What distinguishes a digital receiver from an analog receiver?

A digital receiver is specifically designed to interpret signals that are represented in binary form—essentially as “on” (1) and “off” (0) levels. This is fundamentally different from an analog receiver, which processes signal variations continuously. The presence of decision circuitry in a digital receiver is what allows it to accurately determine whether a signal, which may be subject to noise and distortion, corresponds to "on" or "off" levels. This capability is crucial for maintaining data integrity, enabling digital receivers to recover the intended information even in less-than-ideal conditions.

In contrast, while advanced filtering techniques, inherent noise reduction, and operation at multiple frequencies may apply to both types of receivers, they do not distinctly set digital receivers apart from analog ones in the same fundamental way that decision circuitry does. Filtering and noise reduction can be used in various forms of reception, and there are analog receivers capable of operating at multiple frequencies as well. The essential characteristic that defines digital as distinct from analog is the method of signal interpretation, specifically through electronic means that determine discrete levels of signal status.