Microwave analog signal processing

Microwave Real-time Analog Signal Processing (R-ASP), as an alternative to DSP-based processing, might be defined as the manipulation of signals in their pristine analog form and in real time to realize specific operations enabling microwave or millimeter-wave and terahertz applications. The surging demand for higher spectral efficiency in radio has spurred a renewed interest in analog real-time components and systems beyond conventional purely digital signal processing techniques.

Source: Wikipedia — Microwave analog signal processing (CC BY-SA 4.0)