GAP waveguides

Book chapter, 2016

The coming years will show new applications of wireless communications at higher frequencies (30 GHz and above). Modern wireless technologies like massive MIMO and gigabit transmission will become a reality. The industrial winners will be the companies that can provide the hardware at the lowest cost. This requires new waveguide and mmWave packaging technologies that are more cost-effective than normal rectangular waveguide technology and are more power efficient (lower losses) than PCB-based microstrip and coplanar waveguides. The gap waveguide has this potential. The present chapter gives the historical background of gap waveguide technology until its invention in 2008 and how it has evolved since then to include many different kinds of gap waveguide types. Several useful waveguide components have been developed for integration in complete RF front ends. Passive gap waveguide parts and components like filters, couplers, and transitions have been realized very successfully, and active microwave electronics have been packaged. The chapter contains also an overview of the gap waveguide antennas that have been developed during the last years.