The Humm Noise ? answear hear!

a noise in atmosphere worldwide ?
no one knwos what it is ? They call it the Humm .
It could come from Haarp and sations like that in addition to the infos you find on the www.itu.int .
they know it !
here is the answear !
please read the full pdf if you really want to understand it like i did. 138 pages .

http://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-BO.955-3-1994-PDF-E.pdf
( http://cordis.europa.eu/infowin/acts/rus/projects/ac348.htm -- i was looking for that ac348 named in videowarning ( https://www.youtube.com/channel/UCfL3IsqG1kRmdAeNr9K6X6Q )
what i thought sounds like bullshit , and yes i think its no chemical name. but maybe a warning and maybe it is something what could make us sick in addition too what we know about ELF and HAARP or things like that . lowfrequency or ionosphere are other r´topics ) (  http://www.informatik.uni-trier.de/~ley/pers/hd/f/Filali:Fethi )



its an  interference .
that happend when:
satellite channel are usually described in terms of the multipath delay spread and correlation
bandwidth. The delay spread To is a measure of the duration of an average power delay profile of the
channel. The correlation bandwidth Bc is the bandwidth at which the correlation coefficient between
two spectral components of the transmitted signal takes a certain value, say 90%. The empirical
relationship between the correlation bandwidth at 90% correlation and the delay spread is given in §
4.1 of Annex 2.
Considering a simple digital modulation system operating in a frequency selective channel,
the error performance is dependent upon the spread of delays introduced by the different paths, as
well as by the amplitude of the component signals. Assuming that each wave is affected by a
multiplicative Rayleigh process [Pommier and Wu, 1986], with an exponential distribution of delays
of standard deviation, To, a level of intersymbol interference will be introduced which depends upon
the delay-spread to the symbol-period ratio, Tr (i.e. the ratio, To/T, where T is the duration of the
modulation symbol).




study was made on the practical implication of such additional interference from the
nearby satellite beam (CCIR, 1990-1994, Doc. 10-11S/128). It is assumed that the geostationary
satellite is on the same channel as the terrestrial service and uses the same type of modulation. It is
also assumed that this interference is seen by the receiver as additive uncorrelated white Gaussian
noise, therefore adding to the thermal noise level in the receiver. It is found that, using the RARC-83
co-polar reference pattern for the satellite antenna, the apparent noise increase in the receiver is less
than 1 dB for a receiver located beyond a relative angle seen from the satellite of φ/φo = 1.4 where φo
is the half power beamwidth. The apparent noise increase becomes 3 dB at φ/φo =1.2 and 7 dB at φ/φ


 9 -
Rep. ITU-R BO.955-3
satellite channel are usually described in terms of the multipath delay spread and correlation
bandwidth. The delay spread To is a measure of the duration of an average power delay profile of the
channel. The correlation bandwidth Bc is the bandwidth at which the correlation coefficient between
two spectral components of the transmitted signal takes a certain value, say 90%. The empirical
relationship between the correlation bandwidth at 90% correlation and the delay spread is given in §
4.1 of Annex 2.
Considering a simple digital modulation system operating in a frequency selective channel,
the error performance is dependent upon the spread of delays introduced by the different paths, as
well as by the amplitude of the component signals. Assuming that each wave is affected by a
multiplicative Rayleigh process [Pommier and Wu, 1986], with an exponential distribution of delays
of standard deviation, To, a level of intersymbol interference will be introduced which depends upon
the delay-spread to the symbol-period ratio, Tr (i.e. the ratio, To/T, where T is the duration of the
modulation symbol).


http://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-BO.955-3-1994-PDF-E.pdf