informationsignals

Information signals are signals that convey information rather than serving merely as a carrier or a background artifact such as noise. In communications and signal processing, the information signal is the part of the transmitted or detected signal that carries the intended data or message. It can be a function of time that is continuous (analog information signals) or discrete (digital information signals), and it may be represented before and after modulation or sampling.

Analog information signals include speech, music, and other real-world measurements, while digital information signals consist of encoded bit streams that represent data. Information signals can be transmitted in baseband or modulated onto a carrier, depending on the channel and system design. Their practical treatment often involves assumptions about bandwidth, power, and statistical properties.

From a theoretical perspective, information signals are modeled as stochastic or deterministic processes. Their bandwidth and average power influence how much information can be conveyed through a channel. In information theory, information content is described by entropy, and the achievable information rate is bounded by channel capacity, which depends on the signal, noise, and channel conditions.

Processing of information signals typically includes sampling, quantization, coding, and modulation to prepare for transmission, followed by demodulation and decoding at the receiver to recover the original information signal with acceptable fidelity. Applications span telecommunications, wireless networks, streaming media, sensor networks, and biomedical signal processing.