RMS formula (root mean square) — definition, average power, and discrete signals
What RMS means for voltages and DSP signals, how it ties to average power, and the formulas for continuous and discrete waveforms.
Channel Modelling
Generate AWGN in Matlab/Octave without awgn() — variance from Eb/N0
Build AWGN from randn without Communications Toolbox: set noise variance from SNR or Eb/N0, generate real/complex noise, verify power.
Power delay profile (PDP) — multipath power vs delay
What a power delay profile is, how it shows multipath taps vs excess delay, and how it connects to delay spread and wireless channel models.
Multipath channel models: scattering function
Multipath & PDP (same on every page in this path) 1. Power delay profile → 2. Scattering function (you are here) → 3. TDL modeling Tools: PDP demo · 3GPP TDL Understand various characteristics of a wireless channel through multipath channel models. Discuss Wide Sense Stationary channel, uncorrelated scattering channel, wide sense stationary uncorrelated scattering … Read more
White noise in Matlab — generate AWGN, plot PSD, check variance
Simulate white / Gaussian noise in Matlab: generate with randn, verify variance and flat PSD, then reuse the noise model in BER simulations.
Symbol Timing Recovery for QPSK (digital modulations)
Digital Modulations Lab path:BPSK → QPSK → M-PSK simulation → QPSK symbol timing → π/2-BPSK (5G NR)Tools: BER vs Eb/N0 · EVM → SNR · OFDM CP overhead The goal of timing recovery is to estimate and correct the sampling instants and phase at the receiver, such that it allows the receiver to decode the … Read more
Log-distance path loss (log-normal shadowing) — model, PLE, and formula
Log-distance / log-normal shadowing path loss: formula beyond Friis, path-loss exponent by environment, shadowing χ, and how it extends free-space models.
Friis free-space path loss — formula, assumptions, and dB form
Friis transmission equation and free-space path loss: $latex (4\pi d/\lambda)^2$, dB form, assumptions, and when to move to log-distance or two-ray models.
Wireless channel models – an Introduction
The medium between the transmitting antenna and the receiving antenna is generally termed as “channel”. In wireless transmission, the characteristics of the signal changes as it travels from the transmitter to the receiver. The signal characteristics are due to several phenomena: 1) existence of line of sight path between the antennas, 2) reflection, refraction and … Read more
BPSK BER vs Eb/N0 — Rayleigh fading compared with AWGN (Matlab)
Why flat Rayleigh fading costs SNR versus AWGN for BPSK: BER vs Eb/N0 curves, formulas, and Matlab simulation comparison.