Terminology — what do we call processing an analog signal in the digital domain? Choose the correct term for the manipulation, analysis, and transformation of signals after converting them to numeric form and operating on them with algorithms.

Introduction / Context:
Once an analog signal is sampled and quantized by an ADC, subsequent operations—filtering, detection, compression, spectral analysis—are performed numerically. The umbrella term for these algorithmic operations executed by processors, DSP cores, or FPGAs is Digital Signal Processing (DSP). Distinguishing DSP from conversion steps is foundational for system architecture.

Given Data / Assumptions:

• Analog signals are first acquired via sensors and ADCs.
• Digital hardware or software performs computations on sampled data.
• Outputs may remain digital or be reconverted to analog via DACs.

Concept / Approach:
DSP includes time- and frequency-domain operations such as FIR/IIR filtering, FFT-based spectral estimation, adaptive filtering, and modulation/demodulation in software-defined radios. The key is that the manipulation happens numerically, not by analog components. ADC and DAC are conversion interfaces, not the manipulation itself, while “signal filtering” without context could be analog or digital.

Step-by-Step Solution:

Verification / Alternative check:
Standard textbooks define DSP as the analysis and manipulation of signals using digital techniques, distinct from the conversion steps themselves.

Why Other Options Are Wrong:

• Analog-to-digital conversion: the front-end conversion, not the manipulation.
• Digital-to-analog conversion: output interface, not processing.
• Signal filtering: ambiguous; could be analog filtering as well.
• Amplitude modulation: a specific analog/digital communications technique, not the general term.

Common Pitfalls:

• Equating “digital filter” with ADC; the filter is the processing after conversion.

Final Answer:
Digital signal processing