An aspect of receiver design that affects the system design is the IF filter bandwidth in the satellite receiver. Ideally the filter should be matched to the bandwidth of the signal being transmitted.
If it is too wide the received signal will suffer an unnecessarily reduced carrier-to-noise ratio and will have noisier looking pictures than necessary. If the filter is too narrow the system will have a higher carrier-to-noise ratio but will filter out some of the wanted signal. This appears as horizontal extensions on white or yellow edges of images. It is particularly noticeable on captions. This effect is known as truncation noise.
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