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: A SCSI ID of a SCSI initiator device that has won an arbitration is identified on a SCSI bus and stored in a register at a SCSI device. Subsequently, a SCSI ID of a selected SCSI target device which was selected by the SCSI initiator device is identified on the SCSI bus and compared with the SCSI ID in the register. If the SCSI ID of the selected SCSI target device and the SCSI ID stored in the register are different, a SCSI command from the SCSI initiator device is processed by the selected SCSI target device. If the SCSI ID of the selected SCSI target device and the SCSI ID stored in the register are the same, the selected SCSI target device refrains from processing the SCSI command from the SCSI initiator device.

Abstract: A system, method, and computer program product that performs self-calibration of pulse-compression radar signals. The system includes an antenna, a receiver, a transmitter, and a radar signal processor. Under normal (non-calibration) operation the radar transmitter generates a pulse compression waveform and transmits it via the antenna. Any reflections from this waveform are detected by the same antenna and processed by the receiver. The received radar signal then undergoes pulse compression followed by more mode-specific processing (windshear, weather, ground map, etc.) by the radar processor. During calibration, the radar transmitter generates a similar pulse compression waveform (i.e., calibration pulses), but the calibration pulses bypass the antenna and go directly to the receiver via a “calibration path” built into the hardware. The resulting calibration pulses are used to generate a calibration filter.

Abstract: A method and apparatus for synchronized clocking between a radar receiver and a radar transmitter includes sharing a reference signal between the transmitter and receiver, dividing the common reference into a transmit clock signal in the transmitter and a receive clock signal in the receiver. The receive clock signal and the transmit clock signal are synchronized using a trigger pulse. The synchronization is performed to achieve a 180 degree phase shift between the transmit and receive clocks. Radar pulse transmissions occur on an edge of the transmit clock coinciding with the trigger pulse. A signal recorder is activated on the edge of the receive clock each time the trigger pulse is received. The signal recorder is deactivated after a fixed interval based upon the receiver clock signal.