A Method for Improving the Technique for the Synthesis of Quasi-two Bandpass Matching Devices

The article deals with issues related to the possibilities of the analytical technique for the synthesis of quasi-two-band matching devices and the way to improve it. The technique is based on the mathematical apparatus of the Generalized Darlington method with the use of a special method of forming quasi-two-band frequency characteristics at the stage of choosing an approximating function. A comparison of the results of load matching obtained using the developed methodology and a progressive numerical synthesis method is presented. The analysis of the solved problem allowed us to make a private assessment of the capabilities of the proposed analytical method of matching. An important limiting circumstance for the synthesis technique is indicated – the lack of solutions for loads of increased complexity, which is caused by a small variability of the known approximating power transfer functions. As a solution to the problem, boundedly flat functions are considered, which differ from classical approximations in their extended variability. The use of a combination of knowledge about the formation of quasi-two-band frequency characteristics and the technique of using limited-flat functions made it possible to expand the range of matched loads. A solution to the test problem of matching a 5-element load is presented, for which the use of classical approximations is not acceptable.

1. Yantsevich M.A., Filippovich G.A. [The metod of synthesis of quasi-dual-band matching device]. Doklady BGUIR = Doklady BGUIR. 2020;2:71-79. (In Russ.)

2. Yantsevich M.A., Filippovich G.A. [Technique for the synthesis of quasi-two-band matching devices]. Izvestiia Gomel'skogo gosudarstvennogo universiteta imeni F. Skoriny = Proceedings of Francisk Scorina Gomel State University. 2021;129:154-158. (In Russ.)

3. Filippovich G.A. [Broadband impedance matching]. Minsk: Military Academy of the Republic of Belarus; 2004. (In Russ.)

4. Caytan О., Bogaert L., Haolin Li, Van Kerrebrouck J., Lemey S., Agneessens S., Bauwelinck J., Demeester P., Torfs G., Vande Ginste D., and Rogier H. Compact and wideband transmit opto-antenna for radio frequency over fiber. Optics Express. 2019;27:8395-8414. DOI: 10.1364/OE.27.008395.

5. Ghorbani A. , Raed A. Abd-Alhameed, Neil J. McEwan, Zhou D. An Approach for Calculating the Limiting Bandwidth-Reflection Coefficient Product for Microstrip Patch Antennas. IEEE Transactions on Antennas and Propagation. 2006;54(4):1328-1331. DOI: 10.1109/TAP.2006.872641.