High-Frequency Characterization ofPrinted CPW Lines onTextiles using aCustomTestFixture

evaluated inthis research, butarebeyondthescopeofthis A screen printer isusedtoprint conductive inks, loadedpaper. withsilver particles, on nonwoventextiles substrates. To TestFixture forHigh-Frequency Characterization evaluate this technology foruseasflexible interconnects; a Inorder toaccurately measure thecharacteristics ofCPW customtestfixture was designed toassist inthehigh lines printed ontextile substrates, wefounditwasnecessary frequency characterization ofCPW transmission lines. Dueto todevelop atest fixture tomechanically support thesample theflexible nature oftextile substrates itisnecessary tohave andallowforhigh-frequency probestobe landedina mechanical support atthepoints ofelectrical contact.repeatable manner. Thistestfixture should notalter the However,thetestfixture mustnotalter theelectrical characteristics ofthedevice undertest (DUT). Thetest fixture characteristics oftheCPW lines. Thistest fixture removesthe wasmadefroma 8.3mmthickacrylic substrate thatis electrical effects ofthemechanical support, andprovides a machined tocreate a voidbeneath theCPW lines. The simple andrepeatable methodology forevaluating variousopening orvoidwasmachined slightly shorter inlength to typesoftextiles substrates, conductive inks, geometrical provide asmall region ofmechanical support onbothends. variations, andother parameters. Time-domain reflectometry Thissmall region alsoprovides astable region toprobethe (TDR)isusedtomeasurethecharacteristic impedance of CPW lines. Figure 1aillustrates thetopandside viewsofthe samples across geometrical variations inthe10cmlong CPW test fixture andtheportion ofmaterial that wasremoved to lines. A comparison showing theeffects ofthemeasuring the create avoidthat thetextile substrate spans. samples using thetestfixture tomeasuring thesamples ona Since anymaterial inclose proximity wouldalter theCPW solid acrylic substrate, andametal plate arepresented. line's electrical behavior, theremoval ofthematerial from