Spectral Characteristics of Digital Modulations
Two factors that are important in evaluating the efficiency of any communication system are the bandwidth required to transmit the chosen signaling or modulation technique and the energy-per-bit-to-noise-spectral-density ratio. Whereas the latter factor is a well-defined quantity, the former can be defined in many ways [2–1]. Regardless of the definition, however, the required transmission bandwidth is directly related to the power spectral density (PSD) of the signaling scheme. Thus, efficient analytical methods for calculating this power spectral density are essential if one is to specify the spectral occupancy of the transmission channel.
KeywordsPower Spectral Density Signaling Scheme Elementary Signal Convolutional Code Digital Modulation
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