Question

Calculation of attenuation micriostrip line

Answer 1

ADS microstrip loss trade study

For grins we used ADS to compare the losses of some different microstrip media, we chose some of our favoritehard substrate materials. If you want us to add to the list, make a suggestion! We separately calculated metal loss and dielectric loss tangent loss. The trick is to use infinite conductivity in one case, and tandD=0 in the other case. We'll summarize the data in tables below. Note that the calculation does not take into account surface roughness, or underplating. Also please don't send us arguments that ADS is not as accurate as HFSS for computing losses, that might be true but the error in this trade space is slight. BTW, some of the dielectric properties came from an old MIC Technologies catalog in case you were wondering about references...

Here's two tables on alumina (Al2O3). The first table is for 10 mil, the second one is for five mil. You'd only use five mil on millimeterwave jobs, (greater than 30 GHz). Check out the loss tangent loss, it is very nearly proportional to frequency. The metal loss closely follows the square root of frequency.