Abstract: A circuit biases an input transistor by using a voltage on a reference transistor having open gate connection and operating at the same current density as the input transistor to null current leakage at the gate of the input transistor. The input transistor is biased based on the voltage on the zero-gate-current reference transistor. The bias condition for the input transistor to operate at a zero gate current is determined by leaving the gate terminal of the reference transistor open-circuited, thus zero gate current, forcing a desired current through the reference transistor, and measuring a drain-source voltage of the reference transistor. When the input terminal of the input transistor has an ancillary circuitry that may contribute gate leakage current, the same ancillary circuitry can be coupled to the gate of the reference transistor.

Abstract: A delta sigma modulator having: an integrator that receives an input signal; a comparator that outputs a digital pulse when an output of the integrator goes beyond a threshold; a 1 bit DAC that outputs a predetermined analog signal in response to the digital pulse; and a subtractor that subtracts the analog signal from the input signal; wherein the 1-bit DAC comprises: an output MOS transistor having its gate and drain connected by default to a predetermined control voltage and to a current sink; wherein in response to the digital pulse a control circuit controllably brings the MOS transistor to a non-conductive state where any drop in voltage of its source causes the MOS transistor to conduct and, after connecting the drain of the MOS transistor away from the current sink and to an output node, pulls down the source until a predetermined charge is sent to the output node.

Abstract: An auto-zeroed charge transfer circuit uses an output MOS transistor having a gate, a source and a drain; the gate of the MOS transistor being maintained to a predetermined control voltage and the drain of the MOS transistor being connected by default to a current sink; and a control circuit arranged to, in response to an input signal, bring the MOS transistor to a non-conductive state where any drop in voltage of the MOS transistor source causes the MOS transistor to conduct and, after connecting the drain of the MOS transistor away from the current sink and to an output node, pull down the source of the MOS transistor until a predetermined charge is sent to the output node through the MOS transistor.

Abstract: A cellular radio architecture that includes a programmable bandpass sampling radio frequency front-end and an optimized digital baseband. The architecture includes a receiver module having a plurality of signal channels for different frequency bands, where each signal channel in the receiver module includes a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The architecture also includes a transmitter module having a transmitter delta-sigma modulator for converting digital data bits to analog transmit signals, where the transmitter module includes a power amplifier and a switch for directing the transmit signals to one of the signal paths. The architecture also includes a dual self-cancellation circuit providing digital and analog cancellation of the transmit signal in the receiver module.

Abstract: A cellular radio architecture that includes a multiplexer coupled to an antenna structure and including multiple signal paths, where each signal path includes a bandpass filter that passes a different frequency band than the other bandpass filters and a circulator that provides signal isolation between the transmit signals and the receive signals. The architecture also includes a receiver module having a separate signal channel for each of the signal paths in the multiplexer, where each signal channel in the receiver module includes a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The delta-sigma modulator includes an LC filter having a plurality of LC resonator circuits, a plurality of transconductance amplifiers and a plurality of integrator circuits, where a combination of one resonator circuit, transconductance amplifier and integrator circuit represents a two-order stage of the LC filter.

Abstract: A cellular radio architecture for a vehicle that includes a receiver module having a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The architecture further includes a transmitter module having a transmitter delta-sigma modulator for converting digital data bits to analog transmit signals. Portions of the receiver and transmitter modules are fabricated with indium phosphide (InP) technologies and portions of the receiver and transmitter modules are fabricated with CMOS technologies.

Abstract: A cellular radio architecture for a vehicle that includes a triplexer coupled to an antenna structure and including three signal paths, where each signal path includes a bandpass filter that passes a different frequency band than the other bandpass filters and a circulator that provides signal isolation between the transmit signals and the receive signals. The architecture also includes a receiver module having a separate signal channel for each of the signal paths in the triplexer, where each signal channel in the receiver module includes a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The delta-sigma modulator includes an LC filter having a plurality of LC resonator circuits, a plurality of transconductance amplifiers and a plurality of integrator circuits, where a combination of one resonator circuit, transconductance amplifier and integrator circuit represents a two-order stage of the LC filter.

Abstract: An RF transmitter module for a cellular radio that includes a delta-sigma modulator having a plurality of interleaving dynamic element matching (DEM) circuits providing interleaved digital bits at a reduced clock rate. An interleaver controller controls the DEM circuits so as to provide groups of the digital bits at different points in time. In one embodiment, a summation junction adds the groups of the digital bits to provide a continuous stream of the interleaved digital bits, a DAC converts the stream of interleaved digital bits to an analog signal, and a power amplifier amplifies the analog signal.

Abstract: A cellular radio architecture for a vehicle that includes a programmable bandpass sampling radio frequency front-end and an optimized digital baseband. The architecture includes a triplexer having signal paths that include a bandpass filter that passes a different frequency band than the other bandpass filters and a circulator that provides signal isolation between the transmit signals and the receive signals. The architecture also includes a receiver module having a separate signal channel for each of the signal paths in the triplexer, where each signal channel in the receiver module includes a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The architecture further includes a transmitter module having a transmitter delta-sigma modulator for converting digital data bits to analog transmit signals, where the transmitter module includes a power amplifier and a switch for directing the transmit signals to one of the signal paths in the triplexer.

Abstract: A cellular radio architecture that includes a receiver module having a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The architecture further includes a transmitter module having a transmitter delta-sigma modulator for converting digital data bits to analog transmit signals. Portions of the receiver and transmitter modules are fabricated with silicon germanium (SiGe) technologies and portions of the receiver and transmitter modules are fabricated with CMOS technologies.

Abstract: A transceiver front-end circuit for a cellular radio architecture for a vehicle, where the transceiver circuit employs components for reducing power consumption. The transceiver circuit includes a receiver module having a delta-sigma modulator that converts analog receive signals to a representative digital signal in an interleaving process, where the delta-sigma modulator includes a combiner, a low noise amplifier (LNA), an LC filter and a quantizer circuit. The LC filter is a multi-order filter and the quantizer circuit is an interleaving quantizer circuit that interleaves multiple groups of bits from the filter. The order of the LC filter is selectively reduced in situations where a full dynamic range of the cellular radio is not required and a bit resolution of the quantizer circuit is reduced so as to reduce the power requirements of the cellular radio.

Abstract: A method for reducing power consumption in a transceiver front-end circuit for a cellular radio. The transceiver circuit includes a receiver module having a delta-sigma modulator that converts analog receive signals to a representative digital signal in an interleaving process, where the delta-sigma modulator includes a combiner, a low noise amplifier (LNA), an LC filter and a quantizer circuit. The LC filter is a multi-order filter and the quantizer circuit is an interleaving quantizer circuit that interleaves multiple groups of bits from the filter. The method includes selectively reducing the order of the LC filter in situations where a full dynamic range of the cellular radio is not required and reducing a bit resolution of the quantizer circuit so as to reduce the power requirements of the cellular radio.

Abstract: A method for reducing power consumption in a transceiver front-end circuit for a cellular radio. The transceiver circuit includes a receiver module having a delta-sigma modulator that converts analog receive signals to a representative digital signal in an interleaving process, where the delta-sigma modulator includes a low noise amplifier (LNA), an LC filter and a quantizer circuit. The LC filter is a multi-order filter and the quantizer circuit is an interleaving quantizer circuit that interleaves multiple groups of bits from the filter. The method includes selectively reducing the order of the LC filter in situations where a full dynamic range of the cellular radio is not required and reducing a bit resolution of the quantizer circuit so as to reduce the power requirements of the cellular radio.

Abstract: A cellular radio architecture that includes a programmable bandpass sampling radio frequency front-end and an optimized digital baseband. The architecture includes a multiplexer having signal paths that include a bandpass filter that passes a different frequency band than the other bandpass filters and a circulator that provides signal isolation between the transmit signals and the receive signals. The architecture also includes a receiver module having a separate signal channel for each of the signal paths in the multiplexer, where each signal channel in the receiver module includes a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The architecture further includes a transmitter module having a transmitter delta-sigma modulator for converting digital data bits to analog transmit signals, where the transmitter module includes a power amplifier and a switch for directing the transmit signals to one of the signal paths in the multiplexer.

Abstract: An RF transmitter module for a cellular radio that includes a delta-sigma modulator having a plurality of interleaving dynamic element matching (DEM) circuits providing interleaved digital bits at a reduced clock rate. An interleaver controller controls the DEM circuits so as to provide groups of the digital bits at different points in time. In one embodiment, a summation junction adds the groups of the digital bits to provide a continuous stream of the interleaved digital bits, a DAC converts the stream of interleaved digital bits to an analog signal, and a power amplifier amplifies the analog signal.

Abstract: A transceiver front-end circuit for a cellular radio architecture for a vehicle, where the transceiver circuit employs components for reducing power consumption. The transceiver circuit includes a receiver module having a delta-sigma modulator that converts analog receive signals to a representative digital signal in an interleaving process, where the delta-sigma modulator includes a combiner, a low noise amplifier (LNA), an LC filter and a quantizer circuit. The LC filter is a multi-order filter and the quantizer circuit is an interleaving quantizer circuit that interleaves multiple groups of bits from the filter. The order of the LC filter is selectively reduced in situations where a full dynamic range of the cellular radio is not required and a bit resolution of the quantizer circuit is reduced so as to reduce the power requirements of the cellular radio.

Abstract: A method for reducing power consumption in a transceiver front-end circuit for a cellular radio. The transceiver circuit includes a receiver module having a delta-sigma modulator that converts analog receive signals to a representative digital signal in an interleaving process, where the delta-sigma modulator includes a low noise amplifier (LNA), an LC filter and a quantizer circuit. The LC filter is a multi-order filter and the quantizer circuit is an interleaving quantizer circuit that interleaves multiple groups of bits from the filter. The method includes selectively reducing the order of the LC filter in situations where a full dynamic range of the cellular radio is not required and reducing a bit resolution of the quantizer circuit so as to reduce the power requirements of the cellular radio.

Abstract: A cellular radio architecture that includes a receiver module having a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The architecture further includes a transmitter module having a transmitter delta-sigma modulator for converting digital data bits to analog transmit signals. Portions of the receiver and transmitter modules are fabricated with silicon germanium (SiGe) technologies and portions of the receiver and transmitter modules are fabricated with CMOS technologies.

Abstract: A cellular radio architecture that includes a multiplexer coupled to an antenna structure and including multiple signal paths, where each signal path includes a bandpass filter that passes a different frequency band than the other bandpass filters and a circulator that provides signal isolation between the transmit signals and the receive signals. The architecture also includes a receiver module having a separate signal channel for each of the signal paths in the multiplexer, where each signal channel in the receiver module includes a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The delta-sigma modulator includes an LC filter having a plurality of LC resonator circuits, a plurality of transconductance amplifiers and a plurality of integrator circuits, where a combination of one resonator circuit, transconductance amplifier and integrator circuit represents a two-order stage of the LC filter.

Abstract: A cellular radio architecture that includes a programmable bandpass sampling radio frequency front-end and an optimized digital baseband. The architecture includes a multiplexer having signal paths that include a bandpass filter that passes a different frequency band than the other bandpass filters and a circulator that provides signal isolation between the transmit signals and the receive signals. The architecture also includes a receiver module having a separate signal channel for each of the signal paths in the multiplexer, where each signal channel in the receiver module includes a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The architecture further includes a transmitter module having a transmitter delta-sigma modulator for converting digital data bits to analog transmit signals, where the transmitter module includes a power amplifier and a switch for directing the transmit signals to one of the signal paths in the multiplexer.