3.25.2008

Requirements for input signals in multiswitch systems

In the case of large multiswitch installation there have to be used many amplification stages, which increases the noise figure of such system. It directly translates into increase of BER. BER values above 10-4 (in the outlet) will prevent the user from receiving satellite broadcasts (the receiver will not be able to restore the original signal). To ensure reliable and high quality decoding, the BER values should be at least about 10-8 (in LNB outputs). Signals with low BER are ensured by use of appropriate dishes, e.g. 110 cm. It is very wise to use large dishes - the whole multiswich system needs only one set of dishes, being a small part of the total costs, but deciding on the quality of the input (and output) signals.

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