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The spectrum of a chirp pulse describes its characteristics in terms of its frequency components. This frequency-domain representation is an alternative to the more familiar time-domain waveform, and the two versions are mathematically related by the Fourier transform.
A chirp is a signal in which the frequency increases (up-chirp) or decreases (down-chirp) with time. In some sources, the term chirp is used interchangeably with sweep signal . [ 1 ] It is commonly applied to sonar , radar , and laser systems, and to other applications, such as in spread-spectrum communications (see chirp spread spectrum ).
In digital communications, chirp spread spectrum (CSS) is a spread spectrum technique that uses wideband linear frequency modulated chirp pulses to encode information. [1] A chirp is a sinusoidal signal whose frequency increases or decreases over time (often with a polynomial expression for the relationship between time and frequency).
and where f d is the Doppler frequency, B is the frequency sweep of the chirp, T is the duration of the chirp, f m is the mid (centre) frequency of the chirp, V r is the radial velocity of the target and c is the velocity of light (= 3×10 8 m/s). Consider as an example, a chirp centered on 10 GHz, with pulse duration of 10μs and a bandwidth ...
An ionosonde consists of: A high frequency (HF) radio transmitter, automatically tunable over a wide range. Typically the frequency coverage is 0.5–23 MHz or 1–40 MHz, though normally sweeps are confined to approximately 1.6–12 MHz.
The acoustic adaptation hypothesis predicts that narrow bandwidths, low frequencies, and long elements and inter-element intervals should be found in habitats with complex vegetation structures (which would absorb and muffle sounds), while high frequencies, broad bandwidth, high-frequency modulations (trills), and short elements and inter ...
Chirping, the act of signaling with chirps, signals in which the frequency increases / decreases with time Chirping, pulse compression by linear frequency modulation Trash-talk in ice hockey
The chirplet transform thus represents a rotated, sheared, or otherwise transformed tiling of the time–frequency plane. Although chirp signals have been known for many years in radar, pulse compression, and the like, the first published reference to the chirplet transform described specific signal representations based on families of ...