Filtering Out The Unwanted Mixing Product - HP 8711C User Manual

Making Measurements
Measuring Conversion Loss
Inserting a 700 MHz bandpass filter in the measurement setup removes the
unwanted signals at 200 MHz, 900 MHz and 1100 MHz, providing an accurate
measurement of the desired IF signal at 700 MHz.
In the following example, the conversion loss of a mixer will be measured
with RF input frequencies over a 15 MHz span centered at 900 MHz. With an
LO frequency of 200 MHz, the mixer IF frequency will sweep over a 15 MHz
span centered at 700 MHz.
3-36
深圳市盛腾仪器仪表有限公司
LO
Pwr
2 0 0
MHz
Figure 3-13. Filtering Out the Unwanted Mixing Product
Tel:0755-83589391
7 0 0
M H z
2 0 0 7 0 0
900
MHZ MHz MHZ
( R F - L O ) ( R F ) (RF+LO)
Fax:0755-83539691 Website: www.Sengt.c