Microstrip line simulations in Momentum

[nikosnte]

Hi, i would like to design microstrip lines that have the same physical length but i also want them to reach a common vertical limit so i have to bent some of these lines. Does anyone know how to calculate the length of a bent line? For instance if i construct a line consisting of parts using the curve model of momentum with pi/2 angle and some radius how can i calculate the length of these parts to control the overall length of the line??

 

[vfone]

In a curved microstrip line when the curving radius is larger than 2x width of the line, the main parasitic effect is a change in the effective line length.

If the radius is equal or less than the width of the line (case generally avoided) there will be a change in the effective lenght, will be a change in the impedance of the line, and a change in the phase response of the line. Also in this case the line is more affected by the substrate height and Dk variations.

Simulators for microstrip curve models should be fine, but best results can get doing a full EM simulation.