Objectives and outcomes
Students acquire basic knowledge of understanding the principles, analysis and design of digital
communication systems. Upon completion of the course, students understand the concept of the
frequency spectrum of signals, the principles of digitization of analogue signals, as well as digital
modulation techniques in the baseband and transposed range. Students are familiar with different types
of receivers – correlation receiver and receiver with the matched filter. They understand coherent and
non-coherent signal detection in AWGN channels and know how to calculate the mean bit error
probability. Students can quantify the amount of interference in the system and reduce it by equalization
methods. They are familiar with the concept of extended-spectrum signal transmission with direct
sequence and frequency hopping.
Lectures
Introduction to digital communications. Signals and spectra. Digitization of analogue signals. Sampling
and quantization. Digital transmission in the baseband. Pulse code modulation. Receiver with the
matched filter. Correlation receiver. Detection of digital signals in the presence of AWGN. Probability of
error. Symbol interference. Nyquist’s theorem. Impulse shaping and equalization. Signal space concept,
orthogonal signals. Digital modulations in the transposed range (ASK, PSK, FSK). Coherent and non-
coherent detection. Signal detection in channels with AWGN. Mean probability of error per symbol. Error
probability for different modulation technique. Spectrally efficient modulations. Broadband transmission.
Direct sequence. Frequency jumping. Multiple access techniques (TDMA, FDMA, CDMA).
Practical classes
Fourier transformation. Energy and power signals. Autocorrelation and convolution function. Digital
transmission in the baseband and the bandpass. Constellation diagrams and waveforms of signals in the
time domain for different digital modulations (PCM, ASK, PSK, FSK). Coherent and non-coherent
detection in AWGN channels. Mean probability of error per symbol/bit. Transmission without intersymbol
interference. “Raised cosine” filter. Intersymbol interference. Duobinary signalling. Spread-spectrum
transmission. DS-BPSK modulation. FH-MFSK modulation.