Method and apparatus to independently control front end gain and baseband gain

摘要

The invention may provide a receiver including a front-end block to provide a front-end gain on a radio-frequency input signal. The front-end block may include a mixer to convert the radio-frequency input signal to a baseband signal. The receiver also may include a wide-band peak detector coupled to the front-end block and a baseband block to provide a baseband gain on the baseband signal. An analog-to-digital converter may convert the baseband signal to a digital signal. The receiver may further include narrow-band peak detector coupled to an output of the analog-to-digital converter. An automatic gain control circuit may independently control the front-end gain and the baseband gain based on outputs from the wide-band peak detector and narrowband peak detector.

主权项

1. A receiver, comprising:
a front-end block to provide a front-end gain on a radio-frequency input signal, the front-end block including a mixer to convert the radio-frequency input signal to a baseband signal; a wide-band peak detector coupled to the front-end block; a baseband block to provide a baseband gain on the baseband signal; an analog-to-digital converter to convert the baseband signal to a digital signal; a narrow-band peak detector coupled to an output of the analog-to-digital converter, wherein the narrow-band detector includes at least two comparators to detect a saturation level of the analog-to-digital converter, a first comparator using a low saturation threshold and a second comparator using a high saturation threshold, wherein the low and high saturation thresholds correspond to different saturation levels of the analog-to-digital converter; and an automatic gain control circuit, to independently control the front-end gain and the baseband gain based on outputs from the wide-band peak detector and narrowband peak detector.