demodulation
Học thuậtThân thiện
Definition
Noun: 1. (Electronics) The process of extracting an original information signal from a modulated carrier wave. This is the fundamental operation in a receiver that reverses the modulation process, recovering the data (e.g., audio, video, digital data) that was imposed on the carrier wave for transmission.
Usage
- General Use: The term is used almost exclusively in the fields of electronics, telecommunications, and signal processing to describe a specific technical function within a receiver circuit.
- Context: It is commonly discussed alongside its counterpart, modulation. A complete communication system requires modulation at the transmitter and demodulation at the receiver.
Examples
- Noun:
- The radio receiver performs demodulation to convert the received radio frequency signal back into audible sound.
- A key component in any modem is the demodulation circuit, which recovers the digital data from the analog telephone line signal.
- The quality of the demodulation process directly affects the clarity of the received signal.
Advanced Usage
- Coherent Demodulation: A sophisticated demodulation technique that requires the receiver to have precise knowledge of the carrier wave's phase and frequency for optimal signal extraction.
- Envelope Demodulation: A simpler, non-coherent method often used in AM radio receivers, which extracts the signal by following the envelope (outer shape) of the modulated wave.
Variants and Related Words
- Demodulate (verb): To perform the act of demodulation.
- The circuit is designed to demodulate the incoming signal efficiently.
- Demodulator (noun): The specific device or circuit that performs demodulation.
- The demodulator is a critical component in the satellite receiver.
- Modulation (noun): The complementary process of impressing an information signal onto a carrier wave for transmission.
Synonyms
- Detection: A historical and sometimes interchangeable term in radio communications, particularly for amplitude modulation (AM).
- Signal Extraction: A descriptive phrase for the general concept.
Related Phrases/Concepts
- Modem: A portmanteau of Modulator and Demodulator, a device that performs both functions for digital data communication.
- Tuning and Demodulation: In a radio, tuning selects the desired carrier frequency, and demodulation then extracts the audio signal from it.
Noun
- (electronics) the reception of a signal by extracting it from the carrier wave