资料介绍
RF资料
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Balanced Amplifiers
The single amplifier meets the specification for noise figure and again but fails to meet the
return loss specification due to the large mis-matches on the input & outputs. To overcome
this problem one solution is to use a balanced amplifier topography, which is shown in Figure
1.
NOTE Dashed lines are reflected signals
Figure 1 Schematic diagram of a balanced amplifier using two quadrature hybrids (eg
Lange Couplers).
The balanced amplifier employs two quadrature hybrids in this case two lange couplers
(although branchline couplers can be used). Any reflections of an in