Digital Communications

The course aims to deepen the knowledge of students in physical layer technology topics of current communication networks systems which students have been taught in the context of the courses Computer Networks I , II . The objective of this course is to highlight the building blocks of modern digital communications systems analyzing the function and performance corresponding to different types of channels (copper, fiber, wireless environment , etc. ).

Upon successful completion of this course the student / her will be able to:

• Understand the basic concepts that define the performance of a digital communication system (Entropy, noise, bandwidth, error rate, spectral efficiency, channel capacity).
• Understand the operation of the structural configuration steps, source coding and channel.
• Distinguish the main characteristics of amplitude modulation techniques, phase, frequency and their variants (ASK, PSK, FSK, PAM, QAM).
• Use basic tools for simulation of operating digital communications systems.
• Analyze and calculate the performance of digital communications systems relating the channel quality, the spectral efficiency and the need to correct or detect errors.
• Use basic laboratory equipment (oscilloscope, spectrum analyzer, communications analyzer, arbitrary signal generator, error rate analyzer, etc.) in order to ascertain the performance of digital transmission systems.

• Introduction in telecommunication systems
• Fourier transform, spectral analysis of simple waveforms, filters
• Analog modulation (AM, FM, PM)
• Sampling and quantization (PAM, PCM, DM)
• Source entropy and source coding – Huffman, Shannon Fano codes
• Digital modulation (ASK, PSK, FSK, QPSK, QAM)
• Noise, Signal to noise ratio, understanding of dB and its use in communications, Bit error rate and its relation to signal to noise ratio.
• Line coding, Error correction and detection (Block codes, Reed Solomon, BCH)
• Overview of the technical aspects of modern communication systems (ADSL, Wireless communications, Ethernet, Optical Communications

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2. B. Andy, Ψηφιακές Επικοινωνίες, Εκδόσεις Τζιόλα, Εκδόσεις Τζιόλα, (2000).
3. B. Sklar, Ν. Μήτρου, Ψηφιακές επικοινωνίες, εκδόσεις παπασωτηρίου, (2011)