Bandwidth of linear modulated signals, I Brief detour on modeling using random processes Transmitted symbols modeled as random, so transmitted signal is a random process Power spectral density (PSD) and autocorrelation functions can be defined as empirical averages over a single sample path –Corresponds to a particular stream of transmitted symbols Bandwidth can be defined as fractional power containment bandwidth (exactly as we did for energy containment bandwidth), or as 3 dB bandwidth, etc.
{"Image DocumentName": "Two-dimensional modulation, contd.", "Image ImageDescription": "Assume that the transmit pulse is real-valued (for simplicity of discussion). I and Q components of complex baseband transmitted signal are given by. In rectangular QAM, we choose Re(b[n]) and Im(b[n]) independently from the same. real-valued constellation. For example, from {-1,+1} for 4-QAM, and {-3,-1,+1,+3} for 16-QAM. Amplitude and phase of complex baseband transmitted signal over nth symbol. governed by |b[n]| and arg(b[n]). PSK corresponds to keeping |b[n]| constant. and choosing arg(b[n]) from a finite set of possibilities. There are many possible two-dimensional. constellations that cannot be classified as. either rectangular QAM or PSK.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}