Abstract: Systems and methods are provided for adjusting a noise figure in a radio receiver. An example method includes receiving a radio frequency (RF) signal at a RF receiver section. The RF receiver section includes at least one RF receiver element. The RF receiver element is controllable by at least one tuning variable. The RF signal is processed to generate a processed analog signal, which is converted to a digital signal. The digital signal is used to determine a performance parameter. The at least one tuning variable of the at least one RF receiver element is controlled to adjust the noise figure based on the performance parameter. In another aspect of the invention, an example radio receiver is provided. The radio receiver includes a RF receiver section having at least one RF receiver element. A controller determines a performance parameter using the digital signal and controls the at least one tuning variable to adjust the noise figure based on the performance parameter.

Abstract: In a system and method for simultaneously receiving or switching between dual frequency carrier signals in a GPS receiver, the GPS receiver is adapted to utilize different harmonics of a sub-harmonic frequency generator, which may include a lower frequency voltage controlled oscillator (VCO) to detect the L1 and L2 GPS carriers. A sub-harmonic mixer may be used to simultaneously down convert the L1 and L2 signals to a lower intermediate frequency (IF). A second mixer may be an image reject (IR) mixer used to separate the downconverted L1 and L2 signals. This mixer may be configured to simultaneously monitor the L1 and L2 signals, or to switch between the L1 and L2 signals. High frequency switching is not required of the radio frequency (RF) input or local oscillator signals, and simultaneous L1 and L2 reception is enabled without and 3 dB image noise degradation.

Abstract: Systems and methods are provided for adjusting a noise figure in a radio receiver. An example method includes receiving a radio frequency (RF) signal at a RF receiver section. The RF receiver section includes at least one RF receiver element. The RF receiver element is controllable by at least one tuning variable. The RF signal is processed to generate a processed analog signal, which is converted to a digital signal. The digital signal is used to determine a performance parameter. The at least one tuning variable of the at least one RF receiver element is controlled to adjust the noise figure based on the performance parameter. In another aspect of the invention, an example radio receiver is provided. The radio receiver includes a RF receiver section having at least one RF receiver element. A controller determines a performance parameter using the digital signal and controls the at least one tuning variable to adjust the noise figure based on the performance parameter.

Abstract: A reconfigurable downconverter (10) for a multi-band positioning receiver is operable with an RF synthesizer (18) with fixed output frequency, and a fixed wideband RF input (28). The downconverter (10) includes an RF mixer (12) operable to accept a range of frequencies that encompass the GPS and Galileo frequency bands and to output a downconverted IF signal (32). A fixed frequency local oscillator signal (34) is coupled to the RF mixer (12). At least one IF processor 14 further downconverts the downconverted IF signal (32) to at least one baseband signal (22). At least one of the IF processors (14) is reconfigurable for different frequency bands.

Abstract: In a system and method for simultaneously receiving or switching between dual frequency carrier signals in a GPS receiver, the GPS receiver is adapted to utilize different harmonics of a sub-harmonic frequency generator, which may include a lower frequency voltage controlled oscillator (VCO) to detect the L1 and L2 GPS carriers. A sub-harmonic mixer may be used to simultaneously down convert the L1 and L2 signals to a lower intermediate frequency (IF). A second mixer may be an image reject (IR) mixer used to separate the downconverted L1 and L2 signals. This mixer may be configured to simultaneously monitor the L1 and L2 signals, or to switch between the L1 and L2 signals. High frequency switching is not required of the radio frequency (RF) input or local oscillator signals, and simultaneous L1 and L2 reception is enabled without a 3 dB image noise degradation.

Abstract: In a system and method for simultaneously receiving or switching between dual frequency carrier signals in a GPS receiver, the GPS receiver is adapted to utilize different harmonics of a sub-harmonic frequency generator, which may include a lower frequency voltage controlled oscillator (VCO) to detect the L1 and L2 GPS carriers. A sub-harmonic mixer may be used to simultaneously down convert the L1 and L2 signals to a lower intermediate frequency (IF). A second mixer may be an image reject (IR) mixer used to separate the downconverted L1 and L2 signals. This mixer may be configured to simultaneously monitor the L1 and L2 signals, or to switch between the L1 and L2 signals. High frequency switching is not required of the radio frequency (RF) input or local oscillator signals, and simultaneous L1 and L2 reception is enabled without a 3dB image noise degradation.

Abstract: In a system and method for simultaneously receiving or switching between dual frequency carrier signals in a GPS receiver is adapted to utilize different harmonics of a sub-harmonic frequency generator, which may include a lower frequency voltage controlled oscillator (VCO) to detect the L1 and L2 GPS carriers. A sub-harmonic mixer may be used to simultaneously down convert the L1 and L2 signals to a lower intermediate frequency (IF). A second mixer may be an image reject (IR) mixer used to separate the downconverted second L2 signals. This mixer may be configured to simultaneously monitor the L1 and L2 signals, or to switch between the L1 and L2 signals. High frequency switching is not required of the radio frequency (RF) input or local oscillator signals, and simultaneous L1 and L2 reception is enabled without a 3 dB image noise degradation. This method minimizes the RF components and power dissipation in a dual frequency GPS receiver, while optimizing the functionality and performance.

Abstract: A digital optical receiver and clock recovery circuit for use in detecting and retiming optical data transmitted at rates up to and exceeding 40 Gb/s. The receiver is made, in part, of superconducting Josephson junctions. The receiver includes an optical signal detector, an SFQ (single flux quantum) transition detector for converting the signal from the photodetector into a stream of single flux quantum signals, and a clock recovery circuit. The clock recovery circuit includes a superconducting ring oscillator in which an SFQ pulse rotates and provides a clock signal at an output of the oscillator. When a pulse from the stream of single flux quantum pulses arrives from the transition detector, two pulses are generated in the ring oscillator. One of the pulses eliminates the rotating SFQ pulse and the second pulse replaces the rotating SFQ pulse, thereby recovering the phase of the clock signal in one bit.