Modelling of digital communication systems
Description
In the Digital Communication System Modelling course you will learn to build models of digital communication systems with usage of the Engee visual modelling environment. Using the library blocks Communication Systems you will learn to build models of communication channels with additive white Gaussian noise, fading and power loss in free space, build signal constellation plots, perform digital signal modulation and demodulation (including OFDM modulation), calculate bit error rate (BER), filtering, as well as set phase and frequency distortion of digital signals.
Each section contains a theoretical part and assignments for independent fulfilment.
Knowledge requirements: Completion of Welcome to Engee and Visual modelling
Total course time: ~3 hours.
Course Programme
Modelling a simple digital communication line
Examines the general structure of a digital communication system, provides a brief introduction to digital modulation and in particular QPSK modulation and the Gaussian communication channel. The model of a QPSK modulated signal travelling through a Gaussian communication channel is studied. The bit error rate (BER) is calculated.
Digital modulation and demodulation
Signal constellation construction and BER calculation for signals with different types of digital modulation (QPSK, BPSK, PSK, QAM and M-APSK) are studied.
Filtering of digital signals
Brief information about low-pass filters and the filter with impulse response of the "raised cosine" type is given. A model of a filtered QAM-modulated signal passing through a Gaussian communication channel with BER calculation is studied.
OFDM modulation
Brief information about OFDM modulation is given and a model of a digital communication system based on OFDM modulation is built.
Distortions of digital signals
Fading channels, free-space signal power loss, phase and frequency distortion are studied. Models are built to demonstrate these types of signal distortions.