PCA10005 - SMA edge Antenna Impedance Matching

Question

Hello, 
 I am trying to create my own design using an SMA edge Antenna, and I am very closely following the Altium Design files provided by Nordic for PCA10005. 
 I have the layout almost complete, however, I am concerned about the trace that connects the L-C filter circuitry to the SMA jack connector. The trace width in the provided files is 30mils. However, using any online calculator, this trace impedance is not matched to 50Ohms. 
 Shouldn't the width of that trace be closer to 110mils to properly match the impedance of the antenna? 
 Thanks,
Michael 
 P.S. Would anyone happen to know the layer stack-up of PCA10005? I have searched the Hardware files but cannot find anything, and for that reason, used 1oz. copper to calculate the impedance. Thanks again!

Asbjørn · Accepted Answer

The trace between the discrete matching network on PCA10005 and the SMA is calculated by using the "CoPlanar Waveguide" calculator in "AppCAD" from Agilent/HP . You input the thickness of the substrate, what kind of substrate it is and it gives you the width of the trace you need in order to have a 50 Ohm trace. 
 The stack up of the PCA10005 is 1.6 mm thick FR4 with two layers. There's no inner layer on the PCA10005. 1 oz copper is what we use. 
 Also, if you want to Nordic support team to have a look at your design before you send it off to production, please register at www.nordicsemi.com/.../Support and upload your design files there.

PCA10005 - SMA edge Antenna Impedance Matching

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