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    Trunking Radio System TETRA

    Uploaded by

    Salahuddin Mughal
    TETRA (Terrestrial Trunked Radio) is an digital trunked radio system standard used worldwide for public safety networks, utilities, transportation and government users. It uses TDMA technology within 25 kHz channels to provide 4 voice or data slots, allowing better spectral efficiency than analog systems. TETRA supports both trunked and direct mode operations, with fast call setup times, security features and open standards to ensure interoperability between different vendors. It has become the dominant professional mobile radio system internationally due its cost-effectiveness and ability to meet the critical communication needs of emergency responders and mission-critical groups.

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    Trunking Radio System TETRA

    Uploaded by

    Salahuddin Mughal
    148 views21 pages
    TETRA (Terrestrial Trunked Radio) is an digital trunked radio system standard used worldwide for public safety networks, utilities, transportation and government users. It uses TDMA technology within 25 kHz channels to provide 4 voice or data slots, allowing better spectral efficiency than analog systems. TETRA supports both trunked and direct mode operations, with fast call setup times, security features and open standards to ensure interoperability between different vendors. It has become the dominant professional mobile radio system internationally due its cost-effectiveness and ability to meet the critical communication needs of emergency responders and mission-critical groups.

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    TETRA (Terrestrial Trunked Radio) is an digital trunked radio system standard used worldwide for public safety networks, utilities, transportation and government users. It uses TDMA technology within 25 kHz channels to provide 4 voice or data slots, allowing better spectral efficiency than analog systems. TETRA supports both trunked and direct mode operations, with fast call setup times, security features and open standards to ensure interoperability between different vendors. It has become the dominant professional mobile radio system internationally due its cost-effectiveness and ability to meet the critical communication needs of emergency responders and mission-critical groups.

    Copyright:

    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    148 views21 pages

    Trunking Radio System TETRA

    Uploaded by

    Salahuddin Mughal
    TETRA (Terrestrial Trunked Radio) is an digital trunked radio system standard used worldwide for public safety networks, utilities, transportation and government users. It uses TDMA technology within 25 kHz channels to provide 4 voice or data slots, allowing better spectral efficiency than analog systems. TETRA supports both trunked and direct mode operations, with fast call setup times, security features and open standards to ensure interoperability between different vendors. It has become the dominant professional mobile radio system internationally due its cost-effectiveness and ability to meet the critical communication needs of emergency responders and mission-critical groups.

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    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    of 21

    TETRA (TERRESTRIAL TRUNKED

    RADIO)

    123seminarsonly.com
    WHAT IS TETRA
    • * Advanced Digital Radio Communications System for
    Public Safety Services, Utilities, Transport, Local
    Government, Military

    • * Operational throughout Europe, Asia-Pacific, Africa,


    South America and Middle East

    • * Standard promoted by ETSI

    • * Multi-vendor supply / interoperation


    123seminarsonly.com
    FREQUENCY RANGE
    • 1. 400 MHz

    • 380 - 400 MHz for public safety systems

    • 410 - 430 MHz for commercial applications

    • 2. 800 MHz for commercial applications

    • standard based on TDMA technology


    with 4 timeslot and 25 kHz band

    123seminarsonly.com
    TETRA is superior PMR technology
    •Individual and group communications
    •Direct mode communication between radios
    •Packet data and fast data transfer services
    •Over-the-air programming of radios
    •Frequency economy
    •Fast call set-up time
    •Security features

    123seminarsonly.com
    To ensure an open multivendor market, TETRA
    specifies the following essential interfaces:

    • Air Interface ensure the interoperability of terminal equipment


    from different manufacturers.

    • Terminal Equipment Interface (TEI) facilitates the independent


    development of mobile data applications.

    • Inter-System Interface (ISI) allows the interconnection of TETRA


    Networks from different manufacturers.

    • Direct Mode Operation (DMO) guarantees communication


    between terminals also beyond network coverage .

    123seminarsonly.com
    TECHNOLOGY OF TETRA

    TETRA

    FDMA TDMA
    123seminarsonly.com
    TETRA TDMA
    •4:1 TDMA (Time Division Multiple Access)
    25 kHz carrier spacing
    •Digital modulation, /4 DQPSK at 36 kbits/s
    •Speech calls use one channel
    •Data calls can use up to 4 channels ( Data transfer
    rates up to 7.2 kbit/ s per channel)

    Four user channels interleaved


    into one 25 kHz carrier

    123seminarsonly.com
    Air Interface - TDMA Illustrated
    Hyperframe (61.2s)

    1 2 3 4 5 60

    Multiframe (1.02s)
    1 2 3 4 17 18
    control
    frame
    TDMA frame (56.67ms)

    1 2 3 4
    Time slot (14.167ms)
    = 510 modulating bits

    1 2 3 4 5 508 509 510

    123seminarsonly.com
    PHASE SHIFT KEYING PROCESS
    010

    011 001

    45
    100 000

    101 111

    123seminarsonly.com
    110
    WIRELESS CHANNEL AT TRANSMITTER
    END

    PROPAGATION
    CHANNEL

    ENCODER MODULATOR RF/IF STAGES

    123seminarsonly.com
    WIRELESS CHANNEL AT RECIEVER END
    PROPAGATION
    CHANNEL

    RF/IF
    STAGES
    DEMODULATOR DECODER

    123seminarsonly.com
    7 CELLULAR CONCEPT
    4 ARFCN IN ONE CELL
    4*7=28 ARFCN

    123seminarsonly.com
    HANDOVER PROCESS

    123seminarsonly.com
    TETRA Traffic case - simplex calls
    • Simplex Calls
    – Mobile is either transmitting or receiving
    – Requires operation of PTT switch (Push To Talk)
    – Talk time is usually limited, typically 1 minute maximum
    – Group calls are always
    simplex

    123seminarsonly.com
    TETRA Traffic case - duplex calls
    • Duplex Calls
    – Mobile is transmitting and receiving (like GSM phone call)
    – Does not require holding PTT to continue transmission
    – Recommended for making measurements - no talk timer
    – Phone calls are usually but not always duplex

    123seminarsonly.com
    TETRA Traffic case - Group call
    • Group call
    – A call between more than 2 parties
    – Call is always simplex, direct set-up
    – Only possible if one or more groups have been attached

    123seminarsonly.com
    TETRA is the Cost - Effective
    Technology
    Four-channel TDMA gives Trunking technology supports
    excellent spectrum economy - controlled use of shared
    4 channels in one 25 kHz networks
    carrier

    TDMA makes cost-


    effective Base Stations

    123seminarsonly.com
    TETRA INFORMATION
    INFORMATION IMPORTANCE

    Exrtremly
    urgent TETRA

    Highly GSM
    important

    DECT
    routine

    TIME CRITICALLY OF CALL SET UP


    Non urgent Urgent Immediate
    <1 min 123seminarsonly.com
    <10 sec <1s
    Difference between GSM and TETRA System

    GSM System TETRA System


    Designed for public cellular Designed for professional mobile
    telephony. radio applications.
    Based on Duplex & point to point Based on simplex, semi duplex,fill
    communication. duplex also point to point & multi
    point to point communication.
    Not suitable for emergency services Suitable for emergency services due
    (Call set up time ~ a few seconds). to very fast call set up time (300 ms)

    Do not maintain privacy and mutual Maintain privacy and mutual security.
    security.
    Direct Mode Operation(DMO) is not Direct Mode Operation(DMO) is
    possible. possible, which supports voice and
    data transmission without a Base
    Station between Radio Terminals.
    123seminarsonly.com
    WORLD USAGE

    123seminarsonly.com
    Thank you
    123seminarsonly.com

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