What considerations should I take when ordering coils to work in above 1 GHZ region?

[actra]

the second prob in my 1.3 GHZ design is the coil...

its on coil conected in series with the input pin to the RF amp ,

the problem is ...its in 0603 package...the data sheets says its for H freq applications but dndt mention any parametrs to calculate the resonance frequ of the coil....

the second and the more imp paramter is ... the coil has a polarity but the one in design doesnt has polarity ? is it going to work ? or i sholuld replace it with non polarity coil ???

what considerations should i take when ordering coils to work in above 1 GHZ region ?



thanks in advance

 

[BigBoss]

polarity of coil ?

Did you use multilayer inductor at that frequency ? Propably it's so..
Don't use multilayer inductors over 1GHz.Some multilayers have polarity markings but I don't know why?? Normally air core or planar inductors have no polarity, maybe only to indicate the series of coils...

Multilayer inductors have lower SRF and high loss, so at 1.3GHz try to use air core or planar inductors from AVX or Murata..

 

[actra]

polarity of coil ?

its Air core multilayer coil from murata ... its datasheet is here
**broken link removed**

its suitbale for high frequency applications but they didnt specify its stray cap to calculate its SRF... but ithink it will work in 1.3 ghz...

the question is how to connect it since it has a polarity !!!!!!!
and the signal passing through it has negative and positive edges ..

 

[Mazz]

polarity of coil ?

Absolutely no polarity in inductors.
Only a mark, maybe giving a reference for magnetic flux, but i'm not sure.
SRF is specified in data sheet. Be aware of Q, it's also specified in the data sheet for some values. For example 10nH has Q>50 @ 1.3GHz.
If I well remember you can download S parameters of those inductors from Murata site to simulate them.
If it's for LNA matching network, it's OK.