C band and ku band.

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Greatkarthik

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Now a days many discussions going on ddf regarding c band and ku band channels. I am new to this. Pls help me reg this. What is it ?
 
The C band is a name given to certain portions of the electromagnetic spectrum, including wavelengths of microwaves that are used for long-distance radio telecommunications. The IEEE C-band - and its slight variations - contains frequency ranges that are used for many satellite communications transmissions, some Wi-Fi devices, some cordless telephones, and some weather radar systems. For satellite communications, the microwave frequencies of the C-band perform better under adverse weather conditions in comparison with Ku band (11.2 GHz to 14.5 GHz) microwave frequencies, which are used by another large set of communication satellites.

The Ku band (English pronunciation: /ˌkeɪˈjuː/) is a portion of the electromagnetic spectrum in the microwave range of frequencies. This symbol refers to (originally German: Kurz-unten)—in other words, the band directly below the K-band. In radar applications, it ranges from 12-18 GHz according to the formal definition of radar frequency band nomenclature in IEEE Standard 521-2002.
Ku band is primarily used for satellite communications, most notably for fixed and broadcast services, and for specific applications such as NASA's Tracking Data Relay Satellite used for both space shuttle and ISS communications. Ku band satellites are also used for backhauls and particularly for satellite from remote locations back to a television network's studio for editing and broadcasting. The band is split into multiple segments that vary by geographical region by the International Telecommunication Union (ITU). NBC was the first television network to uplink a majority of its affiliate feeds via Ku band in 1983.
 
1. What is the difference between Ku Band Satellite Dishes, Free To Air Satellite Dish, & Offset Satellite Dish Antennas, and C band satellite dishes?
Ku band satellite dishes usually range anywhere between 18 inches (40cm) to 1.2m (48 inch). Most Free To Air FTA dishes are Ku band. C band satellite dishes can also be used for FTA. C band dishes are are larger in size. Usually 1.8 meters | 6 feet and larger. C band dishes are usually prime focus. With a Ku band LNB specially designed for a C band dish, you can use a C band dish to pick up a Ku band signal.

2. What is the difference between a prime focal dish and an offset satellite dish?

The difference between the offset satellite dish and prime focal (prime focus) dish is the way the signal reflects from the surface and where it gets concentrated.
Prime Focus Dishes, the signal reflects from the satellite dish and concentrates towards the center, where the LNB is mounted to catch the signal.

Offset Dishes are designed with an offset angle. Usually set at 21-degrees. With this design, the signal reflects from the dish and concentrates towards the bottom of the satellite dish instead of the center of the satellite dish. See the pictures below:

Prime focus C band dish :

prime-focus-c-band-dish.jpg


Offset Ku band dish :

offset-ku-band-dish.jpg
 
Thanks @Ashwani for ur compliments :)

This is an important difference and should be known to all satellite and dish enthusiasts.. :)
 
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