Modelling of power combiner using fractional order derivative

Combining is a requirement in many applications, large number have been proposed since using different design approaches and transmission media. The aim was to combine separate signal sources into a stronger signal or to combine by improving the power level of the individual signal source. One of the most important structure in many applications, transmission line transformer (TLT) used among, provide broadband functionality from low to very high frequencies for large number of applications. By using a TLT between, a configuration compatible with it, a modelling of two-way power combiner using fractional elements is introduced. The proposed combiner operates from 3 MHz to 3 GHz. The structure is implemented in a broadband circuit with an ideal transformer. The proposed circuit is studied analytically and obtained with physical dimensions within HFSS (High-Frequency Structural Simulator). To extract the equations governing the overall structure, the proposed power combiner was assumed by its equivalent circuit model including input source voltages with resistance at the input ports separated by two times the same resistance and two times lower the same resistance at the output port. Furthermore, the equivalent circuit model with the transmission line is defined with the initial conditions required throughout the design process of the proposed structure. With broadband model equivalent circuit implementation, the transmission parameters were evidenced in MATLAB while in HFSS, the EM (Electromagnetic) analysis give some aspect of the reflection and the transmission characteristics of the designed power combiner-based in range of interest. The input reflection coefficients achieved a maximum of 2dB with a slight increase over some frequencies in the range of interest while the output reflection coefficient provides a maximum of 7dB. On the other hand, transmission characteristics are also simulated and consistent results are observed. From this, the designed combiner achieved an input isolation of 22dB maximum and a gain of 3dB. The quality of our work and his performance were highlighted by the co-simulation MATLAB/HFSS results by considering the fractional order transmission line compared with the classical one. The one investigated in this thesis provide a trade-off in term of accurate results. Additionally, it allows and gives more control through the order of derivative. In addition, the skin effect is modelled in the analysis of the proposed structure as well and the response of the power combiner shows no effect in the simulated results.