
#1
Sep804, 10:46 AM

P: 32

Hi,
I want to clarify some notiona in an antenna. The major components of an antenna are a generator, transmission line and an antenna (dipole). Let's say the whole system has a perfect matche, i.e. the dipole is about 70 ohms as the transmission line. If my generator ,the output voltage, is an impulse which has a duration in a micro second ( let's say 1 micro sec). So, the frequency of this generator is 1 Mhz? If the impluse is a square, the main fundamental frequency is 1 MHz and also , with others harmonics, I means if I do the Fourier Transformation am I right? Thanks, Mica 



#2
Sep804, 01:06 PM

Emeritus
Sci Advisor
PF Gold
P: 10,424

A square wave is composed of odd integer harmonics. The third, fifth, seventh, and higher order odd harmonics all have power in them.
 Warren 



#3
Sep804, 03:10 PM

P: 32

Thanks, Mica 



#4
Sep804, 03:54 PM

Emeritus
Sci Advisor
PF Gold
P: 10,424

Antenna, transmission line
http://mathworld.wolfram.com/Fourier...quareWave.html
Look at equation 6. The third harmonic has a frequency three times that of fundamental, and has an amplitude onethird that of the fundamental. The fifth harmonic has a frequency five times that of the fundamental and an amplitude onefifth that of the fundamental.  Warren 



#5
Sep904, 03:13 PM

P: 32

Thanks for the information. So, for my dipole radited efficiently, I just match the right frequency output of the generator ? I mean like if my dipole resonances at 1 GHz so, my impluse (voltage source) duration will be 1/1 GHz ( 1 nano second) independent of the wave form?
Mica 


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