p1 db? - RF Cafe Forums

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Peter_Bateman
 Post subject: p1 db?
Posted: Tue Nov 22, 2005 9:49 pm 
output p1 I know how to measure Op1dB on a vna using power sweep but am trying to figure it out using Sig gen and power meter. (wich one is more accurate?) I am thinking you reference the output power on the PM then increase the input pwr by 10 and wait till i only get 9db but that seem's to me to be a hard way.

Thanks in advance for any help and input.
 
  
 
Kirt Blattenberger
 Post subject:
Posted: Wed Nov 23, 2005 12:22 am 
 
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Joined: Sun Aug 03, 2003 2:02 pm

Posts: 476

Location: Erie, PA

Greetings Peter_Bateman:

Both the VNA and the signal generator + power meter methods should produce the same results provided the test is carried out properly. Be certain to obtain a reference gain for the device under test (DUT) while it is operating well within the linear operating region, and with the input reference signal at least 20 dB above the noise floor - ideally filtered to the BW of the system operational BW. Then, as you state, find the output power at which the gain of the DUT is 1 dB less than the linear gain. Making the measurement with the signal generator + power meter really does not take long if you are only testing a few devices.

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Posted  11/12/2012