Comments on: OpenWRT on a D-Link DIR-300 http://www.villagetelco.org/2008/11/openwrt-on-a-dlink-dir300/ an easy-to-use, scalable, standards-based, wireless, local, do-it-yourself, telephone company toolkit Wed, 14 Jul 2010 17:54:23 +0000 hourly 1 http://wordpress.org/?v=abc By: Elektra http://www.villagetelco.org/2008/11/openwrt-on-a-dlink-dir300/comment-page-1/#comment-336 Elektra Sat, 05 Sep 2009 15:19:54 +0000 http://www.villagetelco.org/?p=88#comment-336 The Atheros AR2317 chip features receiver-only diversity, so we obviously have got two RF ports on the chip and one port is RX only. According to D-Link the external antenna port of the DIR-300 has a receiver sensitivity of -89dBm @ 1Mbit. Since the antenna port is connected to the TX/RX port of the chip you are experiencing additional losses on the TX/RX port from a chip-internal switch that must switch between TX and RX. This switch is needed in every transceiver to stop transmitter power from entering the receiver. This switch adds some losses and hence reduces the RX sensitivity to some degree compared to the RX-only port. I don't know the receiver sensitivity of the TX/RX port of the AR2317, so I could place only a wild guess here about the differences introduced by the switch - maybe 3dB? Also I don't know how well the RF frontend design and components of the DIR-300 work. As usual in the industry manufacturers of such a cheap off-the-shelf product will try to minimize cost and will put cost over performance. -89dBm @ 1Mbit is not industry-leading performance but it is OK-ish for a SOHO product. The best WiFi radios I know offer -97dBm @ 1Mbit receiver sensitivity according to the manufacturer data sheets (the class of 100USD long range mPCI cards from Ubiquiti et al.) The Atheros AR2317 chip features receiver-only diversity, so we obviously have got two RF ports on the chip and one port is RX only. According to D-Link the external antenna port of the DIR-300 has a receiver sensitivity of -89dBm @ 1Mbit. Since the antenna port is connected to the TX/RX port of the chip you are experiencing additional losses on the TX/RX port from a chip-internal switch that must switch between TX and RX. This switch is needed in every transceiver to stop transmitter power from entering the receiver. This switch adds some losses and hence reduces the RX sensitivity to some degree compared to the RX-only port. I don’t know the receiver sensitivity of the TX/RX port of the AR2317, so I could place only a wild guess here about the differences introduced by the switch – maybe 3dB? Also I don’t know how well the RF frontend design and components of the DIR-300 work. As usual in the industry manufacturers of such a cheap off-the-shelf product will try to minimize cost and will put cost over performance. -89dBm @ 1Mbit is not industry-leading performance but it is OK-ish for a SOHO product. The best WiFi radios I know offer -97dBm @ 1Mbit receiver sensitivity according to the manufacturer data sheets (the class of 100USD long range mPCI cards from Ubiquiti et al.)

]]> By: z22 http://www.villagetelco.org/2008/11/openwrt-on-a-dlink-dir300/comment-page-1/#comment-335 z22 Fri, 04 Sep 2009 16:12:09 +0000 http://www.villagetelco.org/?p=88#comment-335 The DIR-300 is great for its price but I recently did some tests: http://forum.openwrt.org/viewtopic.php?id=21504 The RP-SMA port is getting 5 dB less than the internal antenna, the internal antenna is unable to transmit (so you could not hack a coax to the internal antenna trace to use a higher gain antenna). I hope someone could check this. The DIR-300 is great for its price but I recently did some tests: http://forum.openwrt.org/viewtopic.php?id=21504
The RP-SMA port is getting 5 dB less than the internal antenna, the internal antenna is unable to transmit (so you could not hack a coax to the internal antenna trace to use a higher gain antenna). I hope someone could check this.

]]> By: Steve http://www.villagetelco.org/2008/11/openwrt-on-a-dlink-dir300/comment-page-1/#comment-68 Steve Tue, 02 Dec 2008 07:20:00 +0000 http://www.villagetelco.org/?p=88#comment-68 I think this may come down to global supply chains. See here (http://tinyurl.com/dir-300) the DLink DIR-300 at amazon.co.uk for 22.95 GBP or about 35 USD. Amazon.co.uk sell the WRT54GL for about 45 GBP or about 68 USD http://tinyurl.com/wrt54gl-router. I think this may come down to global supply chains. See here (http://tinyurl.com/dir-300) the DLink DIR-300 at amazon.co.uk for 22.95 GBP or about 35 USD. Amazon.co.uk sell the WRT54GL for about 45 GBP or about 68 USD http://tinyurl.com/wrt54gl-router.

]]> By: Charles N Wyble http://www.villagetelco.org/2008/11/openwrt-on-a-dlink-dir300/comment-page-1/#comment-66 Charles N Wyble Mon, 01 Dec 2008 18:32:38 +0000 http://www.villagetelco.org/?p=88#comment-66 I'm not sure how one arrives at the conclusion that the DIR-300 is 1/2 price of the linksys. Amazon: Linksys wrt54gl (around 50.00) http://adjix.com/gtqm D-Link dir-300 (around 100.00) http://adjix.com/gtqn I’m not sure how one arrives at the conclusion that the DIR-300 is 1/2 price of the linksys.

Amazon:

Linksys wrt54gl (around 50.00) http://adjix.com/gtqm
D-Link dir-300 (around 100.00) http://adjix.com/gtqn

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