Folded Rotman lens multibeam antenna in SIW technology at 24 GHz

We introduce here a new dual-layer multibeam antenna with a folded Rotman lens used as a compact beam forming network in SIW technology. The objective is to reduce the overall size of the antenna system by folding the Rotman lens on two layers along the array port contour and using a transition based on an exotic reflector and several coupling vias holes. To validate the proposed concepts, an antenna system has been designed at 24.15 GHz. The radiating structure is a SIW slotted waveguide array made of fifteen resonant waveguides. The simulated results show very good scanning performances over ±47°. It is also demonstrated that the proposed transition can lead to a size reduction of about 50% for the lens, and more than 33% for the overall size of the antenna.

[1]  W. Rotman,et al.  Wide-angle scanning with microwave double-layer pillboxes , 1958 .

[2]  H.A.C. Tilmans,et al.  Design considerations and technology assessment of phased-array antenna systems with RF MEMS for automotive radar applications , 2005, IEEE Transactions on Microwave Theory and Techniques.

[3]  R. Vahldieck,et al.  An LTCC-Based folded Rotman lens for phased array applications , 2006, 2006 Asia-Pacific Microwave Conference.

[4]  Wei Hong,et al.  Millimeter-Wave Substrate Integrated Waveguide Multibeam Antenna Based on the Parabolic Reflector Principle , 2008, IEEE Transactions on Antennas and Propagation.

[5]  W. Hong,et al.  A Double Layer Substrate Integrated Waveguide Blass Matrix for Beamforming Applications , 2009, IEEE Microwave and Wireless Components Letters.

[6]  W. Rotman,et al.  Wide-angle microwave lens for line source applications , 1963 .

[7]  Werner Wiesbeck,et al.  Offset cylindrical reflector antenna fed by a parallel-plate Luneburg lens for automotive radar applications in millimeter-wave , 2003 .

[8]  Li Yan,et al.  Simulation and experiment on SIW slot array antennas , 2004 .

[9]  L. Le Coq,et al.  Multi-Beam Multi-Layer Leaky-Wave SIW Pillbox Antenna for Millimeter-Wave Applications , 2011, IEEE Transactions on Antennas and Propagation.

[10]  J. Butler,et al.  Beam-forming matrix simplifies design of electronically scanned antennas , 1961 .

[11]  R. C. Hansen.  Design trades for Rotman lenses , 1991 .

[12]  Ke Wu,et al.  Planar $Ku$ -Band 4 $\,\times\,$ 4 Nolen Matrix in SIW Technology , 2010 .

[13]  Young Joong Yoon,et al.  Compact Two-Layer Rotman Lens-Fed Microstrip Antenna Array at 24 GHz , 2011, IEEE Transactions on Antennas and Propagation.

[14]  Ronan Sauleau,et al.  Single-Folded Leaky-Wave Antennas for Automotive Radars at 77 GHz , 2010, IEEE Antennas and Wireless Propagation Letters.