Jun 17, 2011 #1 P pankaj.patil Junior Member level 3 Joined Mar 22, 2011 Messages 26 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,281 Activity points 1,457 Hello Sir How to measure Image Rejection Ration of Mixer ? Can you give me experimental setup to measure Image Rejection Ration of MIXER ? Thank You
Hello Sir How to measure Image Rejection Ration of Mixer ? Can you give me experimental setup to measure Image Rejection Ration of MIXER ? Thank You
Jun 17, 2011 #2 B biff44 Advanced Member level 6 Joined Dec 24, 2004 Messages 5,047 Helped 1,376 Reputation 2,748 Reaction score 1,056 Trophy points 1,393 Location New England, USA Activity points 37,907 You hook a spectrum analyzer to the IF output port, and drive the LO and RF inputs with a synthesizer. You set up Frf to be the desired signal and look at the IF out power level in dBm. You then set up Frf to be the image, but the same distance from the LO as the desired signal. You look at the IF out power level. The difference in the 2 IF out power levels is your image rejection.
You hook a spectrum analyzer to the IF output port, and drive the LO and RF inputs with a synthesizer. You set up Frf to be the desired signal and look at the IF out power level in dBm. You then set up Frf to be the image, but the same distance from the LO as the desired signal. You look at the IF out power level. The difference in the 2 IF out power levels is your image rejection.
Jun 17, 2011 #3 tony_lth Advanced Member level 5 Joined Jul 28, 2010 Messages 2,088 Helped 377 Reputation 756 Reaction score 368 Trophy points 1,363 Location Beijing Activity points 12,641 Sometimes using variable RF, somtimes using variable LO.
Jun 22, 2011 #4 P pankaj.patil Junior Member level 3 Joined Mar 22, 2011 Messages 26 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,281 Activity points 1,457 biff44 said: You hook a spectrum analyzer to the IF output port, and drive the LO and RF inputs with a synthesizer. You set up Frf to be the desired signal and look at the IF out power level in dBm. You then set up Frf to be the image, but the same distance from the LO as the desired signal. You look at the IF out power level. The difference in the 2 IF out power levels is your image rejection. Click to expand... Thank you biff44 At different Frf we get different Image Rejection, then which Image Rejection should consider? And what is theoretical formula to calculate image rejection ration to compare it with practical result? thank you
biff44 said: You hook a spectrum analyzer to the IF output port, and drive the LO and RF inputs with a synthesizer. You set up Frf to be the desired signal and look at the IF out power level in dBm. You then set up Frf to be the image, but the same distance from the LO as the desired signal. You look at the IF out power level. The difference in the 2 IF out power levels is your image rejection. Click to expand... Thank you biff44 At different Frf we get different Image Rejection, then which Image Rejection should consider? And what is theoretical formula to calculate image rejection ration to compare it with practical result? thank you