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sviodo
Joined: 02 Jan 2002
Posts: 90
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 08 Mar 2003 19:17 microstrip - surface wave |
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hi, do you know by any chane where i can find siplified formula to compute frequency of surface wave rise?
I know sth like this: f=75/(h*(sqrt(er-1))) but don't know exact article...
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With Regards,
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g86
Joined: 21 Jan 2003
Posts: 208
Helped: 4
Location: On top of antenna :))
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| 08 Mar 2003 19:47 Re: microstrip - surface wave |
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How the frequency of surface wave changes with h or er? Is it power or intensity you are talking? Are you talking about the surface wave in planer configurations at RF or somthing else?
  
| sviodo wrote: |
hi, do you know by any chane where i can find siplified formula to compute frequency of surface wave rise?
I know sth like this: f=75/(h*(sqrt(er-1))) but don't know exact article...
--
With Regards, |
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sviodo
Joined: 02 Jan 2002
Posts: 90
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| 08 Mar 2003 19:59 |
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as i mentioned in topic the interest is microsrip structure which is of course planar in my case, the question refers to the maximum operating frequency without surface wave propagation. sorry if it was not clear eough.
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Sviodo
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loucy
Joined: 26 Aug 2001
Posts: 423
Helped: 10
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| 10 Mar 2003 16:01 |
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The formula should read f[GHz]<=75/(h[mm]Sqrt(er-1)) for single grounded dielectric layer. And this condition doesn't imply that there is no PROPAGATING surface wave. Instead, the dominant TM surface wave has zero-cutoff, and the above condition implies there is only this dominant TM surface wave propagating in a grounded dielectirc slab, all higher order modes are evanscent. This is not related to the metal trace. In orther words, metal traces (like the microstrip) are removed when doing this eigenvalue analysis.
The reference should be: J R Mosig and F E Gardiol, "A dynamical radiation model for microstrip structures," Adv. Electron. Electron Phys. Vol 59, pp.139-237, 1982.
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sviodo
Joined: 02 Jan 2002
Posts: 90
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| 10 Mar 2003 16:43 |
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thx a lot budy, that was exactly what i needed :>
With Regards,
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