Q - What is DTH ?

    DTH Means Direct to Home or you can say it is Direct to Home Television.

    DTH is the system through which one can view television Programmes. It is  called Direct to Home because we
    receive the TV Programmes direct from the Broadcaster. There will be no one in-between Broadcaster and
    Subscriber except satellite.

    In  the DTH , Broadcaster receives TV Channels from different Programming source  like Star plus,  Zee tv  etc.
    Broadcaster process these received signals and  transmit to the satellite.

    Subscriber  receives  TV signals direct from satellite by fixing one small  Dish antenna on the terrace or balcony in
    the particular direction.  By connecting one STB ( Set top Box ) to the Dish antenna and to the Television one can
    enjoy TV programmes with various interactive features. (TOP)

 

   Q - What is working principal of DTH ?

    Working principal of DTH is the satellite communication. Broadcaster modulates the received signal and transmit it
    to the satellite in KU Band and from satellite one can receive signal by dish and set top box. (TOP)

    Q - What is KU Band ?

    KU Band is the band of frequency ranging from 8 to 18 GHz. This is very high band of frequency which is used for
    DTH to transmit the signals. (TOP)

    Q - Why DTH uses KU Band ?

    DTH uses KU Band to transmit the signals from broadcasting (UPLINK) centre to the satellite which is 36000 Km
    away from the earth equator. As we know that KU Band is the very high frequency band and it can travel this
    much distance with less deterioration. High frequency can travel long distance and Low frequency can travel less
    distance as per theory. (TOP)

    Q - What is uplink centre ?

    UPLINK Centre is also called broadcasting centre. It is the centre located on ground to process the signals received
    from different programming source and transmit it to the satellite. (TOP)


                                          

    Q - What is satellite ?

    A body which revolve or rotate around a planet is called satellite. There are basically two types of satellite.....

    1.Natural satellite. Moon is the natural satellite because moon revolves a planet (earth).
    2.Artificial  or  man  made satellite.  This satellite is the wireless  body which revolve the planet and used for the
       communication purpose. This satellite is launched into the space by rocket and placed in orbit around the earth.
        (TOP)

    Q - How DTH satellite works ?

    DTH  satellites are launched into the space by rocket and it is placed on the Geostationary orbit. It is the orbit
    which  is approx 36000 km  away from equator of the Earth. This satellite  is placed in such a way that it can
    transmit signals to the required geographical area. This satellites revolve around the earth in such a way that it
    always point to the required geographical area of the earth. (TOP)

    Q - What is transponder in the satellite ?

    Transponders are like electronic blocks in the satellite who receives and transmit the signal. Transponder receives
    signals from UPLINK centre and after processing those signals it transmit back to the mini dishes installed on the
    ground. DTH service providers can transmit the number of channels depending upon the number of transponders
    allotted to them. Less No. of transponder means less No. of channel transmission.

    If any broadcaster wants to transmit more No. of channels over a less No. of Transponder then he has to compress
    the digital data of the channels. In this case the quality of reception may reduce and it will create pixilation of
    channel. (TOP)

    Q - How to align a mini dish antenna on ground ?

    To receive signals from the satellite you have to fix one mini dish on the ground in such a way that the front of the
    dish must face to the satellite without any obstruction in between. To align a dish with particular satellite you must
    know the latitude and longitude of the area where you have to install a dish. Other than latitude and longitude you
    also should know the orbital position of the satellite you want to track.

    There are mainly two alignments require to track the satellite with mini dish. 1) Azimuth angle alignment 2) Elevation
    angle alignment.  (TOP)

    Q - What is Azimuth angle ?

    Azimuth angle is the horizontal alignment of the mini dish. You can set this angle by using magnetic compass.
    You should know the azimuth angle of your area or it can be calculate by knowing latitude, longitude and orbital
    position of the satellite. (TOP)

    Q - What is Elevation angle ?

    Elevation angle is the vertical alignment of the mini dish. You can set this angle by using angle finder or inclino
    meter.You should know the azimuth angle of your area or it can be calculate by knowing latitude, longitude and
    orbital position of the satellite. (TOP)

    Q - What is LNB ?

    LNB means Low Noise Block down converter. It is the electronic component which is fitted on the mini dish. It
    receives the reflected signals from mini dish, down coverts into the low frequency (GHz to MHz) and feeds the
    signals to the set top box. (TOP)

    Q - What is the effect of rain water on DTH transmission ?

    As we have discussed DTH uses KU Band for signal transmission. KU Band can be absorb by the water. If there is
    heavy rain fall then DTH transmission may be disturb and you will not get the signals properly. The freezing of
    picture may occur during heavy rain fall.

    But if you or your engineer has aligned dish to the peak level then there are less chances of disturbance. (TOP)