Interoperability Communications
In the Public Safety communications world, interoperability is defined as:
"The ability of public safety service and support providers to talk with each other via voice and data:
- On demand
- In real time
- When needed
- When authorized
It is not the ability to talk to everyone, all of the time."
The VHF Wideband pairs fall in the Marine Band, and can only be utilized in what the FCC calls VHF Public Coast (VPC) areas. There are 33 VPC areas in the inland US, which must not be within 100miles from a major waterway. These channels are limited to 50watts.
Narrowband spacing, such as 12.5kHz and 6.25kHz splits are now normal to accomodate the quickly growing need of more channels in the spectrum. All newly designed radios as of Jan 1st, 2005 looking for FCC acceptance must be 6.25kHz step compatible.
On Jan 1st, 2005, any public safety station on the Interoperability channels, or within 12.5 and 25kHz spacing must be secondary use to any Interoperability traffic. This gives those agencies plenty of time to plan and figure out any options they have. For instance, and agency on 158.730 is a 25kHz channel used for dispatch. If there is a need to use VTac 3 nearby for Interop, then that agency must accept any interference it may receive, and not interfere with the Interop traffic
.