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.

Insertion Loss & Return Loss [hlp]

Status
Not open for further replies.

No one

Full Member level 5
Joined
May 11, 2005
Messages
287
Helped
4
Reputation
8
Reaction score
2
Trophy points
1,298
Activity points
3,425
Hello everyone;
Suppose a two-port network with scattering parameters. Please express Return Loss & Insertion Loss by scattering parameters.
 

flyhigh

Advanced Member level 1
Joined
Nov 12, 2003
Messages
409
Helped
68
Reputation
136
Reaction score
29
Trophy points
1,308
Location
somewhere over the rainbow
Activity points
4,775
Hi,

Insertion loss is S21 [dB]
Return Loss(es) are -S11 [dB] and -S22 [dB] (minus sign, they are expressed as positive values)

flyhigh
 

g579

Full Member level 6
Joined
Dec 31, 1999
Messages
322
Helped
19
Reputation
38
Reaction score
4
Trophy points
1,298
Location
Somewhere
Activity points
2,470
Just a small correction.
Insertion loss is -S21 [dB]
 

    No one

    Points: 2
    Helpful Answer Positive Rating

Element_115

Advanced Member level 2
Joined
Mar 23, 2002
Messages
509
Helped
72
Reputation
144
Reaction score
43
Trophy points
1,308
Activity points
3,759
S21 is the Gain of the two port device! Pout/Pin
If it is a lossy or passsive device the gain will be zero or negative (Insertion Loss).
If it is an active device it should have some gain, making it a Positive S21

S11 is the Input ReturnLoss Looking in to Port 1 Pin(forward)/ Pin(reflected Back)

S22 is the Output Returnloss Looking in to Port 2 P(forward)/ P(reflected Back)

When S11 & S22 are Very Negative (dB) That means that none of the power going
in to the port get reflected out!
 

enark

Newbie level 4
Joined
Feb 20, 2006
Messages
5
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,333
S11 is the Input Return Loss and S22 is the Output Return Loss ONLY if S12=0 !!!
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top