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In the homodyne or synchrodyne system, a local oscillator was tuned to the desired input frequency and multiplied with the input signal.
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homodyne and system
The homodyne tomography system functions as an amplifier.
homodyne and local
In optical interferometry, homodyne signifies that the reference radiation ( i. e. the local oscillator ) is derived from the same source as the signal before the modulating process.
In heterodyne detection, the local oscillator is frequency-shifted, while in homodyne detection it has the same frequency as the radiation to be detected.
homodyne and frequency
* In homodyne detection, the interference occurs between two beams at the same wavelength ( or carrier frequency ).
homodyne and with
In that case, the homodyne mixer translates the signal frequencies by ( A + B )/ 2, with a synchronized phase, which moves the highest component to ( B − A )/ 2 and the Nyquist rate to just ( B − A ).
This technique combines the advantages of the high efficiencies of photodiodes in measuring the intensity or photon number of light, together with measuring the quantum features of light by a clever set-up called the homodyne tomography detector.
homodyne and signal
In optical Kerr effect ( OKE ) spectroscopy, optical heterodyning of the OKE signal and a small part of the probe signal produces a mixed signal consisting of probe, heterodyne OKE-probe and homodyne OKE signal.
The probe and homodyne OKE signals can be filtered out, leaving the heterodyne signal for detection.
One of the photons is used as a trigger signal used to trigger ( start ) the readout event of the homodyne tomography detector.
More simply said, it is only when the trigger photon is measured, that the signal photon can be measured by the homodyne detector.
homodyne and .
Figure 1: The electric field, measured by optical homodyne detection, as a function of phase for three coherent states emitted by a Nd: YAG laser.
One notable example is in the tomography of light, known as optical homodyne tomography.
Using balanced homodyne measurements, one can derive the Wigner function and a density matrix for the state of the light.
Balanced homodyne tomography is a reliable technique of reconstructing quantum states in the optical domain.
The other photon is directed into the homodyne tomography detector, in order to reconstruct its quantum state.
Now let us consider the homodyne tomography detector as depicted in figure 4.
Common detection techniques include: interferometry ( homodyne or heterodyne or Fabry – Pérot ) and optical beam deflection ( GCLAD ) or knife edge detection.
system and local
As a source of investment capital, the system is beneficial to local communities and encourages the development of industries in rural areas.
This condition will undoubtedly continue until such time as a state uniform system of evaluation is established, or through mutual agreement of the local assessing officials for a method of standard assessment practice to be adopted.
This weakness is not unique to labor surplus areas, for it is inherent in the system of local school districts in this country.
For a time following the abandonment of the local plant, electric current for Manchester was brought in from the south with an emergency tie-in with the Vermont Marble Company system to the north.
The local community maintains responsibility for the financial support of its own library program, facilities, and services, but wider resources and additional services become available through membership in a system.
* 1871 – Emperor Meiji orders the Abolition of the han system and the establishment of prefectures as local centers of administration.
* Automated Systems Holdings Limited, Largest local system integrator in Hong Kong
Some ANACs are very regional or local in scope, while others are state -/ province-or area-code-wide: there appears to be no consistent national system for them.
After the release of the Apple Lisa computer in January 1983, Apple invested considerable effort in the development of a local area networking ( LAN ) system for the machines.
The bulk of the documents relate to the running of a large, private estate is named after Heroninos because he was phrontistes ( Koine Greek: manager ) of the estate which had a complex and standarised system of accounting which was followed by all its local farm managers.
In Belgium an extensive system of tram-like local railways called vicinal or buurtspoor lines crossed the country in the first half of the 20th century, and had a greater route length than the main-line railway system.
The system was originally built as a patchwork of local rail links operated by small private railway companies.
Under his command, a modern update of the doctrinal system called Bewegungskrieg (" maneuver warfare ") and its associated leadership system called Auftragstaktik (" mission tactics "; i. e., units are assigned missions ; local commanders decide how to achieve those missions ) was developed, which was a critical advantage and a major reason for the success of blitzkrieg.
Among many achievements, Henry institutionalized common law by creating a unified system of law " common " to the country through incorporating and elevating local custom to the national, ending local control and peculiarities, eliminating arbitrary remedies and reinstating a jury system – citizens sworn on oath to investigate reliable criminal accusations and civil claims.
Once judges began to regard each other's decisions to be binding precedent, the pre-Norman system of local customs and law varying in each locality was replaced by a system that was ( at least in theory, though not always in practice ) common throughout the whole country, hence the name " common law.
Essentially, every country that was colonised at some time by England, Great Britain, or the United Kingdom uses common law except those that were formerly colonised by other nations, such as Quebec ( which follows the law of France in part ), South Africa and Sri Lanka ( which follow Roman Dutch law ), where the prior civil law system was retained to respect the civil rights of the local colonists.
Some communities have developed their own " Local Exchange Trading Systems " ( LETS ) and local currencies, such as the Ithaca Hours system, to encourage economic growth and an enhanced sense of community.
As neighboring territories of these warring states, including areas of modern Sichuan and Liaoning, were annexed, they were governed under the new local administrative system of commandery and prefecture ( 郡縣 / 郡县 ).
In addition, border security Chekas were included in the system of local Cheka bodies.
system and oscillator
For a single degree of freedom oscillator, a system in which the motion can be described by a single coordinate, the natural frequency depends on two system properties: mass and stiffness ; ( providing the system is undamped ).
In classical mechanics, a harmonic oscillator is a system that, when displaced from its equilibrium position, experiences a restoring force, F, proportional to the displacement, x:
If F is the only force acting on the system, the system is called a simple harmonic oscillator, and it undergoes simple harmonic motion: sinusoidal oscillations about the equilibrium point, with a constant amplitude and a constant frequency ( which does not depend on the amplitude ).
The quantum harmonic oscillator is an exactly-solvable system where the different representations are easily compared.
An undamped Harmonic oscillator # Spring – mass system | spring – mass system is an oscillatory system.
Systems where the restoring force on a body is directly proportional to its displacement, such as the dynamics of the spring-mass system, are described mathematically by the simple harmonic oscillator and the regular periodic motion is known as simple harmonic motion.
* In dynamical system theory an oscillator is called isochronous if the frequency is independent of its amplitude.
A master frequency generator or master electronic oscillator, in frequency-division multiplexing ( FDM ), is a piece of equipment used to provide system end-to-end carrier frequency synchronization and frequency accuracy of tones.
Generally speaking, radio frequency engineers speak of the phase noise of an oscillator, whereas digital system engineers work with the jitter of a clock.
The exact response of a resonance, especially for frequencies far from the resonant frequency, depends on the details of the physical system, and is usually not exactly symmetric about the resonant frequency, as illustrated for the simple harmonic oscillator above.
For a lightly damped linear oscillator with a resonance frequency Ω, the intensity of oscillations I when the system is driven with a driving frequency ω is typically approximated by a formula that is symmetric about the resonance frequency:
A physical system can have as many resonant frequencies as it has degrees of freedom ; each degree of freedom can vibrate as a harmonic oscillator.
Namely, one considers the phase space of the corresponding classical system ( e. g. for an ensemble of quantum harmonic oscillators, the phase space of a classical harmonic oscillator is considered ).
Note also that if there are conditions where β A < sub > OL </ sub > = − 1, the amplifier has infinite amplification – it has become an oscillator, and the system is unstable.
In this case, a sketch of the phase portrait may give qualitative information about the dynamics of the system, such as the limit cycle of the Van der Pol oscillator shown in the diagram.
That is, a dynamical system within the oscillator continuously dissipates its internal energy.
Any oscillator whose oscillations are driven by a system that almost always is dissipating energy may be called a relaxation oscillator.
The ultraviolet catastrophe results from the equipartition theorem of classical statistical mechanics which states that all harmonic oscillator modes ( degrees of freedom ) of a system at equilibrium have an average energy of.
0.320 seconds.