amplituudiskreetmodulatsioon

Amplituudiskreetmodulatsioon, often abbreviated as ADM, is a digital modulation technique. It belongs to the family of amplitude modulation methods where the amplitude of the carrier signal is altered in discrete steps. Unlike analog amplitude modulation, which allows for a continuous range of amplitude values, ADM restricts the amplitude to a finite set of predefined levels.

The process of ADM involves quantizing the amplitude of the message signal before it is used to modulate the carrier. This quantization process discretizes the amplitude, resulting in the carrier signal taking on one of several specific amplitude values. The number of possible amplitude levels, often referred to as the order of the modulation, directly influences the data rate and noise immunity of the system. A higher number of levels allows for more bits to be encoded per symbol, increasing the data throughput, but also makes the system more susceptible to noise.

ADM is a form of digital communication, meaning the information being transmitted is in digital form. The discrete amplitude levels are used to represent binary or multi-level digital data. For example, in a simple binary ADM, the carrier might have two distinct amplitude levels, one representing a '0' and the other a '1'. More complex ADM schemes use more levels to encode multiple bits per symbol.

ADM systems can be susceptible to amplitude noise and interference, as these can distort the received amplitude levels and lead to errors. However, by employing error detection and correction codes, the reliability of ADM can be improved. ADM finds applications in various digital communication systems where a balance between simplicity, bandwidth efficiency, and robustness to certain types of channel impairments is desired.