Abstract: A system and method for determining a received signal frequency by sampling the received signal at a rate less than twice a predefined nyquist rate. The system includes a distorting component configured to distort the received signal in a frequency dependent manner, at least one analog to digital converter configured to sample the received signal and the distorted signal at a rate less than twice a predefined nyquist rate, and a processing component configured to determine a frequency of the received signal based on the sampled received signal and the sampled distorted signal. The method includes distorting the received signal, sampling the received signal and the distorted signal at a rate less than twice a predefined nyquist rate, and determining a frequency of the received signal. In an embodiment, distorting includes at least one of distorting an amplitude or a group delay of the received signal.

Abstract: A radio receiver is provided that includes a front-end circuit operable to receive radio signals transmitted across a frequency band and generate an analog signal corresponding to a plurality of channels within the frequency band. Also included is an analog to digital converter operable to convert the analog signal to a digital signal, and a digital processing system operable to process the digital signal and simultaneously generate one or more output signals corresponding to at least one of the plurality of channels within the frequency band. Various exemplary embodiments of the radio receiver and associated method are provided.

Abstract: A method of providing visual data to a pilot in an aircraft cockpit includes receiving information in the form of a voice signal, converting the information to visual data, and displaying the visual data to the pilot in the aircraft cockpit.

Abstract: Disclosed is a system and method for compensating for the effects of aging and temperature on the performance of transistors in an RF transmitter. The system and method use a temperature-based polynomial and a feedback control loop to correlate the drain current of each transistor with the desired performance characteristics of each transistor. The present invention measures drain current and temperature of the transistor; compares the measured drain current with the desired drain current, which corresponds to the desired performance characteristics; computes a transistor bias voltage based on the temperature and a control parameter, wherein the control parameter is adjustable based on the measured drain current; and applies the bias voltage to the transistor. The process may be repeated, with the control parameter adjusted with each iteration, until the desired drain current is reached.

Abstract: An audio system may comprise a transceiver configured to receive, detect, and transmit audio signals on a first channel frequency and to receive and detect audio signals on at least one additional channel frequency. The at least one additional channel frequency may include a second channel frequency. The system may include a controller configured to output a first audio cue while outputting audio signals received from the at least one additional channel frequency, to output a second audio cue at a time when the controller begins outputting an audio signal received from the first channel frequency, and to output a third audio cue at a time when the controller begins outputting an audio signal received from the second channel frequency. The first, second, and third audio cues may be different from one another.

Abstract: A radio receiver is provided that includes a front-end circuit operable to receive radio signals transmitted across a frequency band and generate an analog signal corresponding to a plurality of channels within the frequency band. Also included is an analog to digital converter operable to convert the analog signal to a digital signal, and a digital processing system operable to process the digital signal and simultaneously generate one or more output signals corresponding to at least one of the plurality of channels within the frequency band. Various exemplary embodiments of the radio receiver and associated method are provided.

Abstract: Signal processing systems for radar installations are provided for simultaneous processing of one or more IF signals of dynamically varying frequency and bandwidth with a single analog signal path. The signal processing system includes, but is not limited to, a converter configured to digitize a return signal resulting in a digitized broadband signal, and a signal processor coupled to the converter. The signal processor includes a digital filter having a center frequency and a bandwidth, and the digital filter is configured to select a signal from the digitized broadband signal. The selected signal has a center frequency. The signal processor is configured to match the center frequency of the digital filter with the center frequency of the selected signal, and adjust the bandwidth of the digital filter based on the selected signal.

Abstract: A photograph repository system includes data storage for storing photographs in the form of digital data files and a search feature that provides for searching for photographs by location and optionally by other search criteria. In one embodiment, a photograph repository service is accessible to users over a common data network, such as the Internet. In the photograph repository service, each stored photograph is associated with a location, i.e., where the photograph was taken and/or the location of an object in the photograph. Users can search for and obtain copies of their own photographs that they had stored previously with the photograph repository service. In addition, users can search for and obtain copies of photographs that had been taken by other users and stored with the photograph repository service. The photograph repository system can also be implemented as a standalone system, a hybrid system, or a peer-to-peer system.

Abstract: A smearing compensation apparatus for a radar system having a scanning antenna is provided. The apparatus includes a first memory for storing a plurality of data streams, with each data stream corresponds to a radar signal received at a different angular position of the antenna, and a second memory stores radiation pattern data of the antenna. A frequency domain transform processor performs a frequency domain transform on the radiation pattern data stored in the second memory to produce a frequency characteristic of the radiation pattern data. A compensation function processor applies a compensation function to the frequency characteristic of the radiation pattern data to produce a compensated frequency characteristic. An inverse frequency domain transform processor performs an inverse frequency domain transform on the compensated frequency characteristic to produce digital filter coefficients.

Abstract: In a radar system having a transmitter that produces pulses to be radiated by an antenna and a receiver that detects target information, complex demodulation is performed on an attenuated and limited waveform of the transmitter produced pulse. A matched filter is generated responsive to the complex demodulated waveform that is a time reversed conjugate image of the waveform corresponding to the produced pulse. Complex demodulation is performed on the return signal received by the receiver corresponding the produced pulse and the complex demodulated return signal is correlated with the matched filter that corresponds to the time reversed conjugate image of the waveform of the produced pulse.