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QAM modulation simulation — rectangular constellations in Matlab and Python

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Digital Modulations 101 — 5 lessons (same on every page in this path) 1. BPSK → 2. QPSK → 3. M-PSK sim → 4. QAM sim (you are here) → 5. EVM Tools: BER vs Eb/N0 · EVM → SNR · Eb/N0 ↔ SNR Also on the Matlab → Python path (lesson 3 of 4): … Read more

M-PSK simulation — Matlab and Python BER curves for higher-order phase shift keying

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Digital Modulations 101 — 5 lessons (same on every page in this path) 1. BPSK → 2. QPSK → 3. M-PSK sim (you are here) → 4. QAM sim → 5. EVM Tools: BER vs Eb/N0 · EVM → SNR · Eb/N0 ↔ SNR Also on the Matlab → Python path (lesson 4 of 4): … Read more

Derive BPSK BER – optimum receiver in AWGN channel

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BPSK Lab path:Derive BER (theory) → AWGN noise model → BER simulation (Python & Matlab)Tools: BER vs Eb/N0 calculator · Shannon capacity Key focus: Derive BPSK BER (bit error rate) for optimum receiver in AWGN channel. Explained intuitively step by step. BPSK modulation is the simplest of all the M-PSK techniques. An insight into the … Read more

Derivation of expression for a Gaussian Filter with 3 dB bandwidth

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In GMSK modulation (used in GSM and DECT standard), a GMSK signal is generated by shaping the information bits in NRZ format through a Gaussian Filter. The filtered pulses are then frequency modulated to yield the GMSK signal. GMSK modulation is quite insensitive to non-linearities of power amplifier and is robust to fading effects. But … Read more

Bandpass sampling (undersampling) — allowed fs zones, Matlab/Python demo

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Bandpass / IF undersampling: choose sampling rates inside allowed zones so the replica does not alias — with formulas and a live bandpass sampling demo.