Antenna Analysis

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" colspan=2 height=80 BGCOLOR="#000000" TEXT="#F7F7FF" bgproperties="fixed" background="03f00500dvldtc.gif"> <div> <FONT SIZE="5" COLOR="#FFCC66" FACE="Arial" ><B>The Monitoring Post</B></FONT><B>   </B></div> <bR> <DIV ALIGN="LEFT"></DIV> <div> <B> <a href= "http://www.accesscomm.ca/users/monitoringpost/rx2.htm" target="_top"" onMouseOver= "if (document.images) document._31222181150.src= 'http://www.accesscomm.ca/users/monitoringpost/22281150.gif';" onMouseOut= "if (document.images) document._31222181150.src= 'http://www.accesscomm.ca/users/monitoringpost/22181150.gif';"><img src= "http://www.accesscomm.ca/users/monitoringpost/22181150.gif" name="_31222181150" border=0></a>  <IMG SRC="25681150.gif" border=0 width="129" height="21" ALIGN="BOTTOM" HSPACE="0" VSPACE="0">  <a href= "http://www.accesscomm.ca/users/monitoringpost/tips.htm" target="_top"" onMouseOver= "if (document.images) document._58222581150.src= 'http://www.accesscomm.ca/users/monitoringpost/22681150.gif';" onMouseOut= "if (document.images) document._58222581150.src= 'http://www.accesscomm.ca/users/monitoringpost/22581150.gif';"><img src= "http://www.accesscomm.ca/users/monitoringpost/22581150.gif" name="_58222581150" border=0></a>  </B></div> </td> </tr><tr> <td valign="top" width=210 BGCOLOR="#000000" TEXT="#F7F7FF" background="040d2c00dvldtc.gif"> <div>  <img src="HTMLobj-377/aniGif.gif" border="0" align="bottom" width="120" height="58">  </div> <bR> <div>  <a href= "http://www.accesscomm.ca/users/monitoringpost/" target="_top"" onMouseOver= "if (document.images) document._91620281150.src= 'http://www.accesscomm.ca/users/monitoringpost/20181150.gif';" onMouseOut= "if (document.images) document._91620281150.src= 'http://www.accesscomm.ca/users/monitoringpost/20281150.gif';"><img src= "http://www.accesscomm.ca/users/monitoringpost/20281150.gif" name="_91620281150" border=0></a>  </div> <div>  <a href= "http://www.accesscomm.ca/users/monitoringpost/about.htm" target="_top"" onMouseOver= "if (document.images) document._1801fa81150.src= 'http://www.accesscomm.ca/users/monitoringpost/1fb81150.gif';" onMouseOut= "if (document.images) document._1801fa81150.src= 'http://www.accesscomm.ca/users/monitoringpost/1fa81150.gif';"><img src= "http://www.accesscomm.ca/users/monitoringpost/1fa81150.gif" name="_1801fa81150" border=0></a>  </div> <div>  <a href= "http://www.accesscomm.ca/users/monitoringpost/shack.htm" target="_top"" onMouseOver= "if (document.images) document._8481f5581150.src= 'http://www.accesscomm.ca/users/monitoringpost/1f681150.gif';" onMouseOut= "if (document.images) document._8481f5581150.src= 'http://www.accesscomm.ca/users/monitoringpost/1f5581150.gif';"><img src= "http://www.accesscomm.ca/users/monitoringpost/1f5581150.gif" name="_8481f5581150" border=0></a>  </div> <div>  <a href= "http://www.accesscomm.ca/users/monitoringpost/images.htm" target="_top"" onMouseOver= "if (document.images) document._4511f181150.src= 'http://www.accesscomm.ca/users/monitoringpost/1f281150.gif';" onMouseOut= "if (document.images) document._4511f181150.src= 'http://www.accesscomm.ca/users/monitoringpost/1f181150.gif';"><img src= "http://www.accesscomm.ca/users/monitoringpost/1f181150.gif" name="_4511f181150" border=0></a>  </div> <div>  <a href= "http://www.accesscomm.ca/users/monitoringpost/software.htm" target="_top"" onMouseOver= "if (document.images) document._6861ee81150.src= 'http://www.accesscomm.ca/users/monitoringpost/1ef81150.gif';" onMouseOut= "if (document.images) document._6861ee81150.src= 'http://www.accesscomm.ca/users/monitoringpost/1ee81150.gif';"><img src= "http://www.accesscomm.ca/users/monitoringpost/1ee81150.gif" name="_6861ee81150" border=0></a>  </div> <div>  <a href= "http://www.accesscomm.ca/users/monitoringpost/links.htm" target="_top"" onMouseOver= "if (document.images) document._691eb81150.src= 'http://www.accesscomm.ca/users/monitoringpost/1ea81150.gif';" onMouseOut= "if (document.images) document._691eb81150.src= 'http://www.accesscomm.ca/users/monitoringpost/1eb81150.gif';"><img src= "http://www.accesscomm.ca/users/monitoringpost/1eb81150.gif" name="_691eb81150" border=0></a>  </div> <bR> <div> <A HREF="mailto:monitoringpost@accesscomm.ca" TARGET="_top" TITLE="mailto:monitoringpost@accesscomm.ca"><U><B> <img src="HTMLobj-604/aniGif.gif" border="0" align="bottom" width="60" height="50">  </B></U></A></div> <div> <B>Send an E-mail</B></div> <bR> <bR> <bR> <bR> <div> <B>Copyright © 2000 - 2010</B></div> <div> <B>All Rights Reserved</B></div> </td> <td valign="top" height=400 BGCOLOR="#000000" TEXT="#F7F7FF"> <div> Antenna Analysis</div> <div> Since the initial installation of the EB-144, a commercial 2-meter, crossed-loop, omnidirectional antenna, I've attempted to optimize it's reception of a satellite's SNR (signal-to-noise-ratio) by trial and error. This has involved various "tweaks" either to the antenna itself, the receiver or even the type of cabling used.  Of course, the only way to analyze these changes were through the actual processed images - not very scientific.  Although I believe the present configuration is likely the most optimal I've now set about measuring the results - presented here are the initial findings.</div> <bR> <DIV ALIGN="LEFT"></DIV> <div> <TABLE BORDER="1" CELLPADDING="3" CELLSPACING="1" WIDTH="629" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP COLSPAN=2 HEIGHT= 71 WIDTH="611"><div> The two plots below are of the signal-to-noise ratio versus the satellite's observed position. The information is three dimensional in nature with the  <A HREF="javascript:void(0)" ONCLICK="open('snr.htm','miniwin','toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=0,resizable=0,width=300,height=300')">SNR</A>   values shown as either white which can be considered "noise free", yellow as "perceptible noise", green as "noisy" and finally blue as "very noisy" and likely useless.</div> </tD> </tR> <tR> <tD VALIGN=TOP BGCOLOR=#A0A0A4 HEIGHT= 256 ><NOBR><div> <IMG SRC="166fafa0.jpg" border=0 width="250" height="250" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> <tD VALIGN=TOP BGCOLOR=#A0A0A4><NOBR><div> <IMG SRC="168fafa0.gif" border=0 width="250" height="250" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> </NOBR></tD> </tR> <tR> <tD VALIGN=TOP HEIGHT= 53 WIDTH="304"><div> Plot of SNR versus azimuth angle and distance. Radial grid lines are at 500km intervals.</div> </tD> <tD VALIGN=TOP WIDTH="304"><div> Plot of SNR versus azimuth angle and elevation. Radial grid lines are at 10º intervals.</div> </tD> </tR> </TABLE></div> <bR> <div> At first glance my current setup of signal acquisition at 10º elevation produces a fairly uniform signal with perhaps the exception of 30º - 85º azimuth where some noise can be observed between 10º and 20º elevation. As for distance - within a 2000km radius the signal is pretty uniform with noise been introduced on passes outside this radius. These initial plots consist of 65 data sets of the orbits for NOAA 12, NOAA 14 and NOAA 15.</div> <bR> <DIV ALIGN="LEFT"></DIV> <div> The following graphs summarize the performance so the results are more clearly visible.</div> <bR> <div> <IMG SRC="17aa1640.gif" border=0 width="417" height="356" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> <IMG SRC="17ba1640.gif" border=0 width="417" height="356" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <div> <IMG SRC="17ca1640.gif" border=0 width="417" height="356" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> </td> </tr></table></body>