Rotman lens for the millimeter wave frequency range

Applications in radar system and communications systems require very often antennas with beam steering or multi beam capabilities. For the millimetre frequency range Rotman lenses can be useful as multiple beam forming networks for linear antennas providing the advantage of broadband performance. For microwave bands lens design is predominantly performed in stripline or microstrip technology to meet the requirements for compact low weight and low costs systems. The design and development of Rotman lens at 94 GHz feeding an antenna array for beam steering applications is presented. The construction is completely realized in waveguide technology. Experimental results are compared with theoretical considerations and electromagnetic simulations. The first approach for a two dimensional lens stack for 94 GHz is demonstrated.