What is TETRA signal?

What is TETRA signal?

TETRA is a professional mobile radio and two-way transceiver (walkie-talkie) specification. Formerly known as Trans-European Trunked Radio. TETRA is not to be confused with Tetrapol. Several levels of encryption are offered, however, many networks are unencrypted.

What is TETRA voice?

Description. TETRA uses time-division multiple access (TDMA) with four user channels on one radio carrier and 25 kHz spacing between carriers. In addition to voice and dispatch services, the TETRA system supports several types of data communication.

What frequency does TETRA use?

390 to 400 MHz
TETRA base stations usually transmit in the frequency band 390 to 400 MHz just below the UHF TV band.

How do you listen to a TETRA transmission?

The easiest way to do this is to open SDR# or another program like GQRX and look for them. TETRA signals are continuously broadcasting with a bandwidth of around 25 kHz. In most European countries they can be found at 390 – 470 MHz. In some countries they may be found around 850 MHz or 915 – 933 MHz.

What is trunked mode radio?

A trunked radio system is a two-way radio system that uses a control channel to automatically assign frequency channels to groups of user radios. Instead of assigning a radio channel to one particular user group at a time, users are instead assigned to a logical grouping, a talkgroup.

Do police use Tetra?

Introduction. Terrestrial Trunked Radio (TETRA) is a telecommunications system widely adopted by police and other emergency services around the world with over 300,000 users in Great Britain (https://www.airwavesolutions.co.uk/airwave-in-action/the-emergency-button/).

Can Tetra be decoded?

Now the latest development in TETRA decoders is that a TETRA decoder plugin for the SDR# software has been released. With the plugin turned on you just need to simply tune to a TETRA signal in WFM mode, and you will instantly be decoding the audio.

How do I know if my radio frequency is encrypted?

Feed Provider Since 2012. Others in your area may have a DMR radio or scanner and may be monitoring this system. They would know if it is encrypted or not. You could try asking in your state forum or click on the red and white triangle in the upper right hand corner and ask that this thread be moved.

Can radio frequency be encrypted?

Encryption in radio communications enables secure communication between parties and is achieved by loading the same key into all radios in a group. The key is like a secret number or password that must be known in order to decrypt the call.

What is DSD plus?

DSDPlus is a Win32 application capable of reliably decoding multiple types of digital audio formats commonly found on VHF, UHF and 800 MHz, including (but not necessarily limited to): P25 Phase 1. X2-TDMA – Motorola public safety TDMA system with P25 style signaling (mostly based on DMR)

How is the TETRA air interface encrypted?

To provide confidentiality the TETRA air interface is encrypted using one of the TETRA Encryption Algorithm (TEA) ciphers. The encryption provides confidentiality (protect against eavesdropping) as well as protection of signalling. Currently 4 different ciphers are defined.

How do TETRA mobile stations communicate?

TETRA Mobile Stations (MS) can communicate direct-mode operation (DMO) or using trunked -mode operation (TMO) using switching and management infrastructure (SwMI) made of TETRA base stations (TBS).

How many countries use TETRA in the world?

there were 114 countries using TETRA systems in Europe, Middle East, Africa, Asia Pacific, Caribbean and Latin America. The TETRA-system is in use by the public sector in the following countries. Only TETRA network infrastructure installations are listed.

What are the advantages of TETRA technology?

The main advantages of TETRA over other technologies (such as GSM) are: The much lower frequency used gives longer range, which in turn permits very high levels of geographic coverage with a smaller number of transmitters, thus cutting infrastructure costs.