A brief coverage of amplitude modulation (AM) and angle modulation techniques is provided. The basic principles of conventional AM, double-sideband suppressed carrier AM, single-sideband AM, and vestigial sideband AM are described both through time-domain and frequency-domain techniques. Frequency and phase modulation are described and their equivalence is argued. A comparison of different analog modulation techniques in terms of complexity, power, and bandwidth requirements is made. Conversion of analog signals into a digital form through sampling and quantization is studied. Proof of the sampling theorem is given. Scalar and vector quantizers are described. Uniform and non-uniform scalar quantizer designs are studied. The Lloyd-Max quantizer design algorithm is detailed. The amount of loss introduced by a quantizer is quantified by computing the mean square distortion, and the resulting signal-to-quantization noise ratio. Pulse code modulation (PCM) as a waveform coding technique, along with its variants – including differential PCM and delta modulation – is also studied.

The fundamentals of analog and digital modulation techniques are presented in Chapter 6. The theoretical underpinnings of the world's most popular amplitude modulations, frequency modulations, and phase modulations are presented. The impact of pulse shape and filtering on bit error rate of a mobile communication system is demonstrated, where Doppler spread creates an irreducible bit error rate no matter how good the signal-to-noise ratio, yet is below the noise created by other aspects of the radio system. This led Europe to select GMSK for the pan-European 2G digital cellular standard, whereas the US selected a pi/4 PSK modulation method originated in Japan that allows both coherent and non-coherent demodulation and a graceful upgrade path for existing operators to adopt the new digital modulation with gradual base station changeouts over time.Capacity and Shannon's limit are defined and explained through numerous examples.