Frequency modulated continuous wave (FMCW) radar works on the principle of continuously varying the frequency of the transmitted signal over time. In FMCW radar, a continuous signal is transmitted with a frequency that builds up or down linearly over a defined period. This continuous variation in frequency results in a continuous waveform that serves as both the transmitted signal and the local oscillator for mixing with the received signal.
By comparing the transmitted and received signals, the FMCW radar can determine the range to a target based on the frequency difference (beat frequency) between the two signals. This principle allows FMCW radar to achieve high resolution in range measurements and is commonly used in applications such as automotive radar, altimeters and range finders.
Frequency modulation (FM) is a form of modulation where the frequency of a carrier wave is varied in accordance with the amplitude of a modulating signal.
The key principle of FM modulation is to encode information on the carrier wave by varying its frequency. In FM modulation, the frequency of the carrier wave increases or decreases in proportion to the amplitude of the input signal (modulation signal). This modulation technique is widely used in broadcasting and communication systems as it provides better noise immunity compared to amplitude modulation (AM).
FM modulation allows efficient transmission of audio signals and data over long distances without significant quality degradation.
Amplitude modulation (AM) is a modulation technique where the amplitude of a carrier wave is varied in accordance with the amplitude of a modulating signal. The fundamental principle of AM modulation involves the superposition of information (audio signal or data) on the carrier wave by varying its amplitude. In AM modulation, the amplitude of the carrier wave is varied in proportion to the instantaneous amplitude of the modulating signal.
This modulated signal is then transmitted through the medium, such as Air for Radio Broadcasting. AM modulation is simpler to implement compared to FM and is historically significant in radio communication, although it is more susceptible to noise and interference than FM modulation
