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<html> <head> <title>RFID-Bulletin Board: Re: max. antenna dimension for 13.56MHz, Koos Fockens at 8/13/2001 09:23</title> <!-- Anfang Header --><!-- Ende Header --> </head> <BODY BGCOLOR="#fffcf4"><!-- Anfang BeitragsseitenKopf --><!-- Ende BeitragsseitenKopf --><!-- AnfangBanner --><!-- EndeBanner --><blockquote> <center> <h1>Re: max. antenna dimension for 13.56MHz</h1> </center><!-- Anfang BeitragsNavigationsLeisteOben --><!-- AnfangLinie --><center><p><HR></p></center><!-- EndeLinie --><center><P><B>[ <a href="../index.htm">RFID-Bulletin Board</a> ]</B></P></center><!-- AnfangLinie --><center><p><HR></p></center><!-- EndeLinie --><!-- Ende BeitragsNavigationsLeisteOben --><p>Written by <a href="mailto:kf@nedap.nl">Koos Fockens</a> at 13 Aug 2001 09:23:57:<p>As an answer to: <a href="437.htm">max. antenna dimension for 13.56MHz</a> written by Reinier Gerritsen at 10 Aug 2001 12:46:57:<p>>"The length of any antenna loop element shall be < lamda/4 or <30 m wichever is shorter"<br>>For 13.56 MHz, lambda/4 = 5.5 m. Question: what is an "antenna loop element?" Is it the length or width of the antenna, or total antenna wire length (perimeter)? Can I make a loop antenna as big as 5.5 x 5.5 meter, or is it only 1.25 x 1.25 meter?<p>With "antenna loop" is meant the total length of one closed loop.<br>This is because a larger loop cannot be tuned with a single serial capacitor, and because <br>a larger loop antenna will not only radiate as a magnetic loop but also as an electrical antenna.<p>This means that for larger loops you arrive in class 7.1.3 "Other transmitters".<br><br><!-- AnfangLinie --><center><p><HR></p></center><!-- EndeLinie --><form method=POST action="../wwwforum.cgi?formular"><input type=hidden name="followup" value="437,438"><input type=hidden name="origname" value="Koos Fockens"><input type=hidden name="origemail" value="kf@nedap.nl"><input type=hidden name="origsubject" value="Re: max. antenna dimension for 13.56MHz"><input type=hidden name="origdate" value="13 Aug 2001 09:23:57"><input type=hidden name="subject" value="Re: max. antenna dimension for 13.56MHz"><input type="submit" name="abschicken" value="Write an answer"> <br><!-- AnfangLinie --><center><p><HR></p></center><!-- EndeLinie --><p><a name="followups"><B>List of answers:</B></a><br><ul><!--insert: 438--></ul><!--end: 438--><!-- Anfang BeitragsNavigationsLeisteUnten --><!-- AnfangLinie --><center><p><HR></p></center><!-- EndeLinie --><center><P><B>[ <a href="../index.htm">RFID-Bulletin Board</a> ]</B></P></center><!-- AnfangLinie --><center><p><HR></p></center><!-- EndeLinie --><!-- Ende BeitragsNavigationsLeisteUnten --></blockquote><!-- Anfang BeitragsseitenFuss --><!-- Ende BeitragsseitenFuss --></body></html>⌨️ 快捷键说明
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