Mobile radio propagation channels are characterized by three primary statistical parameters derived from power delay profiles: time dispersion metrics (mean excess delay, RMS delay spread), frequency selectivity measures defined by coherence bandwidth ($B_c \approx 1/(5\sigma_\tau)$ or $1/(\alpha\sigma_\tau)$), and temporal variation described by Doppler spread and coherence time. These parameters quantify the channel's multipath dispersion in both time and frequency domains, establishing mathematical boundaries between flat-fading versus frequency-selective regimes and slow-fading versus fast-fading conditions based on correlation thresholds (e.g., 0.5 or 0.9). The theory enables system designers to predict intersymbol interference limits, determine the necessity for equalization techniques, and architect diversity schemes that exploit independent fading in orthogonal time-frequency slots to mitigate signal degradation.
Mobile radio propagation channels are characterized by three primary statistical parameters derived from power delay profiles: time dispersion metrics (mean excess delay, RMS delay spread), frequency…