Matched X-band magic T coupler
The present example considers X-band magic T coupler with matching elements.
X-band magic T coupler with matching elements.
Project of X-band magic T coupler with matching elements in QW-Modeller.
The structure is a model of X-band magic T (or magic tee or hybrid tee) coupler with matching elements.
The magic T consists of four rectangular waveguides (WR90 22.86 x 10.16 mm) meeting in a single junction. To minimise return losses of magic T arms, matching post and iris are placed inside the junction. The ports are located inside the arms, behind the flanges. The FDTD mesh is limited to active areas only (flanges are not included) to make scenario as compact as possible.

The ports for S-parameters extraction are numbered as follows:
[1] - Input port
[2] - Output port
[3] - Arm H port
[4] - Arm E port

The S-Parameters postprocessing is set from 8 GHz to 12 GHz with the frequency step of 0.01 GHz.
The postprocessing will calculate full S-matrix (Smn option). It will be calculated in Multi simulator regime, which calculates all the matrix parameters simultaneously.
S-Parameters postprocessing configuration dialogue.
S-parameters results for excitation from Input port [1].
In the frequency band 9-11GHz, transmission to arm E (port [4]) and arm H (port [3]) is close to -3dB. It can be noticed that the collinear Output port [2] is isolated.
S-parameters results for excitation from Input port [1].
Signal is 180o out of phase between port [3] and port [4].

Time-dependent electric field distribution at 10GHz, with excitation from Input port [1]. Signal is divided equally between port [3] and port [4]. Port [2] is isolated.