GPS World, August 2012

Infrastructure TIMING SKDVH DQJOH RIIVHW RI R KDV DOVR EHHQ LQWURGXFHG LQ D PDWWHU RI PLQXWHV V H SHFWHG WKHUH LV D PDUNHG GLIIHUHQFH LQ WKH SKDVRUV RQ WKH 6 QFKURZDYH VFUHHQ 7KH RVFLOORVFRSH DOVR VKRZV D WLPH RIIVHW RI V KDV EHHQ LQGXFHG LQ WKH YLFWLP UHFHLYHU FIGURE 8 VKRZV SLFWXUHV RI WKH RVFLOORVFRSH DQG WKH 6 QFKURZDYH VFUHHQ DW DERXW VHFRQGV LQWR WKH WHVW W WKLV SRLQW WKH VSRRIHG VLJQDO ZDV KHDYLO DWWHQXDWHG DQG LQVWDQWO UHDOLJQHG ZLWK WKH DXWKHQWLF VLJQDOV 7KLV ZDV LQWHQGHG WR EH WKH HQG RI WKH WHVW EXW ZKHQ WKLV SDUWLFXODU UHFHLYHU ORVW ORFN RQ WKH VLJQDO LW FRQWLQXHG WR VHQG RXW D YDOLG WLPH VLJQDO WR WKH 308 ZKLOH IO ZKHHOLQJ RII LWV LQWHUQDO FORFN 7KLV FDXVHG DQ DODUP WR LVVXH RQ WKH IURQW SDQHO RI WKH WLPH UHIHUHQFH UHFHLYHU LQGLFDWLQJ ORVV RI 36 VLJQDO ORFN 7KH GRZQVWUHDP 308 KRZHYHU ZDV REOLYLRXV WR WKLV ORVV RI ORFN 7KLV VWDWH SHUVLVWHG IRU DERXW KDOI DQ KRXU EHIRUH WKH FORFN ILQDOO UHDFTXLUHG WKH DXWKHQWLF VLJQDO DQG LQVWDQWO UHDOLJQHG LWV WLPH RXWSXW ZKLFK FDXVHG WKH SKDVRUV WR UHDOLJQ LJXUH GRHV QRW VKRZ WKH SKDVH DQJOH GDWD IRU WKLV HQWLUH SHULRG EXW GRHV VKRZ WKDW WKH SKDVH DQJOH GLIIHUHQFH H FHHGV DW OHDVW R EHIRUH WKH WLPH UHIHUHQFH UHFHLYHU UHDFTXLUHV WKH DXWKHQWLF VLJQDO Implications 6 QFKURSKDVRU GDWD SURYLGHV D FOHDU SLFWXUH RI WKH VWDWH RI WKH SRZHU V VWHP LQ UHDO WLPH V WKH VL H RI WKH SRZHU JULG JURZV DQG VWDELOLW PDUJLQV DUH UHGXFHG WR SURYLGH PRUH HIILFLHQW GLVWULEXWLRQ RI SRZHU LW ZLOO EHFRPH GHVLUDEOH WR XVH V QFKURSKDVRUV IRU FRQWURO SXUSRVHV 308 PDQXIDFWXUHUV DUH FXUUHQWO VHOOLQJ 308V FDSDEOH RI LPSOHPHQWLQJ DXWRPDWHG FRQWURO VFKHPHV WKDW RIIHU UHVSRQVH WLPHV OHVV WKDQ F FOHV 6XFK VZLIW UHVSRQVH WLPHV DUH VHHQ DV QHFHVVDU WR SUHYHQW JULG LQVWDELOLW RU GDPDJH WR HTXLSPHQW RQWURO VFKHPHV EDVHG RQ V QFKURSKDVRUV UHO RQ SKDVH DQJOH GLIIHUHQFHV EHWZHHQ WZR QRGHV DV DQ LQGLFDWRU RI D IDXOW FRQGLWLRQ 2QH FIGURE 4 Oscilloscope left and Synchrowave right screen at the start of the test which is marked as point 1 in Figure 3 FIGURE 5 Oscilloscope and Synchrowave screen at about 620 seconds point 2 in Figure 3 FIGURE 6 Oscilloscope and Synchrowave screen at about 680 seconds point 3 in Figure 3 H DPSOH RI D FXUUHQWO RSHUDWLRQDO V QFKURSKDVRU EDVHG FRQWURO V VWHP LV WKH KLFRDVHQ QJRVWXUD WUDQVPLVVLRQ OLQN LQ 0H LFR 7KLV WUDQVPLVVLRQ OLQH OLQNV WRJHWKHU ODUJH K GURHOHFWULF JHQHUDWRUV LQ JRVWXUD WR ODUJH ORDGV LQ KLFRDVHQ WKURXJK WZR N9 WUDQVPLVVLRQ OLQHV DQG RQH N9 WUDQVPLVVLRQ OLQH I D IDXOW RFFXUV LQ ZKLFK ERWK RI WKH N9 OLQHV DUH ORVW WKHQ WKH K GURHOHFWULF JHQHUDWRUV PD H SHULHQFH DQJXODU LQVWDELOLW Q RUGHU WR SUHYHQW WKLV D 308 ZDV VHW XS DW HDFK HQG RI WKH WUDQVPLVVLRQ OLQHV ZLWK D GLUHFW FRPPXQLFDWLRQV OLQN EHWZHHQ WKHP W ZDV IRXQG WKDW XQGHU QRPLQDO DQG VLQJOH IDXOW RQO RQH N9 OLQH ORVW FRQGLWLRQV WKH SKDVH DQJOH GLIIHUHQFH EHWZHHQ WKH WZR ORFDWLRQV ZDV OHVV WKDQ R ZKHUHDV D GRXEOH IDXOW ERWK N9 OLQHV ORVW SURGXFHG D SKDVH DQJOH GLIIHUHQFH RI R DVHG RQ WKLV ILQGLQJ WKH 308V ZHUH FRQILJXUHG VR WKDW LI WKH SKDVH DQJOH GLIIHUHQFH H FHHGHG R WKH K GURHOHFWULF JHQHUDWRUV ZRXOG EH DXWRPDWLFDOO WULSSHG I D VSRRIHU ZHUH WR DWWDFN WKLV V VWHP LQ 0H LFR RU D VLPLODU LPSOHPHQWDWLRQ HOVHZKHUH WKHQ WKH VSRRIHU FRXOG FDXVH www gpsworld com August 2012 GPS World 37