Search results
Results from the WOW.Com Content Network
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.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
In telecommunications, a carrier wave, carrier signal, or just carrier, is a periodic waveform (usually sinusoidal) that initially carries no information. Through a process called modulation , one or more of the wave's properties are modified by an information bearing signal (called the message signal or modulation signal ) to convey information.
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 ...
The peak amplitude and the frequency of the carrier signal are maintained constant, but as the amplitude of the message signal changes, the phase of the carrier changes correspondingly. Phase modulation is an integral part of many digital transmission coding schemes that underlie a wide range of technologies like Wi-Fi , GSM and satellite ...
If the information to be transmitted (i.e., the baseband signal) is () and the sinusoidal carrier is () = (), where f c is the carrier's base frequency, and A c is the carrier's amplitude, the modulator combines the carrier with the baseband data signal to get the transmitted signal: [4] [citation needed]
The analytic representation is a generalization of the phasor concept: [2] while the phasor is restricted to time-invariant amplitude, phase, and frequency, the analytic signal allows for time-variable parameters.
Phase-shift keying (PSK) is a digital modulation process which conveys data by changing (modulating) the phase of a constant frequency carrier wave.The modulation is accomplished by varying the sine and cosine inputs at a precise time.