FIGURE 1 - uploaded by D.M. Vavriv
Content may be subject to copyright.
Source publication
Experience in the development and application of transmitters for coherent radar systems based on millimeter-wave magnetrons is summarized. Design approaches to the development of highly efficient transmitters for frequencies of 36 GHz and 95 GHz with power level of 30 kW and 4 kW, respectively, are discussed. Meteorological Doppler radar systems b...
Context in source publication
Context 1
... block-diagram of the transmitter using a hard tube modulator is shown in Fig. 1. The transmitter includes the following main parts: a high-voltage power supply, which includes a power factor corrector, a filament power supply, a driver for the modulator tube, and a controller. The high power supply utilizes a flyback converter with current feedback. Such a scheme allows us to obtain a rather small voltage ripple ...
Similar publications
In multiple-input multiple-output radar systems, it is usually desirable to steer transmitted power in the region-of-interest. To do this, conventional methods optimize the waveform covariance matrix, R, for the desired beampattern, which is then used to generate actual transmitted waveforms. In this paper, we provide a low complexity closed-form s...
In multiple-input multiple-output radar systems, it is usually desirable to steer transmitted power in the region-of-interest. To do this, conventional methods optimize the waveform co- variance matrix, R, for the desired beampattern, which is then used to generate actual transmitted waveforms. In this pa- per, we provide a low complexity closed-fo...
Citations
The drift orbital resonance theory has the potential to analyze and estimate the electron dynamics in a magnetron. Hence it has been utilized to examine the behavior of the rotating electron cloud in a spatial harmonic magnetron (SHM). Alteration of the theory variables, namely the orbital velocities, coefficients of radial expansion, gyrating circle radius, accelerating factor, etc., affects the electron trajectory forming numerous epicycloid, hypocycloid, and circular patterns. These variables are dependent on some of the physical and electrical input parameters, namely the structural geometry, the applied voltage, the applied magnetic field, etc. They thus can be used to alter and predict the rotating electron’s trajectories, which in turn control the device performance as well as help to understand and visualize the response of the rotating electron cloud in the designed SHM. The manuscript also presents the analysis of the nature of the steady-state and transient response of the current components of the designed SHM (operating at 136 GHz) obtained from CST simulations and provide reasonable explanation using drift orbital resonance theory.
This article presents the effect of choosing a different operating region on the output performance of a spatial harmonic magnetron (SHM). A 28-vane SHM with a backward spatial harmonic of (
$\pi $
/2)−1 operating mode at 136 GHz has been modeled and analyzed for performance study using CST-particle studio. The steady-state output power of 4.83 kW at 11.10 kV applied voltage with an efficiency of 5.61% has been obtained. An increment in the output power is observed on the application of higher anode voltage, but the efficiency saturates as the applied voltage reaches 0.4 times the threshold voltage. A close observation of the electron cloud or spokes reveals a greater expansion of the electron cloud toward anode as compared to the conventional magnetron. This expansion of the space charge cloud closer to the anode surface results in better beam wave interaction. It is this expansion factor, which is the part of the threshold voltage that perturbs the electron spokes of the fundamental mode but has little effect on the overall steady-state electron cloud.
Radio frequency vacuum electronic devices (RF VEDs) have been quite a promising milestone in radiowave and microwave generation for decades. With advance technologies, the VEDs are now heading toward higher frequency range viz. millimeter (mm) wave and Terahertz (THz) with substantial power. The prompted techniques, improvisations, and improvements, particularly in magnetrons, have been substantial for propelling the modern day high frequency application requirements. The paper now puts a review in the context of the various techniques, structures, and technologies suggested and implemented to reassert the feasibility of magnetrons as a promising representative of VEDs for mm and THz radiation generation. Performance parameters like power, operating frequency, efficiency, etc., serve to examine the development trends of mm and THz magnetrons.
A millimeter-wave (mmw: 3 mm wavelength, W-band) radar permits short-range, high-resolution detection and imaging of the airport movement area. The main safety-related applications, which have been tested in Marco Polo (Venice) and Urbe (Roma) airports respectively, are the prevention of runway incursions and the management of Foreign Object Debris (FOD). Other potential applications, to be studied, are Bird-strike prevention and Intruder detection.
