Mode amplitude-modulation

The laser interferometer consists of two coupled resonators, one containing the laser, the other the plasma under investigation (Fig. 10). The laser radiation, reflected back from mirror A/s, which contains phase information about the refractive index of the plasma, interferes with the laser wave in cavity A, resulting in an amplitude modulation of the laser output 267). This modulation can be related to the refractive index and therefore to the plasma frequency and electron density. With a curved rather than a planar mirror, the sensitivity can be increased by utilizing transverse cavity modes 268). 

The quality of the profile pertaining to the selected region can be improved by a modulation of the pulse lengths within the pulse train, which mimics the amplitude modulation of a simple soft pulse [8]. Simple modulation schemes can be devised for attenuating or even suppressing the side-lobes in the vicinity of the selected region (as shown in fig. 3). Alternatively, more elaborated modulation schemes as those of the BURP family [9] can be run in the DANTE-Z mode [10]. This mode actually offers a... 

For linear systems, the principle of superposition applies, and different oscillatory modes can evolve independently of one another. However, biological systems in general are not linear, and separation of different regulatory mechanisms may not be justified, even when they involve different time scales. One type of phenomenon that can arise from the interaction between two oscillatory modes is modulation of the amplitude and frequency of the faster mode in dependence of the phase of the slower mode. This type of phenomenon was demonstrated in Fig. 12.2c where the frequency of the myogenic mode fjast changes in step with the amplitude of the TGF-mediated mode. Similar modulation phenomena can be expected to occur in many other biological systems such as, for instance, the interaction between the circadian and the ultradian rhythms of hormone secretion [25]. 

The mode-locked pulse train is one of a range of ways of comparing optical frequencies. A second technique which we have been investigating is the use of a frequency modulated (FM) dye laser. This has similarities to the mode-locked laser in that we are using the precise nature of the mode spacing when intracavity modulation is applied. In the case of the FM laser phase modulation is applied and in the case of the mode-locked laser amplitude modulation is applied. 

It is quite obvious from the above that disorder of any kind will reduce the CDW or BOW responses and the PLD fluctuations. Consequently, T% will decrease and will eventually disappear for large enough disorder [69]. Defects will also pin the Frolich mode and produce phase and amplitude modulations in the order parameter. Impurities may ionize (dopants) and produce charged solitons and discommensurations [70]. The commensurability pinning will decrease, affecting the soliton energy and width, as does the umklapp pinning. 

From equation (8) three modes of adiabatic spin inversion using RF pulses may be defined as (a) amplitude modulated pulses, e.g. I-BURP [13], G3[16], I-SNOB [17], (b) frequency modulated pulses, e.g. chirp [18,20], tangential sweep [20,21] and (c) both amplitude and frequency modulated pulses, e.g. the hyperbolic secant [22] or WURST (Wide band Uniform Rate Smooth Truncation) [23] pulse. 

The simple textbook solution of a harmonic damped oscillator becomes complex when the vibrating tip interacts with the surface of a sample, e.g., in tapping mode AFM. Although the different imaging modes and the experimental observables may vary, the underlying physics is similar. Amplitude and frequency modulated AFMs are most commonly used, labeled by AM-AFM (amplitude modulation or tapping) and FM-AFM. For a detailed review of this topic several reviews are available, e.g., [15]. 

Amplitude modulation Frequency modulation Phase imaging mode Error mode... 

A data set from an experiment to which TPPI has been applied is simply amplitude modulated in tx and so can be processed according to the method described for cosine modulated data so as to obtain absorption mode lineshapes. As the spectrum is symmetrical about Fx = 0 it is usual to use a modified Fourier transform routine which saves effort and space by only calculating the positive frequency part of the spectrum. 

In the following discussion the experimental procedures to extract frequency discriminated spectra with pure absorptive lines from amplitude modulated data is outlined. The analogous procedure for phase modulated data is discussed in the paragraph on the Echo/Antiecho detection mode. As shown in equation [2-15] taking the... 

Modulators are needed to convert electrical signals into optical amplitudes or phase modulations. Polymeric waveguides may be more compatible with integrated optics owing to processing considerations, and will be much cheaper to manufacture. Routing switches, electrooptic shutters, and amplitude modulators are imponant components for optical communications networks. Directional couplers, mode sorters, and Mach-Zender interferometers (Figure 2) are representative of the specific device mechanisms. These devices can op-... 

As a consequence of the voltage-controlled destructive interference, the applied electrical signal is transduced onto the optical beam as an amplitude modulation. The birefringent modulator depicted in Eig. 3.11b functions as an electri-cal-to-optical signal transducer. Here, both TM and TE optical modes traverse... 

From the velocity difference of the modes (u, k ) and (Uy, k ) follows the linear birefringence of the medium. By placing the shear transducer in the xy-plane with polarization 45° to the x-, y-axes, the different velocities seen in fig. 24 give rise to an amplitude-modulated signal because of the resulting phase change. 

Waveforms Operation of a mini-CIT requires five waveforms drive rf (2.000 MHz) and rf amplitude modulation potentials, ion isolation waveform, and ac potentials for ion excitation and for mass-selective axial ejection. Typical ac amplitude used in the mini-CIT for CID is 2Vo p and is applied in dipolar mode to the end-cap electrodes. The frequency used for resonant ejection is an octapole resonance that causes rapid ejection of ions. In Figure 8 is shown a typical timing diagram of scan function by which an El mass spectrum may be obtained. A scan function is a diagram showing the temporal relationships of the various potentials applied during... 

Amplitude, modulation mode or dynamic force mode... 

Figure 5. Schematical representation of the amplitude modulation mode. Parts of the image were...

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