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A resonant microwave pulse compressor with a waveguide H-plane-tee-based energy extraction unit was studied in terms of its capability to produce output pulses that comprise a low-power long-duration (prepulse) and a high-power short-duration part. The application of such combined pulses with widely variable prepulse and high-power pulse power and energy ratios is of interest in the research area of electronic hardware vulnerability. The characteristics of output radiation pulses are controlled by the variation of the H-plane tee transition attenuation at the stage of microwave energy storage in the compressor cavity. Results of theoretical estimations of the parameters tuning range and experimental investigations of the prototype S-band compressor (1.5 MW, 12 ns output pulse; ∼13.2 dB gain) are presented. The achievable maximum in the prepulse power is found to be about half the power of the primary microwave source. It has been shown that the energy of the prepulse becomes comparable with that of the short-duration (nanosecond) pulse, while the power of the latter decreases insignificantly. The possible range of variation of the prepulse power and energy can be as wide as 40 dB. In the experiments, the prepulse level control within the range of ∼10 dB was demonstrated. [ABSTRACT FROM AUTHOR]

Abstract—An analysis is performed for the characteristics of an interference microwave switch with distributed switched wave power as a device for outputting energy from an active resonant microwave compressor. The proposed device is a cascade of conventional microwave switches based on H-tees connected in series with straight arms. It is shown that such a switch can multiply reduce the switched wave power by uniformly distributing it across the switches of the tees, which is done by adjusting the lengths of the tee arms. It was also established that between the lengths there is a functional relationship in which uniform distribution is achieved. The results of an experimental study of the microwave switch of two and/or three tees at low and high power are presented. [ABSTRACT FROM AUTHOR]

We present the results of studying a cascade microwave switch capable of stable operation at the power level of a regular waveguide. The cascade stage is formed by connecting several identical H-joints in the side branch of the tee of a conventional microwave interference switch. The connection distributes the power of the switched wave between the joints and varies the level of the switched power. The method of the scattering matrix is used to analyze the properties of such a switch based on H-joints with different matching levels of the side branch. It is shown that the cascade of sufficiently well-matched joints can decrease the level of the switched power by several times and ensure a higher operating power and a better stability of the switching, while the cascade with coupling worse than a certain boundary value can increase the power of the switched mode by several times and ensure switching of a lower-power mode. The numerical criterion of the coupling quality is found, which divides operation of the switch with increased and decreased switched powers. It is also found that in the switch under consideration, the microwave energy is distributed between the cascade elements in the process of the switching, which can affect greatly both the switching process and the characteristics of the switched mode during the process. The results of the analysis are compared with the experimental data at high and low power levels. [ABSTRACT FROM AUTHOR]

We propose a superconducting interference switch of a resonance microwave compressor on the basis of a waveguide H-plane tee, whose lateral arm contains a switching cavity having controllable parameters and based on another H-plane tee. The transmission coefficient of the switch is evaluated for the case of controlling the Q-factor and/or resonance frequency of the switching cavity externally. It is shown that the proposed switch can ensure high-efficiency transmission of the stored energy to the load at a minimal value of the controlling parameter (compared with the known solutions). [ABSTRACT FROM AUTHOR]

We propose a commutator for the interference switch of microwave electromagnetic radiation on the basis of a waveguide H-junction made as a cavity with tunable parameters, which is connected to one arm of this junction. The superconducting version of a microwave compressor with such a switch is analyzed. The conditions of effective switch operation in the mode of electromagnetic energy storage and its fast output in the case of controllable manipulation of the Q-factor and resonant frequency of the switching cavity are determined. Estimates of the output parameters of the superconducting compression system are presented for storing- and switching-cavity Q-factors of about 5 ・ 10. The possibility of increasing the radiated power in such a compression system by 40-60 dB for output microwave pulses with durations of about 5-10 ns is demonstrated. Variants of practical implementation of the system are considered. [ABSTRACT FROM AUTHOR]

Synchronous extraction of energy from cavity resonators for X-band microwave radiation through a compact packet of five interference switches based on H tees has been experimentally analyzed. It is shown that switches can be completely synchronized and the synchronization conditions are determined. Microwave pulses have been generated upon synchronous extraction of energy from five single-mode cavities (power ∼0.8 MW, gain ∼12 dB, and width ∼3.2 ns) and from one superdimensional cavity (power ∼2.2 MW, gain ∼16.5 dB, and width ∼3.5 ns). The operation limits of X- and S-band microwave compressors with extraction of energy through a packet are estimated. [ABSTRACT FROM AUTHOR]

Results of the experimental investigation of the resonant microwave pulse compression system operating in a 10-cm wavelength region are presented. The system contains two multimode resonators for storing high-frequency energy and a waveguide bridge for the fast and synchronous energy extraction. When powered from a magnetron generator having a radiation power of 5 MW and pulse duration of 4 μs, microwave pulses with an output power of ∼0.8 GW, duration of ∼5 ns, and pulse repetition rate up to 100 Hz were obtained in this compression system. [ABSTRACT FROM AUTHOR]

We present the results of theoretical analysis of the operation of a waveguide bridge as a device for microwave-energy extraction and the data of experimental studies of 3-cm compressors with energy extraction through the bridge. We determine conditions under which the bridge can be used as an efficient output device capable of doubling the output pulsed power of the compressor. [ABSTRACT FROM AUTHOR]

An experimental study of a resonance microwave (3-cm-range) compressor with gas insulation and energy output through a superdimensional coaxial interference switch is reported. The rated parameters of the compressor are output signal power ∼25 MW, signal duration 2 ns, gain 26 dB, and efficiency ∼57%. A gain of 20 dB was achieved at a peak output signal power of 12 MW, signal duration of 2 ns, efficiency of ∼24%, and traveling wave power of 24 MW. [ABSTRACT FROM AUTHOR]

A study is made of the production of high power nanosecond rf pulses by extracting microwave energy from an oversized cavity by means of conversion, at a coupling window, of the high-Q working mode to an auxiliary mode which is strongly coupled to an external load. It is shown that microwave rf pulse compressors with copper storage cavities and energy extraction by mode conversion at a coupling window can provide gains of 5–13 dB with output signal durations of 20–150 ns and peak powers of 5–10 MW in the 3-cm band and 50–100 MW in the 10-cm band. Rf pulses lasting 30 ns with peak powers of 0.5 MW have been obtained experimentally at a frequency of 9.4 GHz with a gain of 9 dB. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Results of an experimental study of the formation of rf pulses with controlled power, duration, repetition rate, and envelope parameters in a resonance compressor employing oscillation-mode transformation are presented. The pulse parameters are varied by using tuned intermodal coupling elements. A possibility of the formation of a series of subsecond and nanosecond rf pulses in the partial extraction of energy and nanosecond pulses of various durations in single complete extraction of energy from the compressor resonator is shown. [ABSTRACT FROM AUTHOR]

We have studied an interference switch based on an oversized H-plane rectangular waveguide T-junction. Conditions necessary for effective operation of the switch as an energy extractor are evaluated. Microwave pulses of 3.5-ns duration with 2.8-MW power at a gain of 17.5 dB have been obtained using a prototype microwave compressor for the 3-cm waveband with a 72 × 34 mm waveguide resonator and a 58 × 25 mm waveguide switch. It is shown that, using the proposed switch, it is possible to obtain RF pulses with a power of up to ∼0.1 GW in the 3-cm band and ∼1 GW in the 10-cm band. [ABSTRACT FROM AUTHOR]

The first results of an experimental investigation of the synchronization of two resonant microwave compressors by a laser beam are presented. It is shown that almost complete synchronization can be achieved and the corresponding conditions are determined. Using S-band compressors, a total output signal power of about 220 MW was obtained for 100% summed signals. The possibility of increasing the total output power up to 450 MW is justified. [ABSTRACT FROM AUTHOR]

Data on the summation of signals from two synchronously operating resonant microwave (3-cm) compressors with oversized cavities are described. The energy was extracted with interference switches. The summation was performed in a waveguide tee and a 3-dB three-slot bridge. For a signal duration of ∼30 ns at a level of 0.5, a peak power of ∼1 MW, and an efficiency of ∼30%, a gain was found to approach ∼11 dB. © 2000 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

The energy stored in a resonant cavity was extracted through four output ports and added in phase in a common line. Operation of a single switch provided synchronism and the power portions transmitted through the ports were combined in a waveguide turnstile junction. Estimation shows that the compressor peak power can reach a value eight times as much as the switched wave power, provided the output pulsewidth is shortened by the same factor with reference to the cavity double transit time. The performance of the X-band compressor prototype was investigated. Signals radiated through each of four output ports had identical envelope shapes and equal peak power values. The reflected wave did not accompany the power combining. The pulses of 1.2 MW peak power and 1.6 ns pulse width were obtained when the compressor was driven by the 50 kW pulse power magnetron generator. [ABSTRACT FROM AUTHOR]

A refinement is made to calculations of the microwave energy storage efficiency in a cavity. © 1999 American Institute of Physics. [ABSTRACT FROM AUTHOR]