Non-focal microwave lens design with optimization of phase errors and amplitude performance

Abstract

A symmetry design model for 77 microstrip nonfocal Rotman lens is presented with a precise behavior of phase errors and amplitude performance. Methods for optimizing show average phase errors of 2.1 degree and average amplitude errors of 1.8 dB along the input ports of array elements. Array factor of the lens shows less than 2 degree deviation along the 90 degree scanning and shows good amplitude tapering at all excitation ports.

Rotman lens design and optimization for 5G applications

“…In [3], a non-focal design scheme was applied to produce minimum average phase errors for all beam ports, rather than achieving zero-phase error for only selected focal points. In [18], the symmetry of non-focal lens is introduced, so that the input ports and output ports can be interchangeable. In [19], the phase errors are minimized by finding the optimal values of off-center focal angle ( α ), On-axis focal length ( f ) and ray to beam angle ratio ( γ ) and moving off-axis focal points along a beam curve.…”

Optimisation and implementation for a non‐focal Rotman lens design

“…When the number of output ports increases, the phase error will also arose. Researchers have proposed several methods to reduce the phase error [16][17][18][19][20]. In the published work by Dong [19] at 2010, a non-focal method for designing and optimising the phase error has been reported.…”