The attenuation constant Ξ± of a transmission line, neglecting radiation loss, is given by: πΌ = πΌd+ K*πΌc where Ξ±d is the attenuation due to dielectric loss, K is the surface roughness coefficient, and Ξ±c is the attenuation constant due to ohmic loss per unit length:πΌ = ππ/ 2π10π10 = 2ππππ3β|π΄10| 2 /4π2 Re(π½)pπ = πΎ [π π β« |π½sy| 2 ππ¦ + π s β« [|π½sx| 2 + |π½sz| 2 ]]ππ₯ p10 is the power flowing through the waveguide for the TE10 mode defined. Pl is the power lost per unit length. To calculate power in tapered dielectric-filled rectangular shape structures with size variations in each section, how to determine the rate of change of attenuation constant?