# Search results

1. ### question on LNA stability

Thanks pancho_hideboo, enjunear and DDavid, Finally, after I break the 200pF capacitor to 10 20pF capacitors, the problem is solved. The stability looks the same as the ones with ideal model. But I still have a question about the capacitor, I did a test on the muRata capacitor I found...

3. ### question on LNA stability

Hi Guys, I am designing an LNA at 2.4 GHz. I am a beginner. The transistor is NEC3210S1. When I use an ideal capacitor c7=200pF, the stability is OK(the second picture). But when I changed to a real capacitor model ATC700B201JP300 200pF, the stability became worse(the third picture). I tried...
4. ### cannot get .hb file from HSPICERF

Hi Everyone, I try to run an example from hspice@RF user guide. It is example 2, Power Amplifier. .options POST accurate .param f0=950e6 PI=3.1415926 Ld=2e-9 Rload=5 Vin=3.0 .param Lin=0.1n Vdd=2 Cd='1.0/(4*PI*PI*f0*f0*Ld)' M1 drain gt 0 0 CMOSN L=0.35u W=50u AS=100p AD=100p +PS=104u PD=104u...

HFSS and designer Hi, I have two microwave components to simulate. But it is difficult to simulate with HFSS. So I want to extract the data to designer and simulate. I don't know whether it is data link or dynamic link. Does anyone have some example that I can follow? Thanks!
6. ### T-junction power divider

Hi everyone, I want to design a T junction power divider from 12GHz to 24GHz. But there is always a resonance peak at about 21GHz. Then I change the length of the arms, the peak can move a little bit according to it. Does anyone can help me to figure it out? I set up one port as 25ohm, and the...
7. ### FDFD method to solve eigen value problem

how to solve tm mode Hi Iyami I am sorry to tell you that I am analyzing the magnetic material. So I guess it is not easy to split it into TE and TM modes. And I didn't include the boundary fields. Yet I am very interested in how to split into TE and TM, and how to combine them. Do you get...
8. ### FDFD method to solve eigen value problem

fdfd method Janklinux: Thanks for your advise. I am using FDFD to analyse some microwave device.　I have another questions. How to specify the boundary condition for a microstrip line? Thanks! Iyami: since I use all the 6 field components. The total number of the equations is 143041. Thanks!
9. ### FDFD method to solve eigen value problem

fdfd method Hi Everyone, I am using FDFD method to solve eigen value problem, like a microstrip line. The software I am using is Matlab. But when I refine the mesh, say 200 by 120, the final matrix would be 143041 by 143041. The matlab cannot handle that. Anyone have a good idea to solve...
10. ### How can Labview help developing MCU

Hi, can anyone do me a favor to describe how labview can help develpoing MCU. I am new to MCU, and I heard labview can make it easy. Better describe in detail in hardware and software. Thanks !
11. ### questions about moment of method

Hi adel_48, Thanks for your response. By zeros I mean the zeros for determinant of the homogeneous equation. My unknowns are included in the coefficients of the homogeneous equation group. By setting the determinant to be zero, I can get the unkowns, in my case, the phase constant. By it is...
12. ### questions about moment of method

Hi guys, I need help regarding moment of method. At the last step, I already got the mattrix for a homogenous equation group. And by setting the determinant to be zero, I can get the unkowns, such as the phase constant. My questions is, for a high order equation ( The number of the basis...
13. ### full wave analysis with Fourier series

Hi everybody, I meet a big trouble when I want to analyse the microstrip with full wave analysis. Attached is a paper about that method. I don't want to use the new method metioned in that paper. I just want to use the traditional method, which is the first part of that paper. I appreciate...
14. ### energy of the even mode and odd mode in coupled MSL

site:www.edaboard.com even odd mode Hi everyone, I am studying coupled microstrip lines right now. And I am confused by a questions. Do the energy of even mode and odd mode equal to each other when the V1=1v, V2=1v (voltage on each strip)for even mode and V1=1v, V2=-1v for the odd mode...
15. ### analytical expression of electric field in microstrip line

Re: analytical expression of electric field in microstrip li Hi babinton, Can you tell me which reference book or paper have the analytical solution and the procedure to get it. Thank you very much! pudding
16. ### analytical expression of electric field in microstrip line

Hi everybody, Is it possible to get an exact analytical expression of the eletric field and magnetic field in a microstrip line? Thanks! pudding
17. ### HFSS simulation result fidelity

navuho: Thank you very much. Good luck! pudding
18. ### HFSS simulation result fidelity

Hi navuho, I appreciate your help. Your comments are very precious for me. Yet I still have some questions: 1. you told me to do mesh refinement inside a substrate. Do I also need to refine the ground and metal's mesh inside? 2. I define the airbox according to the rule that the...
19. ### accuracy of waveport for microstrip in HFSS

I also met this problem before. Then I increase the length of the ms, and change delta S from 0.02 to 0.01, the two port impedance seems quite the same. But I also want to know what's going on there. Good luck!
20. ### HFSS simulation result fidelity

Hi xibilian, I simulate again with solution frequency 3GHz, 3.1GHz, 3.2GHz, , but the result still change too much. Do you have some example that the results are consistant to solution frequency? I attached my file again. By the way, would anyone like to check my file? I wonder there is some...