A novel design of E-plane bandstop waveguide filter using quarter-wave resonators

摘要

Anoveldesignofsecond-orderE-planebandstopwaveguidefilterispresentedinthispaper.Itisbasedontheuseofproperlyshapedquarter-waveresonatorsandacouplingelementinaformofsplit-ringresonator.Actually,quarter-waveresonatorsareimplementedasmainresonatingelements,whilethesplit-ringresonatorisprimarilyusedtofine-tunetherejection-band.Simpledesignisproposedusingsingleprinted-circuitinsert,placedintheE-planeofthestandardWR-90rectangularwaveguide.TheobtainedfilterisintendedtooperateinX-frequencyband,itscentralfrequencyissetto10nbsp;GHz,whilethebandwidthisnearly680nbsp;MHz.Filterresponseisinvestigatedforvariouspositionsoftheresonators,thuselaboratingontheeffectsarisingfromthechangeoftheirpositions.Thevariationofthebandwidthisalsoexplained,regardingthemutualdistancebetweenthequarter-waveresonatorsandthepresenceofthecouplingelement.Theexperimentalverificationoftheproposeddesignisprovided,aswell.