Propagation modes in lossy cylindrical structures

The purpose of this communication is to calculate the orders of the Bessel functions that satisfies the equation f/sub v/(r)=J/sub v/(k/sub r//spl middot/r)+A/sub v//spl middot/Y/sub v/(k/sub r//spl middot/r) when the contour conditions are f/sub v/(a)=f/sub v/(b)=0. We will see that when k/sub r/ is a constant then the orders v may be complex.