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Dipole Gain in Basestation antenna

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but dipole length leads more than 8 lambda to achieve the required gain.
Needs additional filtering to suppress the unwanted signal too.

I guess it should be dipole array.
Base station requires sector covering and dipole may not be the right element to choose.
 

Hello,

No, when making the dipole longer you get a radiation pattern with many lobes. The lobe with highest gain is far from the horizontal plane.

If you accept directivity in the horizontal plane, you can place a fat dipole close to a large ground plane (so you make a sector antenna). when making the dipole 1.25 lambda long, you get highest gain (above 9.5 dBi).

Note that the input impedance is far from 50 Ohms, so you need to insert a matching section. Using a fat dipole (or wide strip type dipole) increases the usefull bandwidth.

In case of 9.5 dBi omnidirectional, you need a collinear array of about 6 elements.
 

lmd2010 said:
With the ground,it's possible to get 9.5dBi from a single dipole.
Click to expand...

I severely doubt it , please show me your evidence, I'm always willing to learn :)

A standard 1/2 wave dipole has a gain of 2.15dBi only way to get more gain from a single 1/2 wave dipole is to put it in from of a reflector ... say a dish or a corner reflector
other wise as others have stated you need to use multiple dipoles in a phased array
as also stated dipoles of 1 wavelength or more are not usually used cuz of the assoc. problems

Dave
 

lmd2010 said:
With the ground,it's possible to get 9.5dBi from a single dipole.
Click to expand...

We are getting 7-8 dBi gain with ground (reflector plate). Please let me know if you have any paper etc to get 9+ dBi gain over 25% bandwidth. I need to use this for cross polarized antenna (+-45; dual linear)
 

For "davenn": 2*0.5 or 2*0.625 lambda configuration is also a dipole. With these configurations over a large ground plane, you will exceed 9.5 dBi. Just put one in a simulator and you will be convinced.

The problem is that for the highest gain, the dipole must be close to ground and that may result in too low useful bandwidth.
 

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