Rotman Lens Designer®

Rotman Lens Designer (RLD) is a software tool for the design, synthesis, and analysis of Rotman Lenses and their variants. It is based on Geometrical Optics combined with the classical Rotman Lens design equations. It is intended for rapid development and analysis of Rotman Lenses given several physical and electrical input parameters. RLD generates the proper lens contours, transmission line geometry, absorptive port (dummy port) geometry, provides an approximate analysis of performance, and generates geometry files for import into Remcom's XFdtd® for further analysis and fabrication.

RLD Features

RLD creates lens designs based on typical input parameters. An extensive range of output values may be displayed for a given design. Some of the main input and output parameters are listed below.



  • Type of lens - microstrip or stripline

  • Impedance of lines

  • Element spacing on the antenna

  • Number of elements (up to 128)

  • Number of beams (up to 128)

  • Maximum scan angle

  • Off-axis focii angle as a fraction of max scan angle

  • Bandwidth and center frequency

  • Electrical characteristics of lens material - dielectric constant, loss tangent, conductivity and thickness of dielectric material

  • Electrical characteristics of absorber material

  • Physical characteristics of lens - focal length/diameter ratio

  • Aperture distribution

  • Port flare angles


  • Calculation of the lens contour and of the transmission line geometry

  • Element locations along the lens contour

  • Insertion loss (per beam port)

  • Amplitude and phase distributions of the array ports versus frequency

  • Beam to array phase error

  • Beam to array coupling magnitude and phase

  • Beam to array sidewall coupling magnitude

  • Beam to array spillover coupling magnitude

  • Array to beam coupling magnitude and phase

  • Array to beam sidewall coupling magnitude

  • Array to beam spillover coupling magnitude

  • S-parameters for all ports

  • Suggested focal length

  • Number of dummy elements

  • Location of loads on dummy elements

  • Location of absorber if necessary

  • Dimensions, volume

  • Gerber format files may be exported with third-party software

  • XFdtd format files may be exported for full wave analysis

  • Export to SAT format

Learning and Documentation

Application Examples




RLD Overview

RLD Overview


System Requirements

  • Windows 2000 or XP

  • Red Hat Enterprise Linux 4 or higher

  • 1024x768 minimum resolution

  • 64MB or higher OpenGL compliant video card