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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-AU link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>Yeah, bugger – that’ll kill it! :-D<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>I looked at the detail, and there’s actually a peak for oxygen absorbtion smack on 60GHz – that’s why they open that band up for class license no doubt ;)<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>It looks like it is ‘only’ about 11dB though, but that’s still easily enough to put a dampner on that idea ;)<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>(good article about all that here: https://transition.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet70/oet70a.pdf)<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Nonetheless, It’s still an interesting alternative to 24GHz :)<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Cheers!<br><br>Mike.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='color:windowtext;mso-fareast-language:EN-AU'>From:</span></b><span lang=EN-US style='color:windowtext;mso-fareast-language:EN-AU'> Tony Langdon [mailto:vk3jed@vkradio.com] <br><b>Sent:</b> Wednesday, 5 August 2015 7:25 PM<br><b>To:</b> mw@freenet.net.au<br><b>Cc:</b> melbwireless-bounces@lists.wireless.org.au<br><b>Subject:</b> Re: [MLB-WIRELESS] New Lightpointe product<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>On 5/08/2015 7:18 PM, <a href="mailto:mw@freenet.net.au">mw@freenet.net.au</a> wrote:<span style='font-size:12.0pt;mso-fareast-language:EN-AU'><o:p></o:p></span></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoPlainText><span style='color:#1F4E79'>Hey Tony,</span><o:p></o:p></p><p class=MsoPlainText><span style='color:#1F4E79'> </span><o:p></o:p></p><p class=MsoPlainText><span style='color:#1F4E79'>I thought so too until I took a look at the LIPD docs:<br><br><br></span><o:p></o:p></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=595 style='width:446.25pt;background:white;border-collapse:collapse'><tr><td width=47 valign=top style='width:35.5pt;padding:0cm 5.35pt 0cm 5.35pt'><p class=MsoNormal align=right style='mso-margin-top-alt:auto;margin-right:5.65pt;margin-bottom:6.0pt;text-align:right'>51<o:p></o:p></p></td><td width=132 valign=top style='width:99.25pt;padding:0cm 5.35pt 0cm 5.35pt'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Data communications transmitters used outdoors<o:p></o:p></p></td><td width=151 valign=top style='width:4.0cm;padding:0cm 5.35pt 0cm 5.35pt'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>59000–63000<o:p></o:p></p></td><td width=95 valign=top style='width:70.9pt;padding:0cm 5.35pt 0cm 5.35pt'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>150 W<o:p></o:p></p></td><td width=170 valign=top style='width:127.5pt;padding:0cm 5.35pt 0cm 5.35pt'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:15.9pt'>1. Transmitters are limited to land and maritime deployments.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:15.9pt'>2. Maximum transmitter power must be 20 mW or less.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:15.9pt'>3. Spurious emissions outside the band must be less than ‑30dBm/MHz.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:6.0pt;margin-left:14.45pt'>4. For outdoor use only.<o:p></o:p></p></td></tr></table><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>According to this detail, max EIRP is 52dBm which means that 8 dBm max tx capability with 47dBi antenna still comes in under the regulatory limits.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>According to free space attenuation calculator (here <a href="http://www.radio-electronics.com/info/propagation/path-loss/free-space-formula-equation.php">http://www.radio-electronics.com/info/propagation/path-loss/free-space-formula-equation.php</a>) 60GHz over 10km is only 146dB, so if that lightpointe gear can run at full 55dBm EIRP, then result at the receiver (assume 47dBi antenna) will be up to around -47 which will surely be sufficient for a decent link :)</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>Tell you what, though, 0.6 degree antenna beam will make it damn tricky to align, and to KEEP aligned when there is a lot of heat fluctuation in the air ;)</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>But even with the 44dBi antenna, it only adds 18dB to the calculations, and -65 over 10km is still pretty good….</span><o:p></o:p></p></blockquote><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Times New Roman",serif;mso-fareast-language:EN-AU'>Did you include the additional 16dB/km of Oxygen absorption loss? That's on top of normal 1/R^2 free space losses. So, there's 160dB of absorption loss from oxygen in the atmosphere over a 10k path. Hmm, 300dB path loss, that's worse than VHF moonbounce (~270dB)! :) <br><br><br><o:p></o:p></span></p><pre>-- <o:p></o:p></pre><pre>73 de Tony VK3JED/VK3IRL<o:p></o:p></pre><pre><a href="http://vkradio.com">http://vkradio.com</a><o:p></o:p></pre></div></div></body></html>