Signal Systems

		Signal Systems
			There are two signal systems 1. C-Band System transmits in the frequency spectrum of 3.4 – 4.2 Ghz. The frequency band is wide and covers many countries. Advantage: this system is suitable for a big country because the range of the transmitted frequency could be covered nationwide by only one satellite. For example in America, Russia, China and Indonesia. Disadvantage: because of the big coverage area the satellite needs 4-10 footprints.   2. KU-Band System transmits with 10-12 Ghz which is higher than C-Band. Its coverage area is smaller, that's why it's mostly used within single country coverage, such as in America, Japan and in Europe. Advantage: the signal strength is high, that's why the small satellite dishes (80-120 centimeter) can be used. For example, the CabelTV receives the signal through DBS (DIRECT BROADCAST SATELLITE) with 11.7 – 12.5 Ghz in the Digital Compression from America. Disadvantage: the footprint of KU-Band is narrow, and the coverage range is small. The signal loss is higher than in C-Band, so the pictures can disappear in bad weather