SWEPT CARRIER
CEBus is a swept-carrier system, vulnerable to any noise in the 100 to 400 kHz range. CEBus is not a true Spread Spectrum system, because it does not process incoming signal according to Spread Spectrum theory and consequently does not show the processing gain normally associated with real Spread Spectrum systems. For example, a true Spread Spectrum system (100-400 kHz carrier, 10 kHz modulation rate) would offer about -15 dB Signal to Noise ratio, i.e., noise 5 times the signal. CEBus is specified at 3 dB, i.e., noise only 0.7 times that of the signal. For noise under 100 kHz or over 400 kHz, a CEBus system typically uses a simple second-order band-pass filter, that leads to poor protection against noise outside its main band.
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