Resistance and attenuation formulas of microstripline constructed by inspection and compared to results from different softwares

Fabricated in copper, a microstrip line section has a small but non-negligible distributed resistance and therefore line attenuation. In a large microstrip circuit of many line sections cumulative attenuation may be substantial. Therefore it is desirable to find with simple and accurate formulas for the distributed resistance and attenuation of a line section over all frequencies. The formulas are to be checked by popular softwares.