It's crazy that everyone is using 2.4Ghz for Wi-Fi. My flat is swamped with 2.4Ghz WiFi all conflicting with each other for the 3 non-overlapping channels and the much larger 5Ghz range is completely unused.
Why 2.4GHz? Chasing wireless history
41–50 of 57 posts
Re: Why 2.4GHz? Chasing wireless history
#42I don't know the answer to why the 2.4GHz ISM band is at 2.4GHz, but I do know the answer as to why the 2.4GHz band was chosen over others. (I also know why the 61.5 GHZ ISM bad was chosen to be 61.5GHz.) The choice of the 2.4GHz band needs to be seen in the context of 1995, when the first WLAN prototypes were built. The lower limit was set by the desire to have the smallest antennas possible, to allow WLAN equipped…
Your post is full of errors. CMOS radio didn't exist in 1995. 802.11a didn't come out 'after' 802.11b. 802.11a and 802.11b were ratified on the SAME DAY. 802.11g is a bit more than "802.11a in 2.4GHz".
after a little googling i can find references to papers pblished in 1994 and 1995 that refer to GHz CMOS components (eg A. Rofougaran et al., A 1 GHz CMOS RF
Front-end IC with Wide Dynamic Range,
ESSCIR, 1995, pp. 250-253; J. Carols and M. S. J. Steyaert, A 1.5 GHz Highly
Linear CMOS Down Conversion Mixer, IEEE
Journal of Solid-State Circuits, Vol. 30, 1995,
pp. 736-742.)
i know nothing about this, so perhaps they are irrelevant, but on face value it seems like a 2.5GHz system could have existed in labs at that date, or at least was clearly going to be possible.
Re: Why 2.4GHz? Chasing wireless history
#43[deleted]
Re: Why 2.4GHz? Chasing wireless history
#44We had 2.4 GHz systems working in 1992. They were crude frequency hoppers, but they worked and were designed to take advantage of the FCC rules for the unlicensed ISM bands.
The first WLANs that were similar to what we have today with APs and mobile clients were in the late 80s
Re: Why 2.4GHz? Chasing wireless history
#45Earlier quoted context omitted.
I'm looking at this from the point of view of the technology, rather than the standards, as that's where I was involved. From a technology point of view, 802.11b (particularly its 1 and 2Mbps modes) was developed before 802.11a, and so is "older". I know this, because I had the design for the world's first 802.11a modem on my computer's screen, and one of the professors had earlier bought an instance of a DSSS WLAN (…
802.11b was CCK modulation (and to a lessor extent PBCC, but that didn't take-off). DSSS wasn't 802.11b, it was 802.11 (or half of it, the other PHY at that point was FHSS). 802.11b's 1Mbps and 2Mbps modes were DSSS, and pre-existed 802.11b. These (and the FHSS PHY) were all part of the 1997 standard. 802.11b and 802.11a came along in September of 1999. Who is 'we'? Because you don't seem to know what you're talking…
Is there any need to be so uncivilly acerbic?
Re: Why 2.4GHz? Chasing wireless history
#46Good luck with your search! Out of interest, have you tried approaching the University to see if they have funds available to help you out? That would be my first port of call - $500USD isn't much to them.
It certainly crossed my mind, but given financial constraints at the moment I didn't think they would jump on the idea. Also, this is a complete side topic for my real research, so I shouldn't even be doing it. It's tweaked some interest now though so they certainly might be more amenable, if nothing for the good PR.
They're making a big song and dance about being poor, but Universities still have tons of cash sloshing about :)
Fair point though if it's not something explicitly connected with your research - but good thinking about the publicity aspect of it :)
Best of luck with it all - please forgive my non-donation, I'm a student too and, as you know, it's feast or famine and this is the back end of a semester ;)
Re: Why 2.4GHz? Chasing wireless history
#47It's crazy that everyone is using 2.4Ghz for Wi-Fi. My flat is swamped with 2.4Ghz WiFi all conflicting with each other for the 3 non-overlapping channels and the much larger 5Ghz range is completely unused.
Really? That sort of thing actually is part of my research. Could you possibly forward a screenshot of what it looks like? Netstumbler or the OS's wifi control panel. If you could also describe the urban environment (apartments or houses, how many occupants, etc) that would be amazing. Thank you!
Re: Why 2.4GHz? Chasing wireless history
#48It's crazy that everyone is using 2.4Ghz for Wi-Fi. My flat is swamped with 2.4Ghz WiFi all conflicting with each other for the 3 non-overlapping channels and the much larger 5Ghz range is completely unused.
Really? That sort of thing actually is part of my research. Could you possibly forward a screenshot of what it looks like? Netstumbler or the OS's wifi control panel. If you could also describe the urban environment (apartments or houses, how many occupants, etc) that would be amazing. Thank you!
Ok, email me (it's in my profile) and I'll email you them back
Re: Why 2.4GHz? Chasing wireless history
#49Earlier quoted context omitted.
Your post is full of errors. CMOS radio didn't exist in 1995. 802.11a didn't come out 'after' 802.11b. 802.11a and 802.11b were ratified on the SAME DAY. 802.11g is a bit more than "802.11a in 2.4GHz".
after a little googling i can find references to papers pblished in 1994 and 1995 that refer to GHz CMOS components (eg A. Rofougaran et al., A 1 GHz CMOS RF Front-end IC with Wide Dynamic Range, ESSCIR, 1995, pp. 250-253; J. Carols and M. S. J. Steyaert, A 1.5 GHz Highly Linear CMOS Down Conversion Mixer, IEEE Journal of Solid-State Circuits, Vol. 30, 1995, pp. 736-742.) i know nothing about this, so perhaps they ar…
many people were chasing the dream of CMOS radio in the mid-90s.
You could even make it work in the lab, but holding a design in production wasn't possible then.
Re: Why 2.4GHz? Chasing wireless history
#50It's crazy that everyone is using 2.4Ghz for Wi-Fi. My flat is swamped with 2.4Ghz WiFi all conflicting with each other for the 3 non-overlapping channels and the much larger 5Ghz range is completely unused.
Really? That sort of thing actually is part of my research. Could you possibly forward a screenshot of what it looks like? Netstumbler or the OS's wifi control panel. If you could also describe the urban environment (apartments or houses, how many occupants, etc) that would be amazing. Thank you!
Lots of networks is pretty common everywhere I look. In commercial buildings with lots of tenants it is even worse. I live in suburbia (detached houses) and can see between 5 and 10 networks depending on which corner of the house I am in. Only my own AP was on 5GHz, but discovered someone else has finally started using that range too. It also looks like several of my neighbours turn their wifi off when they are not at home!
If you want to collect this kind of data, then an easy way is to ask Android users to run "Wifi Analyzer" and use the Share menu to send you the results. It is a glob of XML but includes all the necessary details.