Antenna, transmission line

  1. 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. jcsd
  3. chroot

    chroot 10,427
    Staff Emeritus
    Science Advisor
    Gold Member

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

    - Warren
     
  4. How can I determined these odd integer harmonics ? and if is another wave form ? And the calculation of the power of these harmonics ?

    Thanks,

    Mica
     
    Last edited: Sep 8, 2004
  5. chroot

    chroot 10,427
    Staff Emeritus
    Science Advisor
    Gold Member

    http://mathworld.wolfram.com/FourierSeriesSquareWave.html

    Look at equation 6.

    The third harmonic has a frequency three times that of fundamental, and has an amplitude one-third that of the fundamental. The fifth harmonic has a frequency five times that of the fundamental and an amplitude one-fifth that of the fundamental.

    - Warren
     
  6. 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
     
Know someone interested in this topic? Share a link to this question via email, Google+, Twitter, or Facebook