Virtual measurement system for UHF-transistor amplifiers

Introduction. Measurement systems for research of telecommunication devices and of their elements are difficult to maintain and expensive. Therefore when possible, its may be replaced by virtual measurement systems (VMS), which allow one to perform measurements based on physical parameters of testing device.

Aim. VMS development for measuring of amplifiers parameters by means of simulation modeling based on amplifier topology.

Methods and materials. VMS is to be used for research of a small signal amplifier (a part of transceiver). It consists of program modules and graphic interface, realized by LabVIEW. The program part contains text modules in LabVIEW syntax, which calculate S-parameters frequency dependencies for an amplifier. For definition of parameters amplifier circuit by a decomposition technique is being split into sequential two-port net-works, which can be described by corresponding matrixes. After determination of frequency dependent matrixes elements, the matrixes are being converted and multiplied. It allows one to obtain frequency dependencies of parameters of an amplifier. VMS interface is a 3-D-rendered on a computer screen front panel of a virtual vector network analyzer with a device under test connected to its test ports.

Results. VMS for UHF-amplifiers research based on given topology was described. The calculations of amplifier transmission lines and amplifier in the whole parameters based on corresponding matrixes and their conversions were presented. The algorithm of a measuring system operation was described. 3D measuring complex and objects under test visualization were shown. The comparison with existing software for design and simulation of UHF-devices such as Microwave Office was realized.

Conclusions. Contrary to Microwave Office, aimed to solution of synthesis tasks, VMS is aimed to research tasks. It has a realistic visualization of measurement devises and simple parameters input, do not need big computer resources and is free. VMS can be used in educational process, especially for online education, when using of Microwave Office is impossible.

1. Network analyzers. Available at: https://www.keysight.com/ru/pcx-x2015001/network-analyzers (accessed 11.05.2019) . (In Russ.)

2. Vector Network Analyzers. Available at: https://www.rohde-schwarz.com/ru/products/test-and-measurement/network-analyzers/pg_overview_64043.html (accessed 11.05.2019). (In Russ.)

3. Rosenberger Online Product Catalog. Available at: https://catalog.rosenberger.com/ (accessed 11.05.2019).

4. Cables. Available at: https://ecatalog.hubersuhner.com/category/E-Catalog/Radio-frequency/Cables (accessed 11.05.2019) .

5. Virtual Analyzer - Virtual Measuring Complex. Pt. 1. Available at: https://www.rlocman.ru/review/article.html?di=148576 (accessed 11.05.2019). (In Russ.)

6. Virtual Stands and Laboratories. Available at: http://labstand.ru/virtualnye_stendy (accessed 11.05.2019). (In Russ.)

7. Nikolsky V. V., Nikolskaya T. A. Dekopozitsionnyi podhod k zadacham elektrodinamiki [Decomposition Approach to Problems of Electrodynamics]. LENAND (URSS), 2019, 304 p. (In Russ.)

8. Microwave Devices, Circuits and Subsystems for Communications Engineering. Ed. by I. A. Glover, S. R. Pennock, P. R. Shepherd. John Wiley & Sons, 2005, 531 p. doi: 10.1002/0470012757

9. Edwards T. C., Steer M. B. Foundations of Interconnect and Microstrip Design. 3rd ed. John Wiley & Sons, 2000, 512 p. doi: 10.1002/9781118894514

10. David Pozar. Microwave Engineering. 4th ed. John Wiley & Sons, 2011, 752 p.

11. Travis J., Kring J. LabVIEW for Everyone: Graphical Programming Made Easy and Fun. 3rd ed. Crawfordsville, Prentice Hall, 2007, 1236 p.

12. Polovko A. M,. Butusov P. N. Interpoliatsiya. Metody i kompiuternye tehnologii ih realisazii [Interpolation. Methods and Computer Technologies of Implementation]. SPb, BHV-Peterburg, 2004, 320 p. (In Russ.)

13. LabVIEW 2018 Help. Formula nodes. Available at: http://www.ni.com/pdf/manuals/371361r.zip (accessed 11.05.2019).

14. Evdokimov Y., Lindval V., Scherbakov G. LabVIEW dlya radioinzhenera. Ot virtualnoi modeli do realnogo pribora [LabVIEW for Radioengineer. From Virtual Model to Real Device]. DMK, 2007, 400 p. (In Russ.)

15. Blume P. The LabVIEW Style Book. 1st ed. Prentice hall, 2007, 400 p.

16. SweetHome3D. Available at: http://www.sweet-home3d.com (accessed 11.05.2019).

17. Steer M. Microwave and RF Design: A Systems Approach. 2nd ed. SciTech Publishing, 2013, 1194 p.