Spectrum and Interoperability


In the United States, one needs a license from the FCC to operate a radio outside of two bands: the old Citizens Band (CB) that is 4 Watts at 27 MHz, and the Family Radio Service (FRS) radios that are limited to 1/2 Watt emissions.

In the US, the FCC has provided spectrum (frequencies) for businesses to use in two major bands: 450 - 470 MHz, and 800 MHz. TETRA is authorized in the full 450 - 470 band, and in portions of 800 MHz. TETRA uses a 25 kHz signal that is recognized as "narrow" and efficient by the FCC.


TETRA Licenses

To setup a TETRA base station (central transmitter) in the United States, you need to have a valid license with the FB8 identification. These licenses are available from the FCC, but might be "sold out" in your area. If you are interested in setting up a TETRA network, and are unsure about licenses, please contact us. Nielson Networks works with the FCC, and we are willing to help you find the frequencies required. Remember that each TETRA frequency supplies 4 talk channels, so if you have a present system with a lot of frequencies in use, TETRA may allow you to consolidate them into fewer transmitters. With fewer transmitters, less "plumbing" is required at the tower site.

Despite what you may have heard, the FCC will issue you a new 25 kHz license for TETRA use. If you presently have 25 kHz licenses, they may be converted to the proper digital designation by filling out some forms.


TETRA Integration with other radio systems

Some customers may have an existing radio system that would require a conversion to TETRA over time... the existing radio system is just too large to "switch over". In those cases, or where a permanent link to another system is required, solutions exist to bring the systems together for intgrated opration. Some solutions, such as Piciorgros's DVI-100, can create a TETRA to TETRA bridge. Other solutions, such as Damm's Group Bridge, can link TETRA and analog together. Please contact us, and we may design a solution to integrate TETRA into an existing system.


TETRA Interoperability

One beautiful aspect of TETRA is that the vendors have gotten together for interoperability certifications. This means companies like Damm and Sepura meet with their competition to ensure that the hardware works with each other. An independent group based out of Italy tests the vendor's claims, and publically publishes reports verifying interoperation claims. For more information, including the ability to view products certified to work with each other, please follow this link.