hear's his pal back east, and, indeed, he can key and respond to him.
A couple of cars back is another east zone trooper, but his radio was set to E2. E2 is home zone only. When his radio loses the east zone controller, it switches to the west zone, but if traffic is initated on E2 back in the east zone, he will hear nothing because the overall controller will not link zones on a home zone only talkgroup. If tail end Charlie tries to key up on E2, his radio will buzz.
So, you might say, the solution for the mutual aid channels is to make them all SmartZoned into both zones. Well, yes, but two potential problems. The first is that the system has to have enough voice channel capacity to handle the load. The second is that you be sure that the voice repeaters in the two zones are far enough apart (geographically and in terms of spectrum) that their simultaneous keyup doesn't cause problems. Doable, but not as simple as some folks have thought.
The trouble with long-winded answers is that you sometimes lose track of the question, but I think I have addressed it?
A SmartZone system uses "zones" that are, in fact, different "systems" (i.e., they do not share the same combination of SysID and control channel(s)). However, the "zones" (or "systems") are linked by the overall controller.
When a radio is turned on, it attempts to affiliate with one of the "zones," and after doing so, it listens the control channel for that zone until it loses it, at which point it searches for another zone's control channel. At any given point in time, the radio can only send ISWs to the zone on which it is affiliated, and it can only react to OSWs sent by the system whose control channel it is listening to.
When a radio affiliates, it identifies itself to the controller as present, AND it tells the controller what talkgroup it has "selected" in its radio. (That is why a SmartZone radio transmits every time you move the channel selector.) (And it also why, if you are not an authorized user and are attempting to monitor only, you have to treat the different zones as completely different systems, and switch between them manually.)
Talkgroups on a system (using the term broadly) fall into three groups. "Home (only)" talkgroups will be heard and may transmit only via radios that have affiliated to the "zone" to which those talkgroups are "homed." These talkgroups are as foreign to other "zones" as they are to completely different systems.
"Statewide" or fully simulcast talkgroups will be rebroadcast by all zones at the same time (albeit on different voice channels on different zones). This tends to be very burdensome to infrastructure, since it consumes a voice channel on Zone B for traffic every time a radio in Zone A presses the key on that talkgroup. Statewide talkgroups have to be very limited.
"SmartZoned" talkgroups are talkgroups that will be repeated on the home zone AND will also be repeated on any other zone on which someone has affiliated on that talkgroup. How many talkgroups you can mark "SmartZoned" depends on system voice channel capacity and terrain topography.
(For instance, on the MSP system, t/g "C PTL 1" (the first road channel for the middle-of-the-state zone) is "SmartZoned" into the A Troop (north eastern part of the state) system. However, there is virtually always a C Trooper whose radio gets a far better shot on an A Troop control channel than on a C Troop control channel, with the result that C PTL 1 traffic is carried on the A Troop system virtually all of the time. This is not what was intended.)
Now let's modify your model a bit. We have two zones, East and West. We have channels E1, W1, E2, W2 and SW.
E1 and W1 are SmartZoned. E2 and W2 are home only. SW is statewide.
A radio in the east zone affilliates on SW, and the only other radios aff'd on that talkgroup are also in the east zone. He PTTs. His ISW for a group call on SW will cause an OSW implementing channel grant to go out on that talkgroup for the East Zone, and another OSW making a channel grant for that talkgroup will go out in the West Zone (even though no one in the West Zone is listening). In the east zone, the voice will be carried on channel X from all east zone sites), and in the west it will be carried on channel Y.
Now we have a guy who is in the east zone and affiliated on E1. He drives over the mountain and his radio loses the east control channel, so it finds the west control channel, affiliates on the west zone, and tells the west zone controler that it has selected E1. A trooper in the east zone now keys on E1. The ISW is processed the normal way in the east zone, and because the overall controller knows that it has a radio affiliated in the west zone on a talkgroup that is SmartZoned into west, it will cause an OSW to go out on the west control channel and will carry the audio input by the east zone trooper. So our wandering hero hear's his pal back east, and, indeed, he can key and respond to him.
A couple of cars back is another east zone trooper, but his radio was set to E2. E2 is home zone only. When his radio loses the east zone controller, it switches to the west zone, but if traffic is initated on E2 back in the east zone, he will hear nothing because the overall controller will not link zones on a home zone only talkgroup. If tail end Charlie tries to key up on E2, his radio will buzz.
So, you might say, the solution for the mutual aid channels is to make them all SmartZoned into both zones. Well, yes, but two potential problems. The first is that the system has to have enough voice channel capacity to handle the load. The second is that you be sure that the voice repeaters in the two zones are far enough apart (geographically and in terms of spectrum) that their simultaneous keyup doesn't cause problems. Doable, but not as simple as some folks have thought.
The trouble with long-winded answers is that you sometimes lose track of the question, but I think I have addressed it?
Phew - I guess those lunches have paid off 
RKG - you mind adding in the definitions for
OSW
ISW
I can't think of something that matches up.
You said what I was trying to get at, you just seem to have a better way of illustrating it, and of course, correcting me where needed. Always something learned.
-Alex
RKG - you mind adding in the definitions for
OSW
ISW
I can't think of something that matches up.
You said what I was trying to get at, you just seem to have a better way of illustrating it, and of course, correcting me where needed. Always something learned.
-Alex
The Radio Information Board: http://www.radioinfoboard.com
Your source for information on: Harris/Ma-Comm/EFJ/RELM/Kenwood/ICOM/Thales, equipment.
Your source for information on: Harris/Ma-Comm/EFJ/RELM/Kenwood/ICOM/Thales, equipment.
-
benrussellpa
- Posts: 4
- Joined: Sun Dec 16, 2001 4:00 pm
I'm hoping RKG/Wavetar and other trunking gurus will kinda help clean up my somewhat messy yet hopefully understandable explanation.
-Alex
[note: this was moved into System Infrastructure due to the fact it matches it better.
If the poster could give us more information - you mentioned digital/analog - so I am also assuming this is a 3600 trunked system - not full APCO25 9600baud trunking (only digital) I think it would help us better answer your questions. Also - what kind of portables/mobiles would you be using.]
Yes, this is a 3600 baud system. The ems and police who are already on the original Smartnet system are analog users (except for those PD's upgrading their radios to digital, as the SmartZone system comes on line, for the encryption it will allow). All fire service will be digital. Portables recommended for use include the XTS-2500 portable, XTS-5000 portable, and the Asto Spectra mobile. Literature for these radios (like you guys need that), as well as numerous maps (including fire station locations, towers sites, east/west system dividing line, proposed fire regions, etc) can be found on the County 911 center's website. http://www.montcopa.org/EOC/EDS
Ben
RKG's explanation is far better than I could have put forward. Our SmartZone system here in Nova Scotia is truly that, SmartZone only. All talkgroups are Smartzoned, there is no Home or Simulcast talkgroups at all. It is comprised of two seperate systems (ID 6939 & ID 6D19), but they are linked together via Embassy Audio Switch, making it a Smartzone-Omnilink system. 68 sites to cover little old Nova Scotia, giving us plenty of channel capacity to run things this way.
Todd
Todd
No trees were harmed in the posting of this message...however an extraordinarily large number of electrons were horribly inconvenienced.
Welcome to the /\/\achine.
Welcome to the /\/\achine.