Signal Processing for Communication Systems
In coherent detection, the receiver derives its demodulation frequency and phase references using a carrier synchronization loop. Such synchronization circuits may introduce phase ambiguity $latex \phi = \hat{\theta}-\theta $ in the detected phase, which could lead to erroneous decisions in the demodulated bits. For example, Costas loop exhibits phase ambiguity of integral multiples of $latex … Read more
Analytic Signal Lab (same on every page in this path) 1. Hilbert / FFT → 2. Envelope & IF → 3. Phase demodulation (you are here) Tools: Hilbert / analytic signal demo Key focus: Demodulation of phase modulated signal by extracting instantaneous phase can be done using Hilbert transform. Hands-on demo in Python & Matlab. … Read more
Extract amplitude envelope, instantaneous phase, and instantaneous frequency via the analytic signal — practical Hilbert/FFT notes.
How the analytic signal and Hilbert transform give envelope and instantaneous phase/frequency, FFT implementation tips, and links to the envelope follow-on.
FIR vs IIR tradeoffs: linear phase, stability, order, and when each wins — with links to digital filter design articles.
Multipath & PDP (same on every page in this path) 1. Power delay profile → 2. Scattering function → 3. TDL modeling (you are here) Tools: PDP demo · 3GPP TDL A brief intro to modeling a frequency selective fading channel using tapped delay line (TDL) filters. Rayleigh & Rician frequency-selective fading channel models explained. … Read more
OFDM study path — 5 lessons (same on every page in this series) 1. Introduction → 2. Orthogonality → 3. IFFT modem → 4. Cyclic prefix (you are here) → 5. BER in AWGN Tools: OFDM CP overhead calculator · Eb/N0 ↔ SNR converter In one sentence: A cyclic prefix tricks a natural (linear) … Read more
How to get amplitude and phase from an FFT: |X[k]|, atan2, why phase looks noisy, the magnitude threshold fix, Matlab + Python, and links to bins/fftshift and the FFT calculator.
How DFT bins map to Hz, what negative frequencies mean, when to use fftshift/ifftshift, and how this pairs with magnitude/phase plots.
What RMS means for voltages and DSP signals, how it ties to average power, and the formulas for continuous and discrete waveforms.