If you are a Headend Engineer or working for cable industry like Headend INFO then there is basic need for you to understand the phenomenon behind the C Band Ku Band system. These two things are most essential part of a headend weather it is Digital Headend or Analog Headend.
Satellite Communication
There are lot of satellites are available in the orbit which are responsible for the communication like TV Network , Satellite Phone , Military Services , Weather information and GPS (Global Positioning System).
Transmitter , Antenna , Power Generator and Amplifier are the equipments which we are using in the satellite communication. The Orbit is divided into two sections like
GSO
LEO
GSO
GSO stands for Geo Stationary Orbit. It is 35,786 Km above the earth equator and its rotation is synchronized with the earth’s equator. There are lot of satellites placed in the Geo stationary orbit because these are wider in size and cover lot of space with the high transmission power.
LEO
LEO stands for Lower Earth Orbit. LEO is 3000 Km above the earth equator. LEO satellites transmission power is not high as the the satellites are in the GSO also the satellites are not wider as compared to GSO.
Classification Of Bands
BANDS | RANGE |
L-Band | 1 – 2 GHz |
S-Band | 2 – 4 GHz |
C-Band | 4 – 8 GHz |
X-Band | 8 – 12 GHz |
Ku-Band | 12 – 18 GHz |
K-Band | 18 – 27 GHz |
Ka-Band | 27 – 40 GHz |
V-Band | 40 – 75 GHz |
W-Band | 75 – 110 GHz |
L Band (1-2 Ghz)
L band space is very expensive because there is not much bandwidth available in the L band. Lower Earth Orbit Satellite uses the L Band. L Band beam is wider and RF equipment for this is not expensive. L Band equipments are easy to use because there is not need of accuracy of beam because of its wider beam.
Applications of L band
Miltary Satellites , GPS (ground positioning system) Satellites , Satellite Phones and WorldSpace satellite Radio.
C Band (4-8 GHz)
C Band satellite transmit approximately 6 Ghz and receive approximately 4 Ghz. We use large antenna for C band that is around 2.4 to 3.7 meter in size. At some particular location in the world the requirement of the C Band antenna size is 3 to 3.7 meter for proper reception of signals. The larger antenna size gives less interference.
Downlink frequency range for C Band is 3.7 to 4.2 Ghz while Uplink frequency range for C Band is 5.9 to 6.4 Ghz.
Ku Band (12-18 Ghz)
This is called the lower portion of the K Band because this letter connected “u” with K comes from the German word which means under.
As we know this is higher frequency range for this we need high accuracy of beam. Because beam is narrow for the Ku band. We use the small size dish for the reception of signal as compared to the C band. The size for the Ku band is around 1 meter of dish.
This is generally using for satellite TV and VSAT. There is one major problem with Ku Band is that signals are droped in rainy weather. But this problem can be avoided by using high transmission power which cost you more. Also this problem can be avoided by using large diameter dish.
Ka Band (18-40 GHz)
The letter “a” connected with K comes from German word which means above. So this is called the above K-band.
This is extremely high frequency band and also it is expected that it will be using for future also. It is less expensive band. We need high accuracy for the Ka band due to its narrow beam for which we need to purchase high quality RF equipments which are expensive.
Ka Band is using for High Definition Satellite TV , Satellite Phone backhaul and also for Terrestrial VSAT.
This was all about the C Band Ku Band System.
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