Spectral Analysis

Discussion of spectral analysis

Fourier Synthesis and Generating Pulses

Pulse Spectrum

Bat Signal - Bat Spectrogram

Some Voice Characteristics

Human Signal - Human Spectrogram-1 and Human Spectrogram-2

Formants (Wikipedia definition)

Formants

Formats from the Handbook of Acoustical Ecology

The Singing Formants

Vowel Space

Revisiting the nature of sound signals

See IVSR Wave Basics - Ways of Showing Waves

Discussion of sound signals using sndwave

Channel Encoding: Modulation

All About Modulation (local pdf) part of the valuable Complex2Real.com tutorial series

Frequency Channel Encoding: Amplitude Modulation

Frequency Channel Encoding: Angle Modulation

Frequency Channel Encoding: Pulse Modulation

From the excellent series of interactive applet tutorials available from Hewlett-Packard:

Generating Waveforms with Vectors (Phasors)

Generating Pulses

3D View Generating Pulses

Amplitude Modulation

Time Domain vs. Frequency Domain

 Multiple Access Methods (Multiplexing)

Frequency Multiplexing - Frequency Division Multiple Access (FDMA)
 

Bell's Harmonic Telegraph (Reference)

FDMA Channel Allocations

Multiplex Paradigm-1: This figure shows a schematic of multiple voice channels aggregated into a channel or message group by using frequency multiplexing.

Multiplex Paradigm-1: This figure shows multiple channel groups aggregated into a higher-order supergroup, again, by using frequency multiplexing.

Temporal Multiplexing - Time Division Multiple Access (TDMA)

TDM configuration

TDMA Channel Allocations