An improved analytical method for triple stub matching (Stubs in Parallel)

In this paper we give the new improved analytical method of triple stub tuner for matching the load impedances to provide the maximum power transfer between a generator and a load. The stubs are connected in parallel with the line at the appropriate distances from the load. The characteristic impedances of the transmission line and the stabs are different. The paper points on the determination of the length for the first stub near the load. The limit lengths for the first and the second stub are found for which the matching is possible. The length of the third stub is directly obtained from the matching conditions. Even though there is not the unique solution for the triple stub matching we also shoved the existence of unique solutions under some conditions. The special cases are also treated. The results of this method are verified by those obtained using the Smith chart and there are in exceptionally good agreement. Even though there are not many papers on this subject this work could be useful for engineers, and physicist which work in this domain.

Selecting a Compressor Meridional Topology: Axial, Mixed, Radial

This paper proposes a new duty-based Smith Chart as part of an improved method of selecting the geometric topology of compressors (axial, mixed or radial) in the earliest stage of design. The method has a number of advantages over previous methods: it is based on the non-dimensional flow and the non-dimensional work, which aligns with the aerodynamic function of the compressor and is therefore more intuitive than specific speed and specific diameter. It is based on a large number of consistently designed compressor rotors which have been computationally predicted using RANS CFD. Most importantly, it provides the designer not only with a choice of topology but also with the complete meridional geometry of the compressor, its blade design and the number of blades. This fidelity of geometry at the very early stage of design allows the designer to undertake a true systems design optimization (noise, manufacturing, packaging constraints and cost). This has the major advantage of significantly reducing early stage design times and costs and allows the designer to explore completely new products more quickly.

Bandwidth Analysis of a Broadband Amplifier with Two-Stage Matching System Using the Smith Chart

This paper describes a novel trace structure for the analysis and design of two-stage Broadband Frequency Low Noise Amplifiers based on standard Smith chart procedures and program algorithm realization. The method allows to put the transistor's S-parameters and details of the source and load networks and to interactively explore the effects of these quantities on design variables such as gain, noise figure and stability. It also facilitates the design of two-element matching networks to transform the source and load impedances to optimum values to achieve the desired gain and noise performance. The extended Smith chart concept is proposed to enable the advanced graphical interpretation of devices containing complex properties. This methodology is based on the Smith chart concept, and makes it easy to deal with devices containing signal sources, nonlinearity, very high Q factors and negative resistances. The concept of explaining the use of the Smith chart in combination with using modern tools as MATLAB scripts is exemplified in graphical forms. Phyton-based program contains the algorithm for parameters calculation. It explains the procedure that must be used to solve the two-stage impedance-matching problem. The point of this proposal is using of Smith chart plane for the graphical processing for its application to oscillator analysis. To demonstrate the effective usage of this methodology an interpretation and analysis of the oscillator, especially in terms of gain, noise and stability, are provided. The practical relevance concludes results of multistage design using impedance matching LC networks for the intersection level. The values of the parameters of the integrated microcircuit confirm the possibility of using the calculation methodology considered in the paper. The proposed solution is validated with extensive RF measurements at 3.5 GHz and is benchmarked against several frequency ranges for noise, stability and gain values. The methodology shown in the paper can be used in the development and design of modern microwave amplifiers, as well as for research and analysis of the efficiency of existing devices.

Racket Shape Textile Antenna for Triple-Band Frequency Applications

The chapter explores a racket shaped antenna that operates in triple band frequency configuration. The main advantage of this antenna is that the design uses wearable textile material as a substrate. Here, jeans material is used as a substrate whose dielectric constant is 1.7 and thickness is 1mm. The designing and simulation are done with the help of CST software. The anticipated antenna operates in C-band and X-band providing three resonant frequencies 7.335GHz, 8 GHz, and 8.38 GHz. Different analyses have been done using CST software based on parameters like return loss, radiation pattern, smith chart, polarization, etc. For obtaining the best result, parametric study has also been done by varying the geometry of the design.

Analysis of Fundamental Differences between Capacitive and Inductive Impedance Matching for Inductive Wireless Power Transfer

Inductive and capacitive impedance matching are two different techniques optimizing power transfer in magnetic resonance inductive wireless power transfer. Under ideal conditions, i.e., unrestricted parameter ranges and no loss, both approaches can provide the perfect match. Comparing these two techniques under non-ideal conditions, to explore fundamental differences in their performance, is a challenging task as the two techniques are fundamentally different in operation. In this paper, we accomplish such a comparison by determining matchable impedances achievable by these networks and visualizing them as regions of a Smith chart. The analysis is performed over realistic constraints on parameters of three different application cases both with and without loss accounted for. While the analysis confirms that it is possible to achieve unit power transfer efficiency with both approaches in the lossless case, we find that the impedance regions where this is possible, as visualized in the Smith chart, differ between the two approaches and between the applications. Furthermore, an analysis of the lossy case shows that the degradation of the power transfer efficiencies upon introduction of parasitic losses is similar for the two methods.

A “La” Shape Antenna for High Frequencies Applications

In this chapter, a ‘ला' shape antenna for high frequencies is designed which has been simulated under CST software using copper material (i.e., FR-4). The dielectric constant of this material is 4.4. The return loss of ‘ला' shaped antenna is -28 dB at 6.774 giga-hertz and -19 dB at 7.7 GHz resonant frequencies. It covers the bandwidth from 6.555 GHz to 7.122 GHz and 7.38 GHz to 8.07 GHz. In this chapter, simulated results like polarization, smith chart, return loss graph, 2-D pattern, 3-D pattern, and polar plot are presented.