Phase tuning approach for polyharmonic power amplifiers

In this paper, new conditions for achieving the high efficiency and high output power capability of polyharmonic power amplifies are presented. These conditions can be used in future development of new types of polyharmonic amplifiers with similar efficiency and output power capability as those of Class F amplifies. However, a quite difficult tuning of an output network as in class-F amplifiers is not required

Class-E microwave oscillator

The class-E oscillator with the directed coupler in the feedback is studied. The similar design allows to retune the oscillator with preservation of high efficiency due to a constancy of a directed coupler coupling coefficient in band of readjustable frequencies and absence of the additional selective resonator in the feedback. Influence of spurious elements of the transistor on generation conditions in class-E is considered. The experimental breadboard of a class-E oscillator with output power 500 mW and efficiency 65% on frequency 800 MHz is investigated

Periodic structures on coupled slot resonators in the grounding layer of microstrip transmission line

The spectrum of natural frequencies of the resonator has been calculated. The specified resonator includes a microstrip transmission line with discontinuity in the form of two rectangular coupled slot resonators in the grounding layer. Based on the above spectrum and using the transverse resonance method the scattering matrix of the principal wave of the microstip transmission line on this discontinuity was calculated. The scattering characteristic of the periodic structure consisting of a finite number of cells in the form of coupled slot resonators in the grounding layer of microstrip line indicates that with due regard for their mutual coupling the losses in the first stopband can be reduced by 3–5 dB as compared with the characteristic obtained by tandem connection of the scattering matrices of separate slot resonators in the grounding layer of microstrip line

Analysis of a waveguide-slot transmission line with a metal-dielectric insert in the slot

The paper gives in strict formulation the solution to the problem of proper waves in a waveguide-slot transmission line (WSL) with a rectangular metal-dielectric inclusion in the slot imitating the behavior of a cutoff diode in this line. An algorithm is deduced for calculation of the generalized matrix of wave scattering by a usual WSL on the WSL segment with a “diode”. Based on the calculated data about the reflection loss, a matching network for a microwave attenuator in two pin-diodes, composed of two WSL segments, is built and optimized

Analysis of H-shaped slot resonators in microstrip line ground plane for stopband filter design

The scattering characteristic of microstrip line main mode on discontinuity in the form of H-shaped slot resonator in its ground plane is calculated by transverse resonance technique (TRT). The mutual coupling effect between slot resonators on distances between them, comparable with length of the distributed discontinuity is investigated

Scattering at a four-port vertical microstrip–slotline transition

The rigorous analysis of three types of characteristic oscillations has been conducted in a stripline-slot resonator formed by the mutually-perpendicular strip and slot transmission lines (three-layer structure). Scattering matrix for a four-port vertical microstrip–slotline transition has been built on the basis of the resultant solution of boundary problems for the stripline–slot resonator

A microstrip version of class-E microwave amplifier

The paper is devoted to design and experimental investigation of a microwave class-E amplifier built in MESFET, type CLY5, and intended for operation at frequency 820 MHz. The simulation results show a good agreement with the experiment

Analysis of coupled slot resonators of complex shape in metalization plane of a micro-strip transmission line using the transversal resonance techniques

The transverse resonance techniques is developed for analyzing three-layer planar structures based on micro-strip transmission line with slot resonators of complex shape in the grounding plane. Development of the techniques consists in considering higher space harmonics of current density in the strip line and mutual coupling between the slots in the grounding plane when numerically solving the boundary problem. In order to verify the techniques we conduct analysis of structures that consist of two coupled U- and symmetrical H-shaped slot resonators in the grounding plane of the micro-strip transmission line

Class E microwave amplifier built on a SiC transistor with high on-state resistance

Theoretical and experimental investigations of a wide-band microstrip-design class E amplifier on a SiC MESFET have been performed with due regard for the transistor on-state resistance. The efficiency versus passband relationships obtained by experiments are in good agreement with the results of theoretical calculation