| 摘要 |
Apparatus and method for a limiting amplifier with improved phase noise. The improved limiting amplifier includes an input port, an output port, and one or more cascaded gain stages. The input of a first gain stage is connected to the input port of the limiting amplifier. The output of a last gain stage is connected to the output port of the limiting amplifier. Among the cascaded gain stages, an output of each gain stage is connected to an input of an adjacent gain stage. Each gain stage i, 1<i<n−1, is configured so that it is capable of selecting at least one lowpass filter corner frequency ωpi, and thereby reducing the phase noise of the gain stage through the broadband noise reduction for frequencies greater than ωpi. Here, ωpi is selected from a plurality of values associated with the gain stage to optimize the phase noise of the limiting amplifier by trading off reducing the broadband noise of the gain stage versus maintaining a sufficient output slew-rate of the gain stage. |
