| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve a radio receiver's immunity to interference. <P>SOLUTION: If the power level of a received signal meets or exceeds a predetermined power threshold, the low noise amplifier is by-passed, thus increasing the intercept point of a receiver. Alternative embodiments include the use of an RF power detector to control the front-end gain as a function of interference power. Continuous gain control allows the interference suppression and sensitivity of the receiver to be adjusted at lower signal levels than the switchable gain block. The processing device of the receiver measures the gain change in the IF signal power. If the change is less than the predetermined amount, the CDMA signal and interference power are below the noise floor and, therefore, the gain is increased. If the IF signal power change is greater than the predetermined amount, the interference is evident and the gain is reduced to reduce the intermodulation products. This process is used until the receiver is operating at the best compromise between interference and noise figure. <P>COPYRIGHT: (C)2008,JPO&INPIT |
