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I'm trying to design a wide band RF receiver(say 5MHz to 5GHz).

The antenna:

  • How long would the antenna have to be to pick up this range?
  • I read that the antenna width would have to be at least as long as the half wavelength so would I have to use a 30m antenna to receive a 5MHz signal?
  • Would I be able to pick up a 5GHz Signal with that same 30m antenna?
  • And to pick up the signal the circuit would have to have a resonant frequency equal to that of the RF signal?

Are there any good resources out there I should look at?

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    \$\begingroup\$ You've got way more than one question here. I'd suggest first asking just about the antenna. If you still think this is a viable project after learning more about that, then give us another question about the receiver circuit. \$\endgroup\$ – The Photon Sep 26 '12 at 4:27
  • \$\begingroup\$ half wavelength or λ/4 ??? \$\endgroup\$ – perilbrain Sep 26 '12 at 5:54
  • \$\begingroup\$ The Biconical antenna is often used for EMI detection purposes, but even that would be challenged over a 3 decade range. Do you want to accurately measure field strength or just detect the presence of RF. What field strengths do you expect? Are you limited to a single antenna? \$\endgroup\$ – MikeJ-UK Sep 26 '12 at 9:37
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If a very wide range of frequencies needs to be covered usually Log-peridoc antennas are used.

I doubt, however, if you can use one single antenna effectively to cover the range of 5MHz to 5GHz (factor 1000!).

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  • \$\begingroup\$ Ok thank you! so it looks like i'll need to use two antennas? \$\endgroup\$ – nwnoga Sep 28 '12 at 23:28
  • \$\begingroup\$ @nwnoga: I guess you need even more than 2. Some Log-periodic antennas can cover a range of factor ca. 10. I.e. in that case you would still need at least 3: 5-50 MHz, 50-500 MHz, 500-5000 MHz. \$\endgroup\$ – Curd Sep 30 '12 at 18:59

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