just to tell you that I have 2.4 ghz kinks that run over 4 km on normal wifi power level. and I have one that is over 34 km on just 3dm more then normal wifi power.. And we have humidity level around here that are around 70% at a minimum in the sommer/ winter and way more in the spring and automn. your explanation of the absorbtion of a 2.4 ghz signal need to be revisited.
Sent from my iPad > On Jan 1, 2016, at 4:38 PM, Chuck McManis <chuck.mcma...@gmail.com> wrote: > > Srini, you have remarked about this several times over the last year and > while appreciate your enthusiasm I think this comment: > > It seems , they don't understand about Radio and 2.4 GHz > > Might hit a bit closer to home. It would suffice it to say that *YOU* don't > understand about Radio and 2.4Ghz and that is why you don't see the obvious > way to answer your own questions, and why we cannot answer them. > > 2.4Ghz is absorbed by water, because the water molecule forms a small dipole > antenna of the correct length. That is why it is used in microwaves because > it heats the water and that hot water heats the rest of the food. It is also > why it is rarely used for long range communication, as the air has moisture > in it which absorbs the signal, so not only are you fighting the inverse > square law you're fighting atmospheric absorption. When it *is* used to send > a signal more than a mile it is done so with a highly directional antenna > pointing at another highly directional antenna on the receiving end. > > If you are seeing *any* sort of bump in the 2.4Ghz band, the source has to be > less than a mile away and probably less than 1000 meters (or 1km). So what > ever it is you're worried about, it is literally right next to you. Second > 2.4Ghz is *HIGHLY* directional, it doesn't bounce much and bounces get double > absorption so using any sort of directional antenna and a bit of geometry you > could exactly pin point any *SOURCE* of 2.4 ghz power. And in my experience > once you look at the thing sending out the RF energy you now exactly what it > is trying to do. > > So build one using a potato chip can (or buy) a directional WiFi antenna, > hook it up, and rotate it around until your mystery signal peaks. Note your > GPS coordinates and the angle with a good compass. Then drive 500 meters in > any direction and do that again, then 500 meters in a *different* direction > and do it a third time. (the protects against you accidentally picking a > direction that is in line with the transmitter). Now take a map, and put your > protractor on it, mark your tree measurement points and the angle. Draw lines > out from the point. They will cross at the point where the transmitter is, go > there. Look at the transmitter and what ever it is will be clear. If it is > moving then that would be another good clue for you. > > But here is the thing, you will never figure out what this is just by > observing a signal, you have to go look at it. > > --Chuck > > >> On Fri, Jan 1, 2016 at 12:23 AM, Srinivasan T <tsvs...@gmail.com> wrote: >> Hi There, >> >> >> >> I detected unknown RF at 2.4 GHz which is not Wi-Fi. >> >> This RF is not Wi-Fi, Bluetooth or Microwave, It has different FFT pattern, >> waterfall, and sound signature. >> >> This signal also deliver Wi-Fi packets to make people believe it is Wi-Fi >> packets. >> >> >> >> I use AirMagnet XT - 2.4 GHz and the software also detected unknown >> interference. >> >> Attached my analysis document. >> >> https://mega.nz/#!YwplVCCT!Acbe00paHk3dLJuf04B5zSBifSw0-bHz5IciiNLgQwY >> >> >> >> Please see following pages for quick understanding : >> >> 1. Page 18-19 : Conclusions >> >> 2. Page 43-46 : This page contains analysis of Radio >> Sound from 3 aspects : Sound Track, Sound Wave Form, >> >> Sound WaterFall pattern. We >> can see that huge difference between Wi-Fi 2.4 GHz sound and unknown Radio >> Signal >> >> 3. Page 47-51 : This external signal cause wifi >> fluctuations. Page 47 contains sample Wi-Fi signal from US which is really >> normal. >> >> Page 50, using AirMagnet >> XT ( 2.4 GHx spectrum analyzer ) we can see that the external interference >> cause nearly 10 channels >> >> affected. This is abnormal >> interference. >> >> 4. Page 52 : Relation of RF to human brain >> frequency >> >> 5. Page 61 : Video as reference, one of video : >> >> >> >> Unknown RF at 2.4 GHz reaction with human body with EEG >> >> http://sendvid.com/dofuepqn >> >> Details : This video shows the waterfall images. Each time >> we see set lines, the individual >> >> will feel the reaction to body which not able to show to any >> other people. Please see EEG >> >> window at right side at time 6.20 - 6.25 , 6.30-6.40, 6.50 - >> 6.55. The spike on EEG is >> >> trigger by external factor and the individual can feel it. >> >> ( other pages as >> supporting analysis ) >> >> >> >> I reported this issue to 3 RF spectrum managers : >> >> 1. iDA - Singapore >> >> 2. MCMC - Malaysia >> >> 3. Balmon - Indonesia >> >> >> >> It seems , they don't understand about Radio and 2.4 GHz >> >> >> >> If anyone could help with more data will be much appreciated or anything >> else. >> >> >> >> Regards >> >> >> >> Srinivasan T >> >> >> >> >> _______________________________________________ >> HackRF-dev mailing list >> HackRF-dev@greatscottgadgets.com >> https://pairlist9.pair.net/mailman/listinfo/hackrf-dev > > _______________________________________________ > HackRF-dev mailing list > HackRF-dev@greatscottgadgets.com > https://pairlist9.pair.net/mailman/listinfo/hackrf-dev
_______________________________________________ HackRF-dev mailing list HackRF-dev@greatscottgadgets.com https://pairlist9.pair.net/mailman/listinfo/hackrf-dev
_______________________________________________ HackRF-dev mailing list HackRF-dev@greatscottgadgets.com https://pairlist9.pair.net/mailman/listinfo/hackrf-dev
