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The carrier-envelope phase (CEP) or carrier-envelope offset (CEO) phase is an important feature of an ultrashort laser pulse and gains significance with decreasing pulse duration, in a regime where the pulse consists of a few wavelengths. Physical effects depending on the carrier-envelope phase fall into the category of highly nonlinear optics.
A second form of precise monitoring is called carrier-phase enhancement (CPGPS). [1] The error, which this corrects, arises because the pulse transition of the PRN is not instantaneous, and thus the correlation (satellite–receiver sequence matching) operation is imperfect. The CPGPS approach utilizes the L1 carrier wave, which has a period of
Real-time kinematic positioning (RTK) is the application of surveying to correct for common errors in current satellite navigation (GNSS) systems. [1] It uses measurements of the phase of the signal's carrier wave in addition to the information content of the signal and relies on a single reference station or interpolated virtual station to ...
The AN/SPY-1 [a] is a United States Navy passive electronically scanned array (PESA) 3D radar system manufactured by Lockheed Martin, and is a key component of the Aegis Combat System. The system is computer controlled and uses four complementary antennas to provide 360-degree coverage.
Prior to the addition of the phase-modulated time code, WWVB identified itself by advancing the phase of its carrier wave by 45° at ten minutes past the hour, and returning to normal (a −45° shift) five minutes later. This phase step was equivalent to "cutting and pasting" 1 ⁄ 8 of a 60 kHz carrier cycle, or approximately 2.08 μs.
The two amplitude-modulated sinusoids are known as the in-phase (I) and quadrature (Q) components, which describes their relationships with the amplitude- and phase-modulated carrier. [ A ] [ 2 ] Or in other words, it is possible to create an arbitrarily phase-shifted sine wave, by mixing together two sine waves that are 90° out of phase in ...
Each symbol is encoded as a different phase shift of the carrier sine wave: 0°, 45°, 90°, 135°, 180°, 225°, 270°, 315°. A constellation diagram is a representation of a signal modulated by a digital modulation scheme such as quadrature amplitude modulation or phase-shift keying. [1]
If the phase-offset/delay of the multiply-filter-divide system is known, it can be compensated for to recover the correct phase. In practice, applying this phase compensation is complicated. [4] In general, the modulation's order matches the nonlinear operator required to produce a clean carrier harmonic. As an example, consider a BPSK signal.