Andryuha
Member level 4
I am modelling a microstrip resonant antenna and need to feed it with coax cable through the substrate in the middle.
I have 2 questions:
1)Can you guess some SMA compatible realistic 50 Ohm cable parameters? a)Signal conductor (inner) diameter "ID" b)Insulator (outer) diameter "OD" c)Insulator dielectric permittivity and loss tan.
It appears easy to find a cable, but hard to find detailed datasheet... especially distributed dielectric permittivity of composite insulator is never explained.
2)When feeding the 50 Ohm microstrip line somewhere in the middle of circuit, what should be a diameter of hole in the ground plane? I've seen some textbooks telling that the hole should be smaller than OD. But I've seen no explanation why, or any formula.
I have 2 questions:
1)Can you guess some SMA compatible realistic 50 Ohm cable parameters? a)Signal conductor (inner) diameter "ID" b)Insulator (outer) diameter "OD" c)Insulator dielectric permittivity and loss tan.
It appears easy to find a cable, but hard to find detailed datasheet... especially distributed dielectric permittivity of composite insulator is never explained.
2)When feeding the 50 Ohm microstrip line somewhere in the middle of circuit, what should be a diameter of hole in the ground plane? I've seen some textbooks telling that the hole should be smaller than OD. But I've seen no explanation why, or any formula.