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  2. Chirplet transform - Wikipedia

    en.wikipedia.org/wiki/Chirplet_transform

    More precisely, a chirplet is a windowed portion of a chirp function, where the window provides some time localization property. In terms of time–frequency space, chirplets exist as rotated, sheared, or other structures that move from the traditional parallelism with the time and frequency axes that are typical for waves (Fourier and short ...

  3. IEEE 802.15.4a - Wikipedia

    en.wikipedia.org/wiki/IEEE_802.15.4a

    The IEEE 802.15 Low Rate Alternative PHY Task Group (TG4a) for wireless personal area networks (WPANs), as its name implies, was tasked with amending the 802.15 standard to provide alternate PHY standards that would allow for high aggregate throughput (much throughput over time) communications with a precision ranging capability (within 1 meter accuracy) and low power usage within the scope of ...

  4. Chirp - Wikipedia

    en.wikipedia.org/wiki/Chirp

    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 ).

  5. Chirped pulse amplification - Wikipedia

    en.wikipedia.org/wiki/Chirped_pulse_amplification

    One or multiple reflections between a pair of chirped mirrors or similar device allow any form of chirp. This is often used in conjunction with the other techniques to correct for higher orders. The Dazzler is a commercial pulse shaper in which light is diffracted from an acoustic wave. By tuning the timing, frequency, and amplitude of the ...

  6. Chirp compression - Wikipedia

    en.wikipedia.org/wiki/Chirp_compression

    The chirp pulse compression process transforms a long duration frequency-coded pulse into a narrow pulse of greatly increased amplitude. It is a technique used in radar and sonar systems because it is a method whereby a narrow pulse with high peak power can be derived from a long duration pulse with low peak power.

  7. Chirp spread spectrum - Wikipedia

    en.wikipedia.org/wiki/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).

  8. Chirp spectrum - Wikipedia

    en.wikipedia.org/wiki/Chirp_spectrum

    They have a phase angle close to a value of π /4 within the chirp range / and they only start to change significantly for frequencies beyond this range. Consequently, for frequencies within the sweep range of the chirp, it is the square-law phase term Φ 1( ω ) and its group delay function ( = -d Φ 1/d( ω ) ) that are of most interest.

  9. Pulse compression - Wikipedia

    en.wikipedia.org/wiki/Pulse_compression

    The advantages [4] of the Barker codes are their simplicity (as indicated above, a de-phasing is a simple sign change), but the pulse compression ratio is lower than in the chirp case and the compression is very sensitive to frequency changes due to the Doppler effect if that change is larger than .