Classification of communication systems. Channel impairments: attenuation, distortion, noise, etc. Continuous-wave (CW) modulation. Double Sideband Suppressed Carrier (DSB-SC), Amplitude Modulation (AM) and Quadrature Amplitude Modulation (QAM). Bandwidth. Mixers. Coherent detection and effects of frequency/phase errors. Frequency Modulation (FM) and Phase Modulation (PM). AM and FM transmitters, receivers and radio broadcasting. Noise sources and noise representation in CW modulation. Signal-to-Noise Ratio (SNR) calculations. Frequency Division Multiplexing (FDM) and Time Division Multiplexing (TDM). Introduction to baseband transmission: sampling, quantization, line coding, and pulse shaping. Introduction to digital modulation techniques: ASK, FSK, PSK and QPSK. Introduction to performance of digital modulation schemes in the presence of noise.