|Electromagnetic radiation class||Frequency||Wavelength||Energy|
|Ionizing radiation||γ||300 EHz||1 pm||1.24 MeV|
|30 EHz||10 pm||124 keV|
|HX||Hard X-rays(100-200pm)||3 EHz||100 pm||12.4 keV|
|SX||300 PHz||1 nm||1.24 keV|
|30 PHz||10 nm||124 eV|
|3 PHz||100 nm||12.4 eV|
|300 THz||1 μm||1.24 eV|
|30 THz||10 μm||124 meV|
|Radiowaves||3 THz||100 μm||12.4 meV|
|300 GHz||1 mm||1.24 meV|
|EHF||Extremely high frequency|
|30 GHz||1 cm||124 μeV|
|Microwaves||SHF||Super high frequency|
|3 GHz||1 dm||12.4 μeV|
|UHF||Ultra high frequency|
|300 MHz||1 m||1.24 μeV|
|VHF||Very high frequency|
|30 MHz||10 m||124 neV|
|3 MHz||100 m||12.4 neV|
|300 KHz||1 Km||1.24 neV|
|30 KHz||10 Km||124 peV|
|VLF||Very low frequency|
|3 KHz||100 Km||12.4 peV|
|ULF||Ultra low frequency|
|300 Hz||1 Mm||1.24 peV|
|SLF||Super low frequency|
|30 Hz||10 Mm||124 feV|
|ELF||Extremely low frequency|
|3 Hz||100 Mm||12.4 feV|
Note: Electromagnetic waves with a wavelength of 1 to 10 millimetres (1 cm), are called millimeter waves (millimetre band), abbreviated MMW or mmW
Excerpt from link: http://www.strixsystems.com/cshealthconcernsaboutwifi.aspx
"Whereas most cell phones have a peak power output of 2 Watts (some at 3), most Wi-Fi routers have a peak power output of less than 100mW which is typical of indoor access points, and 400 or 500mW for outdoor units, but unlike cell phones and their base stations, Wi-Fi devices do not communicate continuously. Dr. Kenneth Foster, a professor of bioengineering at the University of Pennsylvania, recently completed a study of Wi-Fi, taking over 350 measurements at 55 sites across four countries. According to his research, not only does Wi-Fi equipment emit less radiation under load, it does so in much smaller bursts. “When the networks were not being used, the duty cycle was 0.01 percent or so. That means that it is radiating power for 0.01 percent of the time.” While Wi-Fi and microwaves use the same 2.4 GHz frequency, a microwave oven sends much more intense emissions than a Wi-Fi deviceor cell phone."
(link shared by Robert Duncan)
On process of certification by the FCC to be able to market software-defined radio in the US.
Link from IEEE
http://spectrum.ieee.org/geek-life/hands-on/a-40-softwaredefined-radio says "Which brings us to regulatory issues. In some countries, it’s illegal to receive any frequency you don’t have a license for, apart from public broadcast frequencies. In the United States, you’re free to pick up nearly all the signals you can receive. There are, however, important exceptions to this general rule, such as a ban on listening to cellphone frequencies, or operating equipment capable of picking up police signals while you’re in a vehicle (the latter is permitted with a ham license)."
Comment from http://hackaday.com/2015/02/12/why-you-should-care-about-software-defined-radio/
RTL-SDR can pick up any signal that would be receivable at your location anywhere between 24 MHz and 1700 MHz if you have the most common type of RTL-SDR (RTL2832 + R820T chipset) and a good antenna. With software such as SDR# (my personal favorite), you can take a good look any of those signals. Will it DECODE cell signals? Definitely not. Also, doing so in the US is technically illegal. Things may be different if you live in another country, so check your local laws.
Indicative dongle and software
https://www.amazon.fr/NooElec-NESDR-Mini-T%C3%A9l%C3%A9commande-antistatique/dp/B00VZ1AWQA/ref=sr_1_fkmr0_2?s=electronics&ie=UTF8&qid=1487243127&sr=1-2-fkmr0&keywords=puce+R820T2 et ce logiciel https://play.google.com/store/apps/details?id=marto.androsdr2. Merci d'avance.
Radiofrequency Sweep or Scanning
"Radio frequency sweep or "Frequency sweep" or "RF sweep" refer to scanning a radio frequency band for detecting signals being transmitted there. This is implemented using a radio receiver having a tunable receiving frequency. As the frequency of the receiver is changed to scan (sweep) a desired frequency band, a display indicates the power of the signals received at each frequency."
Video demonstrating sweep of the FM band
Analyse par balayage (scanning) fréquentiel (pour exploration spectrale)
Il faut noter que la vitesse de balayage influence la résolution spectrale.
Analyseur de champ électromagnétique
Un analyseur de champ électromagnétique est un instrument de mesure regroupant deux capteurs :