Can Smartzone link 800MHz sites to 450MHz sites?

BigEE · Post by **BigEE** » Thu Aug 11, 2005 5:47 am

Since the zone controller and audio switch link together sites in a smartzone system I wonder if sites of different frequencies cannot be connected just as easily as two sites in the same band. Am I wrong?

Post by **wavetar** » Thu Aug 11, 2005 7:07 am

I don't know of any reason off-hand why it couldn't. Although it sort of defeats the purpose of Smartzone if your radio can't roam between the different frequency sites...

Todd

BigEE · Post by **BigEE** » Thu Aug 11, 2005 7:10 am

The reason I ask is because there are existing SmartZone systems here for 800 and 450, and the big buzz word "interoperability" is being tossed about. I don't see why a single controller and audio switch couldn't route the signals between systems.

RKG · Post by **RKG** » Thu Aug 11, 2005 10:31 am

Huh? The purpose of SmartZone is to enable a subscriber radio to (a) change the "system" (defined for the moment to mean combination of SysID and control channel) on its own and (b) while "roaming" on another system, pull in access to a talkgroup that is native to his home system. At least conceptually, all of the "systems" (as I define them, or "zones" as SZ defines them) should be on the same band, since the assumption is that a single radio could operate on any of them.

What you're talking about hear is really a permanent patch between two separate systems (in any sense of the word), on which no one will ever be roaming, and which are presumably programmed for the same TG IDs. Maybe the hardware and software can be configured to do this, but isn't it way beyond the design concept for SmartZone?

BigEE · Post by **BigEE** » Thu Aug 11, 2005 10:36 am

You are probably right. We are conceptualizing a 450 SmartZone system, and wish to be able to tie in folks on a local 800 SmartNet system for interoperability. Since my understanding is that the Zone Controller and Ambassador switch could care less about actual RF frequency, I ponder whether intersystem calls could be made from a radio on the 450 system to the 800 system.

I can't be the only person who has ever pondered this. There has to be someone out there from a large public safety entity who shares with me the headache of trying to coordinate various divisions operating their own networks. What about OmniLink? Since it connects SmartZone systems, could it do so accross bands? Say an 800 SmartZone system to a 450 SmartZone system?

By the way, thank you for your responses.

Post by **batdude** » Thu Aug 11, 2005 11:04 am

guys, take a look at the washington, dc system.

i believe this is an interconnected 800/UHF system where the FF/para's use UHF and PD is on 800.....

just a thought.

doug

BigEE · Post by **BigEE** » Fri Aug 12, 2005 4:16 am

Thanks Batdude. That was perfect.

Karl NVW · Post by **Karl NVW** » Mon Aug 15, 2005 1:04 pm

The cross-band interoperability suggested is well within the scope of what properly designed SmartZone systems can and do provide.

BigEE · Post by **BigEE** » Tue Aug 16, 2005 4:05 am

Sorry guys, I'm a newbie to Motorola. I've worked for some of their competitors directly but am just learning the M way of doing things.

It appears the controller and audio switch can essentially link SmartNet sites of any band seemlessly. We are looking to extend the future of our public safety system by upgrading it to new technology and this is one idea on the table. I didn't know if it could be done when I first asked but theorized it could be. I've written a proposal based on information each of you and others have provided.

Thank you.

mr.syntrx · Post by **mr.syntrx** » Tue Aug 16, 2005 7:48 am

The Metropolitan Police in London have a VHF site for their helicopter(s) attached to their UHF SZ system.

kb3jkp · Post by **kb3jkp** » Tue Nov 08, 2005 11:19 pm

batdude wrote:guys, take a look at the washington, dc system.

i believe this is an interconnected 800/UHF system where the FF/para's use UHF and PD is on 800.....

just a thought.

doug

just to bring a thread back from the dead,lol

yes.. WASHINGTON,DC's system is exactly like that, FF/EMS on 800 and PD on uhf 460 OBT,IMBE, the COOL thing, is if you have "special" units that need to talk on the 800 system, but are PD units, or vice-versa,fireline officers that need to talk on the PD system,they're interlinked, if you associate a radio on the 800 side to a TG on the 460 side, it'll link the 800 side to the 460 side, multicasting on 460 AND 800, or vice versa, so a 460 mhz PD unit can "talk into" the FD system on 800...

I've been told conflicting information as to the extent of the ability to multicast, some people say ANY talkgroup, some say only "important" talkgroups...

I HAVE seen a 800 portable recieving PD talkgroups, and a UHF radio rx'ing EMS talkgroups.. so I know it works...