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FIGURE 6. Hyalessa maculaticollis. Echemes structure. A, Power frequency spectrum represented with overlay of 52 spectra computed from echemes with high amplitude oscillations showing a dominant frequency marked by F3. B, Detailed oscillogram showing the first echeme with low amplitude oscillations and the second echeme with high amplitude oscillations. C, Power frequency spectrum represented with overlay of 71 spectra computed from echemes with low amplitude oscillations showing dominant frequencies marked by F1 and F2.
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FIGURE 8. Hyalessa fuscata. Echemes structure. A, Power frequency spectrum represented with overlay of 47 spectra computed from echemes with high amplitude oscillations showing dominant frequencies marked by F1, F2, F3 and F4. B, Detailed oscillogram showing the first echeme with low amplitude oscillations and the second echeme with high amplitude oscillations. C, Power frequency spectrum represented with overlay of 38 spectra computed from echemes with low amplitude oscillations showing dominant frequencies marked by F1 and F2.
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Oscillation modes
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The station here is setup to receive two frequencies simultaneously. SpectrumLab is setup to do simultaneous FFT calculations and tabulate Doppler Shift and signal amplitude data for each frequency. The radio used is a K3 in the CW mode with AGC off. The main and subrx of the K3 are identical and phase locked. The antenna is a multiband Vee antenna facing north averaging 15' high. FFT parameters are adjusted for a bin width of 0.186 Hz with the SL peak detection algorithm turned on to determine the peak frequency within the bin. 75% overlap. A data point is obtained every 1.3 seconds. Doppler shift is determined via the heterodyne method differencing the station pitch and the reference oscillator (offset in freq). Both oscillators are locked to a Rubidium standard. The attached plots are the station setup, Doppler shifts for CHU 14670 kHz and 15000 kHz, and the amplitudes of each.
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In this paper, electromagnetic analysis of the reltron, which is a compact, simple and efficient high power microwave (HPM) source has been presented. The beam wave interaction process of the reltron oscillator has been analyzed to understand the device physics. The split cavity oscillator and relativistic klystron principles have been extended to demonstrate the electric field responsible for beam bunching and the electron beam modulation process in the reltron. The analytical formulation to obtain the RF energy growth and efficiency of the device has also been presented. To validate the analytical results and to evaluate the overall performance of the device, beam present simulation of reltron has been performed using commercial 3D PIC simulation code "CST Particle Studio".  With the parameters of a  previously reported experimental reltron device, the present analytical calculation provided ~240 MW RF output power with ~38% efficiency while the PIC simulation provided RF output power of ~225 MW with ~36% efficiency at 2.75 GHz frequency. The obtained analytical and simulation results have also been found in agreement of ~6% with this experimental work.
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Operating frequency 2.75 GHz
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In this paper, electromagnetic analysis of the reltron, which is a compact, simple and efficient high power microwave (HPM) source has been presented. The beam wave interaction process of the reltron oscillator has been analyzed to understand the device physics. The split cavity oscillator and relativistic klystron principles have been extended to demonstrate the electric field responsible for beam bunching and the electron beam modulation process in the reltron. The analytical formulation to obtain the RF energy growth and efficiency of the device has also been presented. To validate the analytical results and to evaluate the overall performance of the device, beam present simulation of reltron has been performed using commercial 3D PIC simulation code "CST Particle Studio".  With the parameters of a  previously reported experimental reltron device, the present analytical calculation provided ~240 MW RF output power with ~38% efficiency while the PIC simulation provided RF output power of ~225 MW with ~36% efficiency at 2.75 GHz frequency. The obtained analytical and simulation results have also been found in agreement of ~6% with this experimental work.
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In other words, the symmetric tree representation does not su±ce to obtain a good ¯t between the model and the measured impedance data. Another observation is that the constant-phase behavior is emphasized at frequencies below those evaluated standardly in clinical practice, i.e. below 5Hz. However, in the standard clinical range of frequencies for the forced oscil- lation technique, namely 4-48Hz, both symmetric and asymmetric tree models give similar results, as depicted in ¯gure 4 and ¯gure 5.
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Another observation is that the constant-phase behavior is emphasized at frequencies below those evaluated standardly in clinical practice, i.e. below 5Hz. However, in the standard clinical range of frequencies for the forced oscil- lation technique, namely 4-48Hz, both symmetric and asymmetric tree models give similar results, as depicted in ¯gure 4 and ¯gure 5.
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FIGURE 42. Multiplicity relationship between "instantaneous" dominant frequency and w of calls A of eight Physalaemus species. Each graph shows a single call A of P. orophilus (A), P. lateristriga (B), P. olfersii (C), P. riograndensis (D), P. biligonigerus (E), P. marmoratus (F), P. santafecinus (G), P. carrizorum (H). Grid corresponds to the harmonic values (right y-axis). Red squares are the values of "instantaneous" dominant frequency; blue circles are the values of the reciprocal of w; green triangles are the factor values of the ratio "instantaneous" dominant frequency / w reciprocal per delta time. Delta time corresponds to the duration of one period of the measured acoustic oscillation. Note that factors around integer values suggest harmonic relationship between the frequency calculated (w reciprocal) and the dominant frequency. Factors multiple of ½ of the fundamental frequency correspond to subharmonics (see call B of P. ephippifer).
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