Wi-Spy Spectrum Analyzer
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From: Jeff Liebermann on 1 Jan 2006 23:45 I've been playing with a Wi-Spy Spectrum Analyzer for a few hours. http://www.metageek.net $99 plus shipping. I installed it on my Panasonic M34 laptop running W2K and did some really crude testing. Some initial comments: 1. It's fairly fast which is a BIG plus. It's much faster and better than my Proxim 7400 card. I set my access point to beacon once every second instead of the usual 10 times per second. It was easily detected but took a few sweeps for wi-spy to coincidentally end up on the same exact frequency as the access point. One can't see the sinx/x DSSS spectra, but it's close enough. 2. It can easily pickup my Panasonic KX-TG2257 2.4GHz cordless phone and microwave oven from anywhere in the house (2 floors). Sensitivity, even with the tiny antenna, is quite impressive. 3. Dynamic range sucks but that's understandable. The noise floor is about -60dBm while the SA saturates at about -32dBm. That's 28dB of dynamic range which is really bad compared to my ancient HP140T spectrum analyzer with about 60dB of dynamic range. However, I would not expect much more from such a unit. What this means is that there will need to be some form of attenuator to deal with close in sniffing, and possibly an adjustable gain amplifier for long range work. I can just barely see my neighbors client radio at about 200ft with a 2dBi antenna and a tangle of wet trees in between. I'm sure that with an external antenna on the wi-spy, it would be detectable. I had my neighbor across the street (about 50ft) fire up their Uniden something 2.4GHz cordless phone. I could see it, but just barely. Again, more antenna gain would be helpful. 4. The software appears to be stable and quite useful. Whomever wrote it apparently has used commercial spectrum analyzers. I had some problems restarting the application after hibernation, but a reboot solved that. I can run my Netgear WG511v2 PCMCIA card at the same time. It makes for an interesting display, especially when the card is scanning for access points. 5. I won't post any AVI recording files until I get a reproducible setup and possibly butcher the unit with a better antenna. The ones on the web site should be sufficient for now. | http://recordings.metageek.net/index.php 6. The display is either by channel number or by frequency. It will display all 14 UK channels, but when set to frequency, it reverts to the 11 US channels (2400 to 2483.5). 7. I couldn't resist taking it apart and analyzing the hardware. It's actually a DSSS wireless mouse receiver. The radio module is made by Unigen: | http://www.unigen.com/product05/W_JUNO/juno_probrief.cfm?part_number=UGQUBE1US I had to apply for permission to download their secret data sheet. Maybe later. Photos at: | http://802.11junk.com/jeffl/pics/wireless/Wi-Spy/index.html The square thing in the picture is a push button, usually used to synchronize a wireless mouse with a USB adapter. The RF chips is a Cypress Semi CYWUSB6934-48LFXC: | http://www.cypress.com/portal/server.pt?space=CommunityPage&control=SetCommunity&CommunityID=209&PageID=259&fid=65&rpn=CYWUSB6934 The antenna is the wiggly affair on the right of: | http://802.11junk.com/jeffl/pics/wireless/Wi-Spy/slides/Wi-Spy-01.html It appears that I can easily attach a small coax pigtail for an external antenna. Of course, the usual coffee can or dish reflector can also be used. Some notes on the antenna design: | http://www.cypress.com/portal/server.pt/gateway/PTARGS_0_2_1289_209_0_43/http;/sjapp20;7001/publishedcontent/publish/design_resources/application_notes/contents/wirelessusb_tm__antenna_design_layout_guidelines___an5032_9.pdf Bottom line is that it works and seems to work well enough. It will need some modifications to attach an external antenna in order to make it suitable for interference detection and location. It may take a while for me to use it in the field (it's raining). However, the fact that it can easily detect my leaky microwave oven and 2.4Ghz cordless phone means that it is sure to be useful. -- Jeff Liebermann jeffl(a)comix.santa-cruz.ca.us 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
From: Rôgêr on 2 Jan 2006 05:48 Jeff Liebermann wrote: > I've been playing with a Wi-Spy Spectrum Analyzer for a few hours. > http://www.metageek.net > $99 plus shipping. I installed it on my Panasonic M34 laptop running > W2K and did some really crude testing. Some initial comments: > > 1. It's fairly fast which is a BIG plus. It's much faster and better > than my Proxim 7400 card. I set my access point to beacon once every > second instead of the usual 10 times per second. It was easily > detected but took a few sweeps for wi-spy to coincidentally end up on > the same exact frequency as the access point. One can't see the > sinx/x DSSS spectra, but it's close enough. > > 2. It can easily pickup my Panasonic KX-TG2257 2.4GHz cordless phone > and microwave oven from anywhere in the house (2 floors). Sensitivity, > even with the tiny antenna, is quite impressive. > > 3. Dynamic range sucks but that's understandable. The noise floor is > about -60dBm while the SA saturates at about -32dBm. That's 28dB of > dynamic range which is really bad compared to my ancient HP140T > spectrum analyzer with about 60dB of dynamic range. However, I would > not expect much more from such a unit. What this means is that there > will need to be some form of attenuator to deal with close in > sniffing, and possibly an adjustable gain amplifier for long range > work. > > I can just barely see my neighbors client radio at about 200ft with a > 2dBi antenna and a tangle of wet trees in between. I'm sure that with > an external antenna on the wi-spy, it would be detectable. > > I had my neighbor across the street (about 50ft) fire up their Uniden > something 2.4GHz cordless phone. I could see it, but just barely. > Again, more antenna gain would be helpful. > > 4. The software appears to be stable and quite useful. Whomever > wrote it apparently has used commercial spectrum analyzers. I had > some problems restarting the application after hibernation, but a > reboot solved that. I can run my Netgear WG511v2 PCMCIA card at the > same time. It makes for an interesting display, especially when the > card is scanning for access points. > > 5. I won't post any AVI recording files until I get a reproducible > setup and possibly butcher the unit with a better antenna. The ones > on the web site should be sufficient for now. > | http://recordings.metageek.net/index.php > > 6. The display is either by channel number or by frequency. It will > display all 14 UK channels, but when set to frequency, it reverts to > the 11 US channels (2400 to 2483.5). > > 7. I couldn't resist taking it apart and analyzing the hardware. It's > actually a DSSS wireless mouse receiver. The radio module is made by > Unigen: > | http://www.unigen.com/product05/W_JUNO/juno_probrief.cfm?part_number=UGQUBE1US > I had to apply for permission to download their secret data sheet. > Maybe later. > > Photos at: > | http://802.11junk.com/jeffl/pics/wireless/Wi-Spy/index.html > The square thing in the picture is a push button, usually used to > synchronize a wireless mouse with a USB adapter. The RF chips is a > Cypress Semi CYWUSB6934-48LFXC: > | http://www.cypress.com/portal/server.pt?space=CommunityPage&control=SetCommunity&CommunityID=209&PageID=259&fid=65&rpn=CYWUSB6934 > > The antenna is the wiggly affair on the right of: > | http://802.11junk.com/jeffl/pics/wireless/Wi-Spy/slides/Wi-Spy-01.html > It appears that I can easily attach a small coax pigtail for an > external antenna. Of course, the usual coffee can or dish reflector > can also be used. Some notes on the antenna design: > | http://www.cypress.com/portal/server.pt/gateway/PTARGS_0_2_1289_209_0_43/http;/sjapp20;7001/publishedcontent/publish/design_resources/application_notes/contents/wirelessusb_tm__antenna_design_layout_guidelines___an5032_9.pdf > > Bottom line is that it works and seems to work well enough. It will > need some modifications to attach an external antenna in order to make > it suitable for interference detection and location. It may take a > while for me to use it in the field (it's raining). However, the fact > that it can easily detect my leaky microwave oven and 2.4Ghz cordless > phone means that it is sure to be useful. Jeff, you're a gentleman and a scholar, I don't care what everybody else says. A $100 SA would be great if it works. Will stay tuned to see what else develops.
From: Rob on 2 Jan 2006 07:28 Jeff Liebermann wrote: > I've been playing with a Wi-Spy Spectrum Analyzer for a few hours. > http://www.metageek.net > $99 plus shipping. I installed it on my Panasonic M34 laptop running > W2K and did some really crude testing. Some initial comments: > > 1. It's fairly fast which is a BIG plus. It's much faster and better > than my Proxim 7400 card. I set my access point to beacon once every > second instead of the usual 10 times per second. It was easily > detected but took a few sweeps for wi-spy to coincidentally end up on > the same exact frequency as the access point. One can't see the > sinx/x DSSS spectra, but it's close enough. > > 2. It can easily pickup my Panasonic KX-TG2257 2.4GHz cordless phone > and microwave oven from anywhere in the house (2 floors). Sensitivity, > even with the tiny antenna, is quite impressive. > > 3. Dynamic range sucks but that's understandable. The noise floor is > about -60dBm while the SA saturates at about -32dBm. That's 28dB of > dynamic range which is really bad compared to my ancient HP140T > spectrum analyzer with about 60dB of dynamic range. However, I would > not expect much more from such a unit. What this means is that there > will need to be some form of attenuator to deal with close in > sniffing, and possibly an adjustable gain amplifier for long range > work. > > I can just barely see my neighbors client radio at about 200ft with a > 2dBi antenna and a tangle of wet trees in between. I'm sure that with > an external antenna on the wi-spy, it would be detectable. > > I had my neighbor across the street (about 50ft) fire up their Uniden > something 2.4GHz cordless phone. I could see it, but just barely. > Again, more antenna gain would be helpful. > > 4. The software appears to be stable and quite useful. Whomever > wrote it apparently has used commercial spectrum analyzers. I had > some problems restarting the application after hibernation, but a > reboot solved that. I can run my Netgear WG511v2 PCMCIA card at the > same time. It makes for an interesting display, especially when the > card is scanning for access points. > > 5. I won't post any AVI recording files until I get a reproducible > setup and possibly butcher the unit with a better antenna. The ones > on the web site should be sufficient for now. > | http://recordings.metageek.net/index.php > > 6. The display is either by channel number or by frequency. It will > display all 14 UK channels, but when set to frequency, it reverts to > the 11 US channels (2400 to 2483.5). > > 7. I couldn't resist taking it apart and analyzing the hardware. It's > actually a DSSS wireless mouse receiver. The radio module is made by > Unigen: > | http://www.unigen.com/product05/W_JUNO/juno_probrief.cfm?part_number=UGQUBE1US > I had to apply for permission to download their secret data sheet. > Maybe later. > > Photos at: > | http://802.11junk.com/jeffl/pics/wireless/Wi-Spy/index.html > The square thing in the picture is a push button, usually used to > synchronize a wireless mouse with a USB adapter. The RF chips is a > Cypress Semi CYWUSB6934-48LFXC: > | http://www.cypress.com/portal/server.pt?space=CommunityPage&control=SetCommunity&CommunityID=209&PageID=259&fid=65&rpn=CYWUSB6934 > > The antenna is the wiggly affair on the right of: > | http://802.11junk.com/jeffl/pics/wireless/Wi-Spy/slides/Wi-Spy-01.html > It appears that I can easily attach a small coax pigtail for an > external antenna. Of course, the usual coffee can or dish reflector > can also be used. Some notes on the antenna design: > | http://www.cypress.com/portal/server.pt/gateway/PTARGS_0_2_1289_209_0_43/http;/sjapp20;7001/publishedcontent/publish/design_resources/application_notes/contents/wirelessusb_tm__antenna_design_layout_guidelines___an5032_9.pdf > > Bottom line is that it works and seems to work well enough. It will > need some modifications to attach an external antenna in order to make > it suitable for interference detection and location. It may take a > while for me to use it in the field (it's raining). However, the fact > that it can easily detect my leaky microwave oven and 2.4Ghz cordless > phone means that it is sure to be useful. > Thanks for the update. Noticed this is in their forum ,so will watch with interest. http://www.metageek.net/forum/viewtopic.php?t=13&sid=f160f25036a0e6ad8ba1d780e30a0d95 Spastic, I like this idea! Currently the average trace shows the average over all time or since the last time history was cleared. Your idea to scale the average in relation to the noisiest channel is good; another idea we have played with is just average the past 1-2 minutes of traffic. We will do further investigations into making the average trace more useful and will post a development build of version 1.1 sometime next week.
From: William P.N. Smith on 2 Jan 2006 10:01 Jeff Liebermann <jeffl(a)comix.santa-cruz.ca.us> wrote: >I've been playing with a Wi-Spy Spectrum Analyzer for a few hours. > http://www.metageek.net Thanks, Jeff, gotta get one on order!
From: Moe Trin on 2 Jan 2006 20:14
On Sun, 01 Jan 2006, in the Usenet newsgroup alt.internet.wireless, in article <eibhr1lhk49e1qlq8ha2lam2ur9r2m8ita(a)4ax.com>, Jeff Liebermann wrote: >$99 plus shipping. >3. Dynamic range sucks but that's understandable. The noise floor is >about -60dBm while the SA saturates at about -32dBm. Either that's a pretty wide bandwidth, or it's awfully noisy. Saturating at -32 sounds as if it's got something active in front of what ever is saturating. However, -32 out of a 3 dBi antenna isn't especially a weak signal in space. >That's 28dB of dynamic range which is really bad I'll say >compared to my ancient HP140T spectrum analyzer with about 60dB of >dynamic range. But then, a hundred bucks isn't going to pay for the power cord on that HP, and depending on the plug-in, the HP has a heck of a lot more scan width. Back when Marconi was still playing with spark gaps or something, I think we paid US$12k for the 8555 (10 KHz - 12.4 GHz). >However, I would not expect much more from such a unit. What this means >is that there will need to be some form of attenuator to deal with close >in sniffing, and possibly an adjustable gain amplifier for long range >work. Mini Circuits Lab used to make a nice low noise preamp - problem is the onezy cost is probably more than you paid for the Wi-Spy. >It may take a while for me to use it in the field (it's raining). As long as the Mighty San Lorenzo is staying within it's banks (you guys are hogging all the precip - we got a 10% chance tonight, which would be the first rain since early November). Old guy |