ya.. its about matching problem! anyway, i m not really know how to calculate L1, how long it should be?? and the distance between substrate and patch must greater than lamda over 4??
ya.. its about matching problem! anyway, i m not really know how to calculate L1, how long it should be?? and the distance between substrate and patch must greater than lamda over 4??
2) another type of matching: - The L1 you must find it experimentally.
ad 1) - length of λ/4 transformer is λ/4 . You can see at the , there is all about λ/4 transformer
I wrote:
You must use software TXLine
1) find impedance your microstrip antenna - easy, set right colum "Physical Cahrakteristic" and click left arrow - you have impedance Zm
2) calculate Zx = √(Zm*50), this is impedance λ/4 transformer
3) in left colum set Zx, electical length is 90 deg - click right arrow and you have design λ/4 transformer
4) set left colum 50 Ω and you have feedline. In this case the length of feedline is
not important, you can have it 50 mm or 50 cm or 4.35 km (if you have loss free material)