can share your experiences in basestation antenna design

[XuQing]

Hi ALL,

I design a 5-elements dipole antenna array for basestationantenna use. But the VSWR is not as good as simulation results from HFSS. Can anyone share your experiences in BSA design ?

Best Regard,
XuQing[/b]

 

[djalli]

Maybe I can help. Can you provide more info on what you are doing?

 

[XuQing]

djalli,

I use air-filled microstrip-line to feed signal and coupling to diple with a gap. Results from HFSS9.0 as follows.
Simulation: VSWR <1.3
Test: VSWR(max) =1.65
I'm not sure what's the most reasons.
1) due to HFSS errors
2) due to machining
3) due to design method
4) else
How do you think about this problem?

thank you!

 

[flatulent]

It could be your air filled transmission line. Is the method of supporting the conductor above the ground plane included in your simulation? Another thing to do is get the input impedance real and imaginary part in both simulation and measurements. This will give you more clues than a single number (SWR) parameter.

 

[XuQing]

flatulent,

Yes, I included the dielectric supporting in my simulation. But test is not in an anechoic chamber. Is that important in SWR testing?
Another case is I must enlarge the arm of dipole 20mm long than simulation data to get a tradeoff return-loss response.
Some wrong happens in simulation?

thank you!