摘要:
A direct broadcast satellite (DBS) reception assembly may comprise an integrated circuit that is configurable between or among a plurality of configurations based on content requested by client devices served by the DBS reception assembly. In a first configuration, multiple satellite frequency bands may be digitized by the integrated circuit as a single wideband signal. In a second configuration, the satellite frequency bands may be digitized by the integrated circuit as a plurality of separate narrowband signals. The integrated circuit may comprise a plurality of receive paths, each of the receive chains comprising a respective one of a plurality of low noise amplifiers and a plurality of analog-to-digital converters.
摘要:
A system for processing signals may be configured to apply digital conversion to analog signals, and to apply, prior to the analog-to-digital conversion, a gain to at least a portion of the analog signals. The gain may be controlled and/or adjusted based on processing of digital output generated based on the analog-to-digital conversion. The system may comprise a plurality of sampling slices, which may be configured to provide the analog-to-digital conversion in interleaved (e.g., time-interleaved) manner. Each of the sampling slices may comprise a dedicated gain element, for applying gain to signals handled by the corresponding slice. The gain applied by the gain elements of the sampling slices may be controlled, independently, collectively, and/or in based on grouping into subsets. The gain may be controlled based on application of a particular gain control algorithm, which may be selected from a plurality of predefined algorithms.
摘要:
Methods and systems for a baseband cross-bar may comprise receiving one or more radio frequency (RF) signals in a wireless communication device via antennas coupled to a plurality of receiver paths in the wireless device. The received RF signals may be converted to baseband frequencies. One or more of the down-converted signals may be coupled to receiver paths utilizing a baseband cross-bar. The baseband cross-bar may comprise a plurality of switches, which may comprise CMOS transistors. In-phase and quadrature signals may be processed in the one or more of the plurality of receiver paths. The one or more RF signals comprise cellular signals and/or global navigation satellite signals. A single-ended received RF signal may be converted to a differential signal in one or more of the plurality of receiver paths. The baseband cross-bar may be controlled utilizing a reduced instruction set computing (RISC) processor.
摘要:
A downconverter is provided. The downconverter includes a I mixer and a Q mixer. Each mixer includes a transconductance stage and a mixer core stage. The outputs of the transconductance stages of the mixers are shorted together, and a resistors are arranged in series with an input of the mixer core stages.
摘要:
Methods and systems for improved cross polarization rejection and tolerating of coupling between satellite signals may comprise receiving radio frequency (RF) signals on a chip, where the RF signals comprising a desired signal and at least one crosstalk signal. The received RF signals may be down-converted to baseband frequencies, and the down-converted signals are converted to digital signals. Crosstalk may be determined by estimating complex coupling coefficients between the received RF signals utilizing a de-correlation algorithm across a frequency bandwidth comprising the desired and crosstalk signals. The down-converted signals may be low-pass filtered and summed with an output signal from a cancellation filter. The complex coupling coefficients may be determined utilizing the de-correlation algorithm on the summed signals, and may be used to configure the cancellation filter. Crosstalk may be canceled in a receiver path from a cancellation filter receiving low-pass filtered down-converted signals from another path.
摘要:
Methods and systems for a baseband cross-bar may comprise receiving one or more radio frequency (RF) signals in a wireless communication device via antennas coupled to a plurality of receiver paths in the wireless device. The received RF signals may be converted to baseband frequencies. One or more of the down-converted signals may be coupled to receiver paths utilizing a baseband cross-bar. The baseband cross-bar may comprise a plurality of switches, which may comprise CMOS transistors. In-phase and quadrature signals may be processed in the one or more of the plurality of receiver paths. The one or more RF signals comprise cellular signals and/or global navigation satellite signals. A single-ended received RF signal may be converted to a differential signal in one or more of the plurality of receiver paths. The baseband cross-bar may be controlled utilizing a reduced instruction set computing (RISC) processor.
摘要:
A circuit for down-converting an RF signal to a baseband signal includes a trans-admittance amplifier adapted to receive the RF signal and generate in response a pair of differential current signals. The circuit further includes a trans-impedance amplifier having at least four mixers and at least four linear amplifiers. The four mixers frequency down-convert the pair of differential current signals to generate four pairs of differential baseband current signals, wherein each pair of the differential baseband current signals has a different phase and is associated with each of the linear amplifiers. Additionally, the circuit includes a summing block that generates an in-phase signal using a first weighted sum of the four different baseband current signals and a quadrature signal using a second weighted sum of the four different baseband current signals. The circuit further includes an analog-to-digital converter for converting the in-phase and quadrature signals to respective digital representations.
摘要:
Methods and systems for improved cross polarization rejection and tolerating of coupling between satellite signals may comprise receiving radio frequency (RF) signals on a chip, where the RF signals comprising a desired signal and at least one crosstalk signal. The received RF signals may be down-converted to baseband frequencies, and the down-converted signals are converted to digital signals. Crosstalk may be determined by estimating complex coupling coefficients between the received RF signals utilizing a de-correlation algorithm across a frequency bandwidth comprising the desired and crosstalk signals. The down-converted signals may be low-pass filtered and summed with an output signal from a cancellation filter. The complex coupling coefficients may be determined utilizing the de-correlation algorithm on the summed signals, and may be used to configure the cancellation filter. Crosstalk may be canceled in a receiver path from a cancellation filter receiving low-pass filtered down-converted signals from another path.
摘要:
A harmonic rejection mixer includes a first scaling circuit for scaling an RF signal to generate a plurality of scaled RF signals, a first switching stage for sampling the scaled RF signals using a first plurality of switching signals, and a second mixing stage for mixing the sampled RF signals with a second plurality of switching signals to generate a plurality of frequency translated signals having different phases. A combiner adds the frequency translated signals together to generate a first plurality of baseband versions of the RF signal. A first amplifier stage processes the first plurality of baseband versions to generate a second plurality of baseband versions. The mixer further includes a second scaling circuit for scaling the second plurality of baseband versions and a second amplifier stage to generate an in-phase baseband signal and a quadrature baseband signal from the scaled second plurality of baseband versions.
摘要:
A circuit for down-converting an RF signal to a baseband signal includes a trans-admittance amplifier adapted to receive the RF signal and generate in response a pair of differential current signals. The circuit further includes a trans-impedance amplifier having at least four mixers and at least four linear amplifiers. The four mixers frequency down-convert the pair of differential current signals to generate four pairs of differential baseband current signals, wherein each pair of the differential baseband current signals has a different phase and is associated with each of the linear amplifiers. Additionally, the circuit includes a summing block that generates an in-phase signal using a first weighted sum of the four different baseband current signals and a quadrature signal using a second weighted sum of the four different baseband current signals. The circuit further includes an analog-to-digital converter for converting the in-phase and quadrature signals to respective digital representations.