designing a hbf is inverting the g values in lpf, the inductance become capacitance and vice versa and we will have actual capacitance values expressed in picofarads and microstrip lines .there is a very good worked example for a hpf in the book(microwave solid state circuit design) by inder...
i have a software to design a radial microstrip stub please send me your e-mail so that i can send you the programm .
suhair al-ali
suhair@coolgoose.com