?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Assessment+of+the+Multipath+Mitigation+Effect+of+Vector+Tracking+in+an+Urban+Environment&rft.creator=Hsu%2C+LT&rft.creator=Groves%2C+PD&rft.creator=Jan%2C+SS&rft.description=Today%2C+smart+mobiles+play+an+important+role+in+our+daily+life.+Most+of+these+devices+are+equipped+with+a+navigation+function+based+on+GNSS+positioning.+However%2C+these+devices+may+not+work+accurately+in+urban+environments+due+to+severe+multipath+interference+and+non-line+of+sight+(NLOS)+reception+caused+by+nearby+buildings.+A+promising+approach+for+reducing+the+effect+of+multipath+interference+and+NLOS+reception+is+vector+tracking+(VT).+VT+is+well-known+for+its+robustness+against+poor+signal-to-noise+levels.+However%2C+its+capability+against+multipath+and+NLOS+has+yet+to+be+determined.+The+new+combination+of+this+paper+is+therefore+to+evaluate+the+performance+of+vector+tracking+in+the+presence+of+multipath+and+NLOS+effects.+A+vector+delay+lock+loop+(VDLL)+is+used+as+the+vector+tracking+technique.+The+noise+tuning+of+the+extended+Kalman+filter+(EKF)+in+vector+tracking+is+a+key+factor+affecting+its+performance.+Therefore%2C+developed+an+adaptive+noise+tuning+algorithm+had+been+based+on+the+measurement+innovation.+In+order+to+evaluate+vector+tracking%E2%80%99s+performance%2C+equivalent+conventional+tracking+loops+are+used+as+a+control.+GNSS+signals+were+collected%2C+while+walking+around+in+a+challenging+urban+environment+subject+to+multipath+interference.+The+experimental+results+show+that+VT+generates+a+more+stable+code+numerical-controlled+oscillator+(NCO)+frequency+than+CT+does.+This+characteristic+could+reduce+the+impact+of+multipath+interference+which+is+reflected+in+a+smaller+position+error+using+VT+during+most+of+run.+To+further+test+capability+of+VT+against+signal+attenuation%2C+this+paper+applies+a+signal+cancellation+method+called+direct+signal+cancellation+algorithm+to+simulate+the+scenario+of+signal+termination+and+NLOS+reception.+According+to+the+simulation%2C+VT+provides+not+only+robustness+against+signal+termination+but+can+also+detect+NLOS+reception+without+any+external+aiding.&rft.publisher=Institute+of+Navigation+Publications&rft.date=2013-04-25&rft.type=Proceedings+paper&rft.language=eng&rft.source=+++++In%3A++Proceedings+of+the+ION+2013+Pacific+PNT+Meeting.++++Institute+of+Navigation+Publications%3A+Honolulu%2C+Hawaii.+(2013)+++++&rft.format=application%2Fpdf&rft.identifier=https%3A%2F%2Fdiscovery.ucl.ac.uk%2Fid%2Feprint%2F1394467%2F1%2FION%2520Pacific%2520PNT%252013.pdf&rft.identifier=https%3A%2F%2Fdiscovery.ucl.ac.uk%2Fid%2Feprint%2F1394467%2F&rft.rights=open