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   channel coding · spread spectrum · OFDM · LEO

MATLAB Domain Topics Validation


A hands-on simulation library covering the full digital communications stack — from binary channel coding and error correction to spread-spectrum CDMA systems and live LEO satellite link budgets. Every result is derived analytically and validated by Monte Carlo simulation.


What's Inside

🔐 Module 1 — Channel Coding & Error Detection

Files: A1/EX1.m, A1/EX2.m, A1/EX3.m

Linear block codes characterised by generator matrix G and parity-check matrix H — built from scratch. Derived the full distance spectrum, computed undetected-error probability analytically, then cross-validated against BSC Monte Carlo runs across six decade-spaced BEP values.

Key concepts implemented:

  • Systematic (8,4) linear block codes — two competing code designs compared head-to-head
  • Hamming weight distributions and minimum distance extraction
  • CRC generator polynomial design and detection-capability evaluation
  • Syndrome-based error detection over a Binary Symmetric Channel

⚡ Module 2 — Hard vs. Soft Decoding & Synchronisation

Files: A2/EX1.m, A2/EX2.m, A2/EX3.m

Side-by-side analytical and simulated comparison of hard-decision vs. soft-decision decoding. Derived the union bound and asymptotic bound on codeword error rate for soft decoding and demonstrated the 2–3 dB gain over hard decoding empirically.

Key concepts implemented:

  • Maximum Likelihood hard decoding with syndrome lookup table
  • Soft-decision decoding: union bound and asymptotic approximation vs. simulation
  • Linear Feedback Shift Register (LFSR) design — maximal-length m-sequences generation
  • Synchronisation marker insertion and detection
  • Autocorrelation and power spectral density via FFT

🌐 Module 3 — Spread Spectrum, CDMA & OFDM

Files: A3/EX1.m, A3/EX2.m, A3/EX3.m

From sequence design theory to a full CDMA system simulation and adaptive OFDM bit allocation.

Key concepts implemented:

  • Gold sequence generation (degree-7 polynomials, N=127 chips) — autocorrelation and cross-correlation characterised and plotted
  • Welch and Sidelnikov bounds on sequence sets, evaluated across family sizes
  • CDMA multi-user system: interference analysis and capacity limits
  • OFDM adaptive bit loading via the Hughes-Hartogs algorithm — per-subcarrier SNR-aware allocation to maximise throughput over a frequency-selective channel

🛰️ Module 4 — LEO Satellite Link Budget

File: A4/A4.m

End-to-end satellite communication system modelled in MATLAB's Satellite Communications Toolbox. Simulated a sun-synchronous LEO orbit (500 km, 97.4° inclination) over a 7-day scenario with a 60-second propagation timestep.

Key concepts implemented:

  • Orbital mechanics: satellite scenario creation with Keplerian parameters
  • Four global ground stations (Inuvik, Svalbard, Awarua, Troll)
  • Gaussian dish antenna sizing (0.18 m satellite, 3.7 m ground) with aperture efficiency
  • Link budget: EIRP, G/T, free-space path loss, Doppler, Eb/N₀ margin
  • Access interval and visibility window analysis across the station network
  • Channel degradation: ITU-R P.618 rain attenuation model

Tech Stack

Tool Role
MATLAB Core simulation & visualisation engine
Communications Toolbox BSC, AWGN channels, Gold sequence generator
Satellite Communications Toolbox Orbital mechanics, link budget, ground station modelling
Signal Processing Toolbox FFT-based correlation, PSD analysis

Skills Demonstrated

Channel Coding · Error Correction · Monte Carlo Simulation · Spread Spectrum · CDMA · OFDM · LFSR / m-sequences · Gold Sequences · Satellite Link Budget · Orbital Mechanics · Analytical-Simulation Cross-Validation


M.Sc. Communications Engineering — Politecnico di Torino

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MATLAB simulations covering channel coding, CDMA, OFDM adaptive bit loading, and LEO satellite link budgets. Analytical derivations validated by Monte Carlo.

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