TETRA vs TETRA2-Basic difference between TETRA and TETRA2
TETRA basically is a ETSI standard. This standard helps establish secure wireless communication for Mobile stations which is stable and undisturbed. TETRA supports various encryption levels to provide secured voice and data communications. This helps provide privacy to the users of the TETRA network. It supports authentication, AIE(Air Interface Encryption) and E2EE(End to End Encryption). This page mentions basic difference between TETRA and TETRA2 releases.
Mobile Stations(MSs) communicate via TETRA standard compliant base stations. MSs can also communicate without basestations in the situations where network is not available or base stations are powered off.
Using TETRA compliant mobile stations connection can be established with other system mobiles or telephones interfaced with PSTN/PBX much like other mobiles. The connection can be either half duplex or full duplex. The major application of TETRA is group calling mode.
TETRA Technology basics
TETRA standard defines air interface specifications, network interface specifications and other services. It has features as outlined in the table-1 below.
|Frequency of operation||About 400MHz|
|space between carriers||25KHz|
|Access Technique||TDMA ; 4 timeslots/carrier|
|Spacing between uplink and downlink||10 MHz|
|Modulation technique employed||pi/4 DQPSK|
|RF carrier data rate||36kbps|
|voice coding rate||7.2 kbps (gross)|
|user data rate per timeslot ; voice+data||7.2kbps (No Error Protection)
4.8Kbps (Low Error Protection)
2.4Kbps (High Error Protection)
|data rate in Packet Data Only mode||36 Kbps gross rate with 4 timeslots|
|Frame Structure||1 TETRA multiframe is made of 18 frames; with total 17 frames are used for voice/data traffic and frame no.18 is used for signalling information. Each frame is basically consists of 4 time slots.|
|Traffic mode of operation||Supports TMO(Traffic Mode Operation) and DMO(Direct Mode Operation) ;
In TMO traffic between Mobile stations is handled via base station. In DMO traffic is handled without base station involvement.
|Call Setup Time||300 ms|
It is upgradable version of the TETRA release-1 mentioned above. TETRA2 is also referred as TEDS i.e. TETRA Enhanced Data Service. High speed data related enhancements are incorporated in this TETRA2 release, hence throughput has been increased.
TETRA2 has following additional features in comparison to its previous release.
• New Modulation and channel coding added, pi/8 D8PSK, 4 level-QAM, 16QAM, 64QAM.
• Various coding rates added
• New channel Bandwidths i.e. 50KHz, 100KHz and 150KHz introduced.
Within the above mentioned bandwidth duration, symbols are distributed on sub-carriers spaced at interval of about 2.7KHz. 50 KHz band includes 16 transmit carrier frequencies, 100 KHz 32 frequencies and so on.
• pi/4 DQPSK with 1 slot -9 Kbps gross bit rate for 25 KHz bandwidth
• pi/4 DQPSK with 4 slots -36 Kbps gross bit rate for 25 KHz bandwidth
• pi/8 DQPSK with 4 slots -54 Kbps gross bit rate for 25 KHz bandwidth
• 4-QAM with 4 slots -supports gross bit rate of 38.4kbps(for 25KHz BW), 76.8kbps(for 50KHz BW), 153.6Kbps(for 100KHz BW), 230.4Kbps(for 150KHz BW)
• 16-QAM with 4 slots -supports gross bit rate of 76.6kbps(for 25KHz BW), 153.6kbps(for 50KHz BW), 307.2Kbps(for 100KHz BW), 460.8Kbps(for 150KHz BW)
• 64-QAM with 4 slots -supports gross bit rate of 115.2kbps(for 25KHz BW), 230.4kbps(for 50KHz BW), 460.8Kbps(for 100KHz BW), 691.2Kbps(for 150KHz BW)
TETRA Radio System Tutorial
Refer TETRA Radio Communication System tutorial covering many aspects of trunking radio system including interfaces, frame structure, standard references etc.
Other Digital Radio and Analog Radio Systems
What is Difference between
FIR filter Vs. IIR filter
difference between FDM and OFDM
Difference between SC-FDMA and OFDM
Difference between SISO and MIMO
Difference between TDD and FDD
Difference between 802.11 standards viz.11-a,11-b,11-g and 11-n
OFDM vs OFDMA
CDMA vs GSM
Bluetooth vs zigbee
Wireless Physical layer standards
Following are some of the useful links for various wireless physical later standards designed to meet
different data rate,coverage and wireless channel requirements.
It covers physical layer standards such as WLAN-11a,11b,11n,11ac,WiMAX-Fixed(OFDM),mobile(OFDMA),GSM,GPRS,CDMA,TD-SCDMA,LTE,WirelessHART and more.
• 11a physical layer
• LTE Physical layer
• fixed wimax physical layer-OFDM
• 11n physical layer
• wirelessHART physical layer
• Physical layer measurements
• 11b physical layer
• Mobile wimax Physical layer-OFDMA
• GSM Physical layer
• GPRS physical layer
• CDMA physical layer
• TD-SCDMA Physical layer
• WCDMA Physical layer
• WCDMA TDD vs FDD physical layer
• WLAN 11ac physical layer