LPDA antenna problem

[nikkv886]

Hello!
I want to design an antenna that works good in four different frequences (930MHz, 1880MHz, 2150MHz and 2400MHz). I'm thinking about making a LPDA that has four elements, each adjusted for the different frequences.

My first question is if this is a good solution or is there a better way to design an antenna with these features?

If it's possible to design the antenna this way, what is the minimun
distance between the elements?

BR
Niklas

 

[Al42]

What services are you designing for? I can't think of any particular kind of service that would be present on all bands. (And it's easier to get gain at the 3 higher frequencies with other designs.)

 

[nikkv886]

Thanks for answering, I'm building a high frequency power detector, that can cover all of the above mentioned bands. I want to keep down the size as much as possible.
Any ideas ???

 

[IXNAY]

Lpda

It would be impractical to build an LPDA at S band. For the home builder, a biconal or discone might be broadband enough to cover those frequencies.
Typical L and S-band antennas are dish or corner reflector with a waveguide feed. A dipole feed can be used a L band, but the dimensions must be close. These are single band antennas.
For simple power detection, a reflector with a voltage probe feed and an LNA would work broadband. A microwave detector diode and voltage amp would give a relative DC value of the received signal.