A.Yu. Selyutin

In a printed Rotman lens, the connection points on the front surface are connected to the antenna ports using microstrip lines. The line topology should provide the specified delay and minimum channel loss with maximum isolation between channels. 

The first part contains expressions for calculating the coordinates of the connection points and the normalized lengths of the delay lines. 

The second part describes the general scheme of the proposed topology. Each line consists of four sections: a connection horn, a breeding section, a turning arc and a “sine-square” alignment line. 

In the third part, the equations of the reference curves for each section are given. 

In the fourth part, the parametric equations of the contours of microstrip delay lines and excitation horns are given. A general scheme for constructing the topology of a Rotman lens is proposed.

In the fifth part, the application of the proposed technique is shown using the example of the topology of an 18-channel lens in the 8-18 GHz range.

Selyutin A.Yu. Delay line topology in a printed Rotman lens. Radiotekhnika. 2021. V. 85. № 3. P. 134−147.  DOI: https://doi.org/10.18127/j00338486-202103-14 (In Russian).

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