Abstract:
The invention enables a compromise between DC offset rejection and image rejection through the use of a bandpass filter having a variable center frequency.
Abstract:
A first low-noise amplifier is connected to a first receiving processing unit through a first cable and a bypass circuit is provided in parallel to the first low-noise amplifier so as to bypass the first low-noise amplifier. In the case that the intensity of broadcasting signal is more than a predetermined value, when the C/N is more than a first predetermined value and less than a second predetermined value higher than the first predetermined value, the broadcasting signal is transmitted to the first cable through the first low-noise amplifier, and when the C/N is less than the first predetermined value or more than the second predetermined value, the broadcasting signal is not input to the first low-noise amplifier but transmitted to the first cable through the bypass circuit.
Abstract:
Apparatus and methods for performing automatic gain control in a radar system. One embodiment of the system includes an attenuator that controls gain of signals received from a radar receiver. A digital signal processor determines coarse gain correction based on digitized noise data for a plurality of channels, determines fine gain correction based on the residual error after the coarse gain, and determines frequency vs. gain curve correction based on the digitized noise data for a plurality of channels and a mathematical model of frequency gain across a noise spectrum for the radar system. The result of the processor is a gain control signal that is sent to the attenuator to perform hardware gain control and a channel specific scale factor for software gain control. In one embodiment, the processor generates the gain control signal during an inactive scan mode of the radar system.
Abstract:
The present invention discloses a proactive gain control system for a communications receiver. The proactive gain control system includes a variable gain module for outputting an output signal in response to an input signal. A detector detects the output signal and outputs a detection signal representing a signal strength of the output signal. A traffic monitor monitors the output signal and outputs a traffic profile signal indicating that a traffic profile for the input signal will change. A gain computing module outputs a gain adjustment value in response to the detection signal and the traffic profile signal. A gain control module outputs a gain control signal to the variable gain module, which determines a gain between the input and output signals, in response to the gain adjustment value.
Abstract:
The invention enables a compromise between DC offset rejection and image rejection through the use of a bandpass filter having a variable center frequency.