| 摘要 |
<p>A method and apparatus for providing a constant loop bandwidth of a power control loop system at different power levels. The present invention generates a power control loop output signal using series attenuators. The power output signal is processed in a power control loop to generate an attenuator control signal, wherein the attenuator control signal providing a constant loop bandwidth that is independent of the power level of the power output signal. To provide a constant loop bandwidth that is independent of the power level, a processor circuit such as a square root circuit is coupled between the output of the controller and the two series attenuators. The processing circuit processes the control signal to generate an attenuator control signal. The attenuator control signal provides a constant loop bandwidth that is independent of the power level of the power control loop output power signal, Pout. For example, the square root circuit receives the output from the controller Vc and the output Vs of the square root circuit controls the PIN diode attenuators, where Vs=Vc1/2. Alternatively, the square root circuit may be positioned between the detector/linearizer and the comparator.</p> |
