English: A TETRA radio unit as well as an older radio unit in a Swedish (Saab) police car Svenska: En RAKEL-enhet i en svensk polisbil (Photo credit: Wikipedia)
The FCC announced in a report and order today that they are modifying the rules under Part 90 to permit the certification and use of Terrestrial Trunked Radio (TETRA) equipment. Among other changes, Part 90 will now contain Adjacent Channel Power (ACP) limits to enable TETRA equipment to comply.
The TETRA standard was developed by the European Technical Standards Institute (ETSI) and released in 1995; it is widely used within Europe, Asia, Middle East, Africa and South America. It was designed for government agency and emergency services use.
The problem for TETRA in the United States is that TETRA equipment does not observe limits on occupied bandwidth, rather adjacent channel power and unwanted emission limits at different frequency offsets are applied. As a consequence, TETRA equipment will exceed the Part 90 occupied bandwidth limits and emission masks here in the United States. In 2011, the FCC granted TETRA a waiver based on technical information submitted by the TETRA Association asserting that the TETRA equipment provides at least as much protection from interference to other services as any other available technologies.
Thirty days from today’s publication, the TETRA technology will be permitted in the 450-470 MHZ, and 809-824/854-869 MHz band under a modified Part 90. Due to the nature of the trunked technology and it being incapable of monitoring a frequency prior to transmitting, TETRA may be employed only by licensees that are exempt from any monitoring requirements, such as operation above 512 MHz or on channels for which the licensee has exclusive use. Use is prohibited in the 700 MHz public safety spectrum as Congress has specified that Long Term Evolution (LTE) will be the required broadband technology for that segment.
C.F.R. Title 47, Part 90 – Private Land Mobile Radio Services