ADS Impedance Matching Design with Tool

Hi all,

Could anyone provide some tutorial/advice how to design an impedance matching section using the Impedance Matching Utility (IMU) of ADS when S-Parameter files are available? Say, I have two S-Parameter files/blocks which I would like to match to each other with a defined bandwidth and loss, so I am using the LC_BandpassMatch Smart component and the IMU for this purpose. It then calculates some possible matching networks but when I implement the circuit as a whole (Input --> SP_Block1 --> ADS_Matching --> SP_Block2 --> Output) it does not seem to provide the desired broadband matching at all.

I tested this by terminating the SP2_Block at 50 Ohms and looking at the input impedance of the combination ADS_Matching/SP2_Block, which should be more or less equal to the complex conjugate of my SP1_Block output impedance over the desired bandwidth when the input is terminated at 50 Ohms, but it is not the case.

What am I missing here? Any tutorial or info will be of great help.

Thanks!

hi,
i have solved many impedance matching problem before. based on my experience, IMU is not great! i always end up using smith chart utility which is easy and if you match to you centre frequency, you will preety much able to match the whole band! best of luck!

I use the smith chart tool too, but for mm-wave broadband matching the matching bandwidth is typically not sufficient with a simple LC network. That's why I would like to get it working with the IMU, but I'll check it out anyway. Thanks!

you have calculate your circuit Q and insert it in the smith chart utility. if your elements does not exit the Q of the circuit, you will surely can meet the bandwidth. you will know how many LC you need to have in order to meet the bandwidth..