Miniature microwave filters for communication systems

This paper presents new developments in miniature integrated microwave filters suitable for application in mobile communication handsets, wireless LAN´s and microwave fixed links. Recent measured results for active microwave filters are presented with emphasis on their nonlinear behavior. The use of high permittivity ceramic substrates in parallel plate TEM mode stripline filters is described and recent measured results are presented for a prototype 2-GHz filter occupying a volume of 0.5-cubic centimeters. E-Plane filters for millimeter wave applications are discussed and measured results are presented for a novel E-Plane filter with asymmetric frequency response which was realized in a planar structure. Finally, a new type of ceramic loaded E-Plane filter is proposed