Murlix
Member level 2
Hi, I am Murali. I am doing 12Ghz LNA design using microstrip .I am using ATF36077 HEMT FET (avago) (Vds=1.5,Ids=10mA and Vgs=-0.2V) as the transistor and RO3010 pcb(Er=10.2).I am using ADS2005A for simulation.
I have attached the schematic of my design for your viewing.
I used Zin=15.547+j9.6410 and Zload =17.75+j4.99 for my design.
I set the TL6 and TL4 as the microstrip equivalent of RF choke inductor.
My goals for the design is gain>10dB[S(2,1))>10dB], noise figure<1dB.
I am getting 11.4dB for gain and NFmin=0.557 at 12GHz for my simulation.
My problem is that :
1)Is there anyway I can convert the decoupling capacitor in the design to microstrip equivalent?I heard a wide stub can be used to replace the capacitor but I dont know how to do it. I hope someone can help me in this area
2)I am unable to get the simulation results to be (S(1,1)) < -21dB and the (S(2,2)) < -21dB(to reduce reflected signal in the network).Optmization did not help much to achieve this target.
I hope you can guide me the way to troubleshoot the design.Thanks in advance.
I have attached the schematic of my design for your viewing.
I used Zin=15.547+j9.6410 and Zload =17.75+j4.99 for my design.
I set the TL6 and TL4 as the microstrip equivalent of RF choke inductor.
My goals for the design is gain>10dB[S(2,1))>10dB], noise figure<1dB.
I am getting 11.4dB for gain and NFmin=0.557 at 12GHz for my simulation.
My problem is that :
1)Is there anyway I can convert the decoupling capacitor in the design to microstrip equivalent?I heard a wide stub can be used to replace the capacitor but I dont know how to do it. I hope someone can help me in this area
2)I am unable to get the simulation results to be (S(1,1)) < -21dB and the (S(2,2)) < -21dB(to reduce reflected signal in the network).Optmization did not help much to achieve this target.
I hope you can guide me the way to troubleshoot the design.Thanks in advance.