If I connect a white noise generator to an antenna, does it reach 800 MHz to 2.7 GHz and thereby interfere with a cell phone?
Not in principle, because the noise is random, continually bouncing from frequency and filling the spectrum with a very wide frequency distribution. Thus, because of the type of modulation used in cell phones (frequency hopping) it can get rid of noise and function normally, even because the signal strength of a white noise generator would have to be too large to have any effect. A better way is to use an oscillator with good power that can scan the desired full range and vary its frequency by modulating it by varicap from a lower frequency external signal.
