Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

How to convert S11and S22 to complex impedance

Status
Not open for further replies.
T

thanhvktpk

Newbie level 4
Newbie level 4
Joined
Sep 20, 2008
Messages
7
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,283
Location
Viet Nam
Activity points
1,323
converting s11 to impedance

Dear all.
I'm a new comer, i wish to learn alot from you.
I have designed a PA module using BLF278. but datasheet only give me S11,S12.S21.S22 and I need convert to Zin and Zout in complex impedance. (or how to use S-paramter)
Please help me
Thanks
 

s11 impedance

Z = (1 + ρ)/(1-ρ)

ρ = (Z-Z0)/(Z+Z0)

Z0 is usually 50 ohms. These calculations are, of course, complex.
 

convert s11 to impedance

Thanks you very much for so many helps.
But BLF278 only give me S11 and Φ; (see table). I must convert to Zs and Zl in complex impedance.
Thanks.
 

s11 convert s22

Maybe I wasn't clear enough.

Zin = 50*(1 + S11)/(1 - S11)

And

Zout = 50*(1 + S22)/(1 - S22)

where Zin and Zout are the impedances looking INTO the device. You have to mutiply by 50 to convert the normalized impedance into ohms (assuming your S parameters were measured on a 50 ohm network analyzer).

The table you published has S11 as mag[s11] and ang[s11] for various frequencies. These are complex numbers. You do the complex division, one frequency at a time, and the answer is also a complex quantity, either in magnitude and angle, or Real and Imaginary parts, depending on how you choose to do the arithmetic.


Rich
www.MaguffinMicrowave.com
 

s11 conversion to impedance

See below:
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top