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.
[1] [5] The phasor representation of sinusoidal voltages and currents is generalized to arbitrary waveforms. [2] This mathematical transformation eliminates the 60 Hertz (Hz) carrier which is the only time-varying element in the stationary case. [3] The longer usage of time-varying phasors in large power systems since 1920s have created many ...
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]
Bluetooth 1 modulates with Gaussian minimum-shift keying, a binary scheme, so either modulation choice in version 2 will yield a higher data rate. A similar technology, IEEE 802.15.4 (the wireless standard used by Zigbee ) also relies on PSK using two frequency bands: 868 MHz and 915 MHz with BPSK and at 2.4 GHz with OQPSK.
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 ...
A new version of the standard was released in December 2011, which split the IEEE C37.118-2005 standard into two parts: C37.118-1 dealing with the phasor estimation & C37.118-2 the communications protocol. It also introduced two classifications of PMU, M — measurement & P — protection.
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.
The user guide engraved into a model of the Antikythera Mechanism. User guides have been found with ancient devices. One example is the Antikythera Mechanism, [1] a 2,000 year old Greek analogue computer that was found off the coast of the Greek island Antikythera in the year 1900. On the cover of this device are passages of text which describe ...