 
Matt
Take me down to the paradise city
Premium
join:2003-07-20
Jamestown, NC | Actually Standard 802.11b access points use 100 to 200 milliwatts, not 1 watt.
So that is like, .0001 or .0002 watts right?
It's 1 watt EIRP that they are limited to. | |
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BlaZeR2
join:2001-05-28
Taylor, MI | Re: Actually Actually, I believe 100 or 200 milliwatts, is more like .1 watt or .2 watts. Since 1 milliwatt is .001. so 100 x .001 = .1
Someone please correct me if I am wrong. | |
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Matt
Take me down to the paradise city
Premium
join:2003-07-20
Jamestown, NC
 ·North State Commun..
| Re: Actually said by BlaZeR2  :Actually, I believe 100 or 200 milliwatts, is more like .1 watt or .2 watts. Since 1 milliwatt is .001. so 100 x .001 = .1 Someone please correct me if I am wrong. You are correct, Google to the rescue!
»www.google.com/search?hl=en&lr=&···in+watts | |
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Maarvin
Premium
join:2005-04-11
Denver, CO | I believe that they want to go to .5 milliwatt. This is a ridiculously low power output. Something doesn't seem right here. Perhaps these power ratings are all typo's. | |
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hurleyp
join:2000-06-20
Ottawa, ON | Re: Actually I agree. There seems to be something fishy about a power output claim that is so small that it sounds more theoretical than measurable.
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"I reject your reality and substitute my own." | |
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| | nasadude
join:2001-10-05
Rockville, MD
 ·Comcast
| said by Maarvin :I believe that they want to go to .5 milliwatt. This is a ridiculously low power output. Something doesn't seem right here. Perhaps these power ratings are all typo's. the article says for long range, 50mW = .05W
for 10m distance, 3nW = .000000003
still, an extremely low power for such coverage | |
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| vernalex
Premium
join:2000-10-19
Manchester, CT | Also...
Unlicensed people are restricted to 100mW or below. Most SOHO routers / access points are usually about 45 or abouts. | |
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Matt
Take me down to the paradise city
Premium
join:2003-07-20
Jamestown, NC
·North State Commun..
| Re: Actually said by vernalex :Also... Unlicensed people are restricted to 100mW or below. Most SOHO routers / access points are usually about 45 or abouts. Unlicensed people are restricted to 1 watt EIRP.
It doesn't matter what provides that 1 watt. 
»www.wi-fiplanet.com/tutorials/ar···/1428941 | |
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DaDogs
Semper Vigilantis
Premium
join:2004-02-28
Deltaville, VA
1 edit | Re: Actually said by Matt :said by vernalex :Also... Unlicensed people are restricted to 100mW or below. Most SOHO routers / access points are usually about 45 or abouts. Unlicensed people are restricted to 1 watt EIRP. It doesn't matter what provides that 1 watt. » www.wi-fiplanet.com/tutorials/ar···/1428941 Actually it does matter how that EIRP is generated. From the article you cite:
A typical indoor WLAN consists of enough access points to cover the facility to enable wireless mobility for users. Radio NICs in user devices and access points generally have omni-directional antennas that propagate RF energy in most directions, which maximizes connectivity for mobile applications. When using omni-directional antennas having less than 6 dB gain in this scenario, the FCC rules require EIRP to be 1 watt (1,000 milliwatts) or less.
In most cases, you'll be within regulations using omni-directional antennas supplied by the vendor of your radio NICs and access points. For example, you can set the transmit power in an 802.11b access point or client to its highest level (generally 100 milliwatts) and use a typical 3 dB omni-directional antenna. This combination results in only 200 milliwatts EIRP, which is well within FCC regulations.
FCC loosens up
The FCC eases EIRP limitations for fixed, point-to-point systems that use higher gain directive antennas. If the antenna gain is at least 6 dBi, the FCC allows operation up to 4 watts EIRP. This is 1 watt (the earlier limitation) plus 6 dB of gain.
IFF you get a 9 dBi omni directional antenna and attach it to a 27 dBm radiator (.5) watts. You can legally radiate at 36 dB EIR four (4) watts.
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How can I improve my WiFi signal? | |
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91439306
15,000 Watts of Bass Power
join:2002-10-16
New Milford, CT
| Re: Actually said by DaDogs :said by Matt :IFF you get a 9 dBi omni directional antenna and attach it to a 27 dBm radiator (.5) watts. You can legally radiate at 36 dB EIR four (4) watts. There is no such thing as a "9 dBi omnidirectional antenna" by the very definition. Omnidirectional IS an isotropic radiator, which, by definition is 0dBi. The means of increasing gain is by restricting radiation to a particular plane or direction. Thus the term, dBi, being the gain of the subject antenna, referenced to an isotropic (omnidirectional) radiator. Other references can be dBd (referenced to a halfwave dipole antenna, which has 3dBi gain (referenced to an isotropic radiator. Thus, isotropic have no gain, or unity gain, because they radiate in all directions. In practice, there is no man made perfect isotropic radiator because of nearby influences distorting the pattern to make it somewhat directional. So we talk about antenna gain being referenced to something, either the dipole or the hypothetical isotropic radiator. Gain is achieved by focusing the energy in a particular plane or direction, thus an omnidirectional can, by definition, have no gain. --
Take care,
Mark & Mary Ann Weiss
Hear my Kurzweil Creations at: »www.dv-clips.com/theater.htm
'»www.mwcomms.com/auctions.htm
'»www.mwcomms.com
'»www.adventuresinanimemusic.com
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DaDogs
Semper Vigilantis
Premium
join:2004-02-28
Deltaville, VA
1 edit | Re: Actually said by 91439306 :said by DaDogs :IFF you get a 9 dBi omni directional antenna and attach it to a 27 dBm radiator (.5) watts. You can legally radiate at 36 dB EIR four (4) watts. There is no such thing as a "9 dBi omnidirectional antenna" by the very definition. Omnidirectional IS an isotropic radiator, which, by definition is 0dBi. The "popular" usage of the term "omni-directional antenna" is an antenna which has uniform gain in the plane of the earth for 360 degrees around.
You may want to delude yourself into believing that is not what people understand it to mean but I will refer you to the vast compendium of literature upon the subject. Including the very FCC document we are referencing.
said by 91439306 :The means of increasing gain is by restricting radiation to a particular plane or direction. Thus the term, dBi, being the gain of the subject antenna, referenced to an isotropic (omnidirectional) radiator. Perhaps we should correct the reference above so that it agrees with the FCC's use of the term in their documents as well as the use of the term in the community. Google for "omnidirectional antenna" and show me the Isotropic radiator you find which is equated to the omnidirectional antennas you find for sale...
This is crap. We don't need to redefine the language of the industry... Gawd...
said by 91439306 :Other references can be dBd (referenced to a halfwave dipole antenna, which has 3dBi gain (referenced to an isotropic radiator. I'm sorry, but that is incorrect. In the industry we currently consider a dipole to have approximately 2.17 dBi gain. My computer models of dipoles generally show about that much gain, by the way.
said by 91439306 :Thus, isotropic have no gain, or unity gain, because they radiate in all directions. Yes, but omnidirectional antennas, as the term is used in the wireless industry, and by the FCC in its literature, may indeed exhibit gain over an isotropic radiator.
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Thanks for the basics on antennas. May I refer you to one of my web sites.
»www.freeantennas.com
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91439306
15,000 Watts of Bass Power
join:2002-10-16
New Milford, CT
| Re: Actually Popular in what era? Back in the 50s and 60s (and even into the 70s) when I designed antennas for VHF broadcast applications, the common term for omnidirectional was 'isotropic radiator'. The closest antenna to being an isotropic radiator in today's market are the ERI 'rototiller' circularly-polarized FM broadcast antennas so commonly in use. It isn't until you stack them and control the phase of the input power to each bay that directional patterns along the horizon come into play. There are quite a few FMs in the class A FCC designation that are close to isotropic in radiation pattern and are termed 'omnidirectional'.
Now it is true that you can have a series of dipoles stacked vertically to provide a doughnut-shaped pattern, and by increading the number of vertical radiators, one can compress the vertical plane of radiation to increase reach along the horizon.
Which FCC document are you referencing that talks about the 9dBi radiator? It seems that many in the FCC in recent years have lost touch with the proper definitions for technical terms, and I have noticed a propensity toward these mistakes since 1996 or so.
It seems the industry has redefined the language of science and engineering. Most likely the marketing branches of various manufacturers.
Your model of the 2.17dBi dipole may take into account certain factors like conductivity of ground, capacitive coupling and other real world factors that affect actual gain, vs. the theoretical mathematical model of a dipole that I, and the industry for the past 60 years have used.
The dipole halves the radiation pattern, therefore it DOUBLES the power in the remaining radiation pattern. Double power is a 3dB increase.
Again, it appears that the recent wireless industry and the changes to terminology made by marketing folks have caused you some confusion. I still use the terms that come from the original science of radio and antenna design. Even going back to my 1961 edition of the Radio Ameteur's Handbook, a fairly recent document in the course of my career, isotropic is treated like an omnidirectional radiator.
--
Take care,
Mark & Mary Ann Weiss
Hear my Kurzweil Creations at: »www.dv-clips.com/theater.htm
'»www.mwcomms.com/auctions.htm
'»www.mwcomms.com
'»www.adventuresinanimemusic.com
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DaDogs
Semper Vigilantis
Premium
join:2004-02-28
Deltaville, VA
| Re: Actually said by 91439306 :Popular in what era? Back in the 50s and 60s (and even into the 70s) when I designed antennas for VHF broadcast applications, the common term for omnidirectional was 'isotropic radiator'. The closest antenna to being an isotropic radiator in today's market are the ERI 'rototiller' circularly-polarized FM broadcast antennas so commonly in use. Google is your friend.
»www.google.com/search?hl=en&lr=l···+Antenna
Mind you, I am only fifty three years old and I am not an EE, I am a mere Computer Scientist so I may have to defer to your somewhat "dated" meanings for terms.
said by 91439306 :... It seems the industry has redefined the language of science and engineering. Most likely the marketing branches of various manufacturers. We agree upon that, at the least.
said by 91439306 :Your model of the 2.17dBi dipole may take into account certain factors like conductivity of ground, capacitive coupling and other real world factors that affect actual gain, vs. the theoretical mathematical model of a dipole that I, and the industry for the past 60 years have used. Again Google is your friend.
»www.google.com/search?hl=en&lr=l···fine:dBd
It seems that 2.17 dBi is a bit more than the industry now accepts. My bad.
said by 91439306 :The dipole halves the radiation pattern, therefore it DOUBLES the power in the remaining radiation pattern. Double power is a 3dB increase. Understood but a dipole does not really halve the area of the pattern. It is convienent to use 3 dBi as the gain of a dipole as it is easy to use in computations, but the the gain of a "resonant half-wave dipole" in the real world (and as used by the industry today) is somewhat less than 2.5 dBi.
said by 91439306 :Again, it appears that the recent wireless industry and the changes to terminology made by marketing folks have caused you some confusion. Not at all. My training in antenna theory comes from my training in the service cryptologic agencies back in the early 70's and even at that time I was told a dipole had 2.2 dBi gain.
said by 91439306 : I still use the terms that come from the original science of radio and antenna design. Even going back to my 1961 edition of the Radio Ameteur's Handbook, a fairly recent document in the course of my career, isotropic is treated like an omnidirectional radiator. Time to get the newer literature. I have some books here which are somewhat dated as well. I have, for example, the original "antenna handbook" by Ken "Judge" Glanzer, K7GCO, "Volume 1, Theory and Practice, 1966" of which I am quite fond because of the things I learned about terminated long wire antennas and used in the field of applied Electronic Warfare . Mind you the oldest copy of the ARRL Antenna Book I have is dated 1974 and it weighs about one fifth of the 19th Edition ARRL Antenna Book I have dated 2000. There are the other mandatory readings I have handy, "Microwave Experimenters Handbook", "ARRL Handbook for Amateurs" but you get the idea.
Here is another great resource if you have not already found it.
»www.w1ghz.org/antbook/preface.htm
Whatever....
dah dah di di dit
di di di dah dah
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How can I improve my WiFi signal? | |
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RayW
Premium
join:2001-09-01
Layton, UT
clubs:
·XMission
| .5 milliwatt? Is that at one frequency or spread out over a spectrum? MY 1 mw 916.5 MHz weather station transmitter has a hard time getting 100 feet through the walls. Wonder what type of beam forming they are using? 1 degree beams?
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I am not lost, I find myself every time. | |
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phuntism
join:2003-08-01
Manhattan Beach, CA
| The lower radiation the better I guess I know it's not a big deal, and that 1 watt is extremely low compared to an 1100 watt microwave oven, but considering many people these days spend most of their lives within range of one or many access points, I'll welcome less radiation. Now if they could just do the same for cell phones | |
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| lawrence171
Evilly Yours - Evilness
join:2001-12-24
Canada
| Re: The lower radiation the better I guess said by phuntism :I know it's not a big deal, and that 1 watt is extremely low compared to an 1100 watt microwave oven, but considering many people these days spend most of their lives within range of one or many access points, I'll welcome less radiation. Now if they could just do the same for cell phones CDMA technologies. Get urself a nice Verizon or Sprint wireless service.
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What I used to be I no longer am... God, why can't you freeze time for my sake? | |
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| | itguy05
join:2005-06-17
Camp Hill, PA | Re: The lower radiation the better I guess quote:
CDMA technologies. Get urself a nice Verizon or Sprint wireless service.
Why? They transmit ALL THE TIME vs GSM which transmits in bursts. | |
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Vig
Thread-safe since 1997
Premium
join:2004-03-23
San Diego, CA
| Re: The lower radiation the better I guess CDMA devices use far lower power than GSM. The total power output is a good deal lower. If you're really paranoid about evil radiation, you'd be better off using CDMA.
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Visit the land of the never-setting sun | |
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DaDogs
Semper Vigilantis
Premium
join:2004-02-28
Deltaville, VA
| Re: The lower radiation the better I guess said by Vig :CDMA devices use far lower power than GSM. The total power output is a good deal lower. If you're really paranoid about evil radiation, you'd be better off using CDMA. Actually one would have to compute the power absorbed over time to know that with any certainty. If one transmits at 1 mw constantly and the other transmits at 60 mw for one second every minute. They would be equal assuming the exposure distance were equal.
Now if one transmitted at 1 mw 24x7x365 and the other transmitted at 60 mw twenty minutes per day, every day. The first would expose you to 86,400 mw/seconds per day while the second would expose you to 76,800 mw/seconds per day.
Anyway you get the idea.
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How can I improve my WiFi signal? | |
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| | | | | fgoldstein
join:2003-01-21
Newton Highlands, MA
·RCN CABLE
| Re: The lower radiation the better I guess He's right about CDMA using less power; that's one reason I use CDMA.
One reason is simply that CDMA adjusts its power by 1 dB every millisecond, in a closed-loop power control circuit, so its SNR is always around 1-2 dB above what's needed.
Another reason is that CDMA spreads the signal over >1 MHz, while Rayleigh fading creates notches much narrower than that, about the width of GSM IIRC. So a mobile CDMA unit will not experience nearly as much Rayleigh fading (it gets maybe 1 dB) as a narrowband radio. GSM suffers Rayleigh fading, so it has to turn up the power by maybe 10 dB to overcome it. A stationary GSM unit might be able to run CDMA-like power though; I don't know how tight it runs its power control loop. | |
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JamesPC
join:2005-10-12
Orange, CA | More than a Mile? I currently use Wifi at my house and i get about .5 mile away. Does xmax technology expand the wireless range? | |
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| clickie
join:2005-05-22
Monroe, MI
| Re: It's using You are hereby notified that you are wrong and corrected.
VHF contains numerous services including public service, GMRS, the reviled ham radio band, broadcast, remote telemetry and tons other.
UHF is full of land mobile services, as well as the above. It is very very busy.
See for yourself here:
»www.ntia.doc.gov/osmhome/allochrt.pdf | |
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David
No,there is another.
Premium,VIP
join:2002-05-30
Granite City, IL
clubs: | Re: It's using Thank you, I kept thinking it was a somewhat open frequency range..
I had a feeling I was wrong.
Thanks.. | |
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FLECOM
Bay Networks Freak
Premium
join:2003-03-03
Miami, FL | GMRS/FRS is UHF
MURS is vhf
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BellSouth sucks | |
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| | | clickie
join:2005-05-22
Monroe, MI | Re: It's using I can never keep any of that stuff straight. | |
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FLECOM
Bay Networks Freak
Premium
join:2003-03-03
Miami, FL
1 edit | actually VHF/UHF is pretty congested in most areas, 900mhz is not VHF btw...
800~900 is extremely congested with commercial and public safety systems, 800 especially (thanks nextel!)... uhf is mostly land mobile radio systems like taxi companies and lots of public safety also... things like FRS/GMRS are also in UHF...
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BellSouth sucks | |
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clickie
join:2005-05-22
Monroe, MI
| 1999 Called... ...and it wants its outrageous and bogus claims with its associated white elephants back.
Here's the rub; in order to have that kind of bandwidth at such a low power, the instantaneous power at any given point in the modulated spectrum will require incredibly sensitive receivers. Those are not built with common parts. Furthermore, to be that wide and that sensitive makes them very prone to interference; either fundamental or mixing products. Solving that also isn't very simple nor very cheap.
It might work at ranges of a mile out in a cornfield in Nebraska. Definetly not going to happen in New York city. | |
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FLECOM
Bay Networks Freak
Premium
join:2003-03-03
Miami, FL
| Re: 1999 Called... i agree, they are doing .0005 watts on vhf... i key my 6w vhf handheld and blast everyone offline for miles? 
i dunno it just dosent really add up... i dont doubt you can go miles with .0005w of VHF, providing you have very directional/parabolic antennas or something...
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pokesph
It Is Almost Fast
Premium
join:2001-06-25
Sacramento, CA
clubs: | Re: 1999 Called... or I key my 150 watt 150 Mhz mobile and bam the whole city's down..
this really sounds too fishy for my tastes.. | |
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FLECOM
Bay Networks Freak
Premium
join:2003-03-03
Miami, FL | Re: 1999 Called... you got me beat, my mobile is only 110w 
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Heterman
Premium
join:2004-02-28
Fayetteville, AR
| said by FLECOM :i agree, they are doing .0005 watts on vhf... i key my 6w vhf handheld and blast everyone offline for miles? i dunno it just dosent really add up... i dont doubt you can go miles with .0005w of VHF, providing you have very directional/parabolic antennas or something... I agree. I don't think you can get any type of range out of an omnidirectional antenna with that type of power. JMO | |
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KAD Imaging
Just Shoot It
Premium
join:2002-09-21
Hialeah, FL
·AT&T Southeast
| Re: 1.21 "jigowatts" said by Jeffrey :I'm anxiously awaiting reports that someone successfully built and tested the flux capacitator. LMAO!! "MARTY!! THE STORM IS COMING!!!"
 :D:D:D:D | |
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DataDoc
My avatar looks like me, if I was 2D.
Premium
join:2000-05-14
Greenville, NC
·Suddenlink
| said by Jeffrey :I'm anxiously awaiting reports that someone successfully built and tested the flux capacitor. Me,too. Then I can complete my Iterociter.
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NotATroll
@207.195.x.x | The technology is doomed... as soon as those whiney hams start complaining about interference with the spectrum they think they own.
Too bad though, sounds like an affordable broadband solution for rural areas. | |
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See 7 replies to this post |
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fgoldstein
join:2003-01-21
Newton Highlands, MA
·RCN CABLE
| Two words... Madison Priest. Look him up.
Shannon's laws cannot be violated; they are about math, not human technology. You can theoretically run any bandwidth with any power, but you're constrained by the signal-to-noise ratio, which constrains range. Very low power has a short range or a narrow bandwidth. You can do a lot better than WiFi, which is inefficient, but there's no magic that lets a microwatt carry high speeds for long distances. | |
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justncredible
@rr.com | Re: Two words... they run it under the noise floor and tune the receiver to pick it out of the noise. Pretty simple. I think it could be well used for BPL, and the entire spectrum could then be used with this. It violates no laws. | |
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zerobias
@wdiv.com
| Re: Two words... Explain to me how you differentiate signal from the noise if the noise is of greater energy than the desired signal?
Yes, you can tell it's there. But you're not going to get a megabit of data through it.
If it were only that simple... | |
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justncredible
@rr.com
| Re: Two words... It is tuned to that signal, it will not even "hear" the noise. Also it is not random. The receiver will ignore signals of higher strength and pick up only the smaller ones then separate them out. It will take a processor and could not have been done 20 years ago. Anyway we will be seeing it this month or so the article said. Go stick yer head in the sand if ya want. Me, I think in 5 years this will be everywhere, a uncontrollable wi fi network from coast to coast. Done from peoples cable connections. | |
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zerobias
@wdiv.com
| Re: Two words... Incorrect. The receiver hears everything, including noise. It's up to the demodulator and subsequent stages to ignore noise and stronger signals.
I'm not sticking my head into the sand, I'm trying to figure out how it works. So far, all I've been told is that it magically works by transmitting scads of data using miniscule amounts of power, with signals deep into the mud and overcomes any interference like it isn't there. Oh, and it does it cheaply with few parts.
Cheap, wideband pre-amps of the 60 dB variety with any meaningful stability are not exactly cheap. And that's not counting the rest of the parts behind it. | |
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| | fgoldstein
join:2003-01-21
Newton Highlands, MA
·RCN CABLE
| By definition, if it's really noise, then it impacts the Shannon SNR, and thus the receiver can't "pick it out of the noise". Shannon does not have a "noise floor"; rather, as the signal gets weaker, the receivable bit rate declines. It does not hit zero.
This does no good for BPL, which is simply a source of broadband noise (technically QRM interference, not QRN random noise, but in practical terms the same thing) across the HF spectrum. BPL's problem isn't receiving, it's leaking. Power lines are antennas, not RF transmission lines. | |
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rfblast
| Simple method Actually this new modulation technique has been talked about before. Its actually pretty simple. Think harmonics. Now add multiple receiver's. One for the fundamental, two for each side of the third order, two for the 5th etc etc. Now take the outputs of the receiver into a comparator. Not only do you get a very accurate receiver and recreation of the original wave form, but it also becomes error corrected and you get another plus; you can lower the power level because your comparing multiples signals. Think op amps........want more bandwidth, just increase power, which creates higher level harmonics and add more receiver's. | |
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digiblur
Got Sipura?
Premium
join:2002-06-03
Louisiana
| Comparing Apples and Oranges So what that it takes 2000 times less power than a 802.11 access point? VHF is a long ways away in the spectrum from 2.4ghz. Generally speaking the lower you go the less power you need to "get out". For example look at some of the digital OTA TV signals. You'll see a tower pushing 30kw at 210mhz then you'll see a tower pushing 1000kw at 662mhz. Compare the size of their coverage area and they are almost identical with the 30kw signal being a little bigger.
--
FWD#64466(6PM-11PM GMT-5)
»[Sipura] Make your Sipura Speak! - GetSipura Guide
And now for the PAP2-NA and unlocked PAP2's. | |
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| RayW
Premium
join:2001-09-01
Layton, UT
clubs:
·XMission
| Re: Comparing Apples and Oranges said by digiblur :So what that it takes 2000 times less power than a 802.11 access point? VHF is a long ways away in the spectrum from 2.4ghz. Generally speaking the lower you go the less power you need to "get out". For example look at some of the digital OTA TV signals. You'll see a tower pushing 30kw at 210mhz then you'll see a tower pushing 1000kw at 662mhz. Compare the size of their coverage area and they are almost identical with the 30kw signal being a little bigger. Line of sight signals at those frequencies, of course they would be similar coverage.
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I am not lost, I find myself every time. | |
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digiblur
Got Sipura?
Premium
join:2002-06-03
Louisiana
| Re: Comparing Apples and Oranges said by RayW :said by digiblur :So what that it takes 2000 times less power than a 802.11 access point? VHF is a long ways away in the spectrum from 2.4ghz. Generally speaking the lower you go the less power you need to "get out". For example look at some of the digital OTA TV signals. You'll see a tower pushing 30kw at 210mhz then you'll see a tower pushing 1000kw at 662mhz. Compare the size of their coverage area and they are almost identical with the 30kw signal being a little bigger. Line of sight signals at those frequencies, of course they would be similar coverage. Huh?
--
FWD#64466(6PM-11PM GMT-5)
»[Sipura] Make your Sipura Speak! - GetSipura Guide
And now for the PAP2-NA and unlocked PAP2's. | |
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| | | RayW
Premium
join:2001-09-01
Layton, UT
clubs:
·XMission
| Re: Comparing Apples and Oranges said by digiblur :said by RayW :said by digiblur :So what that it takes 2000 times less power than a 802.11 access point? VHF is a long ways away in the spectrum from 2.4ghz. Generally speaking the lower you go the less power you need to "get out". For example look at some of the digital OTA TV signals. You'll see a tower pushing 30kw at 210mhz then you'll see a tower pushing 1000kw at 662mhz. Compare the size of their coverage area and they are almost identical with the 30kw signal being a little bigger. Line of sight signals at those frequencies, of course they would be similar coverage. Huh? The higher in frequency you get above 30 MHz, the less the tendency of signals to bounce off of the ionosphere or curve around the earth. At VHF and up, in most cases if you can see the antenna you can receive the signal (thus the term line of sight). While there is some bending, VHF and UHF are very similar in most cases as far as clear air propagation.
There are other reasons for more power than range in the cases you stated.
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I am not lost, I find myself every time. | |
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digiblur
Got Sipura?
Premium
join:2002-06-03
Louisiana | Re: Comparing Apples and Oranges LOL... you totally missed my point. | |
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| | | | | RayW
Premium
join:2001-09-01
Layton, UT
clubs:
·XMission
| Re: Comparing Apples and Oranges said by digiblur :LOL... you totally missed my point. Obviously I do miss your point since I read it as an engineer, a literal posting. If you were being sarcastic, I missed it.
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I am not lost, I find myself every time. | |
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jdir
join:2001-05-04
Santa Clara, CA
| xMAX After reading the article about xMax, one minor items that caught my eye - the transmitter antenna is on top of a 260M tall tower - that's like above the tree line. What I like to see test is the transmitter is mount on a 16 feet tower and has building arounds for reflections and other nifty radio "problems" | |
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.0005 Watt Wireless
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Bandwidth, Security and practical use status