Abstract: A Cartesian loop circuit includes a reference signal amplifier, a forward path coupled to the reference signal amplifier, a feedback path coupled to the forward path, and a controller. The forward path includes an up-mixer to up mix a forward path signal to a radio frequency signal. The feedback path includes a down-mixer to down mix a feedback signal to a frequency of a baseband reference signal inputted to the forward path. The feedback path provides the down-mixed feedback signal to the forward path. The controller is to perform power control at a low power by controlling a gain of the reference signal amplifier and is to perform power control at a high power by controlling a gain of the down-mixer. At the high power, the controller may perform power control by further controlling the gain of the up-mixer.

Abstract: A Cartesian loop circuit includes a reference signal amplifier, a forward path coupled to the reference signal amplifier, a feedback path coupled to the forward path, and a controller. The forward path includes an up-mixer to up mix a forward path signal to a radio frequency signal. The feedback path includes a down-mixer to down mix a feedback signal to a frequency of a baseband reference signal inputted to the forward path. The feedback path provides the down-mixed feedback signal to the forward path. The controller is to perform power control at a low power by controlling a gain of the reference signal amplifier and is to perform power control at a high power by controlling a gain of the down-mixer. At the high power, the controller may perform power control by further controlling the gain of the up-mixer.

Abstract: A Cartesian loop circuit includes a reference signal amplifier, a forward path coupled to the reference signal amplifier, a feedback path coupled to the forward path, and a controller. The forward path includes an up-mixer to up mix a forward path signal to a radio frequency signal. The feedback path includes a down-mixer to down mix a feedback signal to a frequency of a baseband reference signal inputted to the forward path. The feedback path provides the down-mixed feedback signal to the forward path. The controller is to perform power control at a low power by controlling a gain of the reference signal amplifier and is to perform power control at a high power by controlling a gain of the down-mixer. At the high power, the controller may perform power control by further controlling the gain of the up-mixer.

Abstract: A scalable dynamic range analog-to-digital converter. In one instance, a method of scaling a dynamic range of an analog-to-digital converter is provided. The method includes operating the analog-to-digital converter at a first dynamic range. The method also includes receiving a radio frequency signal and detecting an on-channel signal level of the radio frequency signal. The method also includes when the on-channel signal level is above an on-channel threshold, operating the analog-to-digital converter at a second dynamic range. The method also includes when the on-channel signal level is below the on-channel threshold, operating the analog-to-digital converter at the first dynamic range.

Abstract: A scalable dynamic range analog-to-digital converter. In one instance, a method of scaling a dynamic range of an analog-to-digital converter is provided. The method includes operating the analog-to-digital converter at a first dynamic range. The method also includes receiving a radio frequency signal and detecting an on-channel signal level of the radio frequency signal. The method also includes when the on-channel signal level is above an on-channel threshold, operating the analog-to-digital converter at a second dynamic range. The method also includes when the on-channel signal level is below the on-channel threshold, operating the analog-to-digital converter at the first dynamic range.

Abstract: A method and apparatus for a method and apparatus for correlation canceller for interference mitigation with adaptive DC offset cancellation for a dual mode communication device includes detecting an active signal transmitting in one mode; configuring integrators associated with the adaptive correlation canceller into gain amplifiers; detecting DC offset utilizing the gain amplifiers and comparators; and configuring the integrators from the gain amplifiers back to integrators with the DC offset applied thereto. The active signal transmitting in one mode can be Long Term Evolution (LTE) which is adjacent to a signal in another mode.

Abstract: A method and apparatus for a method and apparatus for correlation canceller for interference mitigation with adaptive DC offset cancellation for a dual mode communication device includes detecting an active signal transmitting in one mode; configuring integrators associated with the adaptive correlation canceller into gain amplifiers; detecting DC offset utilizing the gain amplifiers and comparators; and configuring the integrators from the gain amplifiers back to integrators with the DC offset applied thereto. The active signal transmitting in one mode can be Long Term Evolution (LTE) which is adjacent to a signal in another mode.

Abstract: A method and apparatus is provided for mitigating multiband self-interference using multipath cancellation. A dual-band transceiver receives an incoming radio-frequency signal that includes a multipath self-interference component generated by the transmission of an outgoing radio-frequency signal. The transceiver creates a plurality of reference signals from the outgoing radio-frequency signal by introducing delay values with respect to the outgoing signal. The transceiver adjusts the amplitude and phase of each of the delayed reference signals and combines the resulting signals with the incoming radio-frequency signal to cancel the self-interference component. The delay values may be determined adaptively. The systems and methods described herein are particularly useful for dual-band transceivers capable of communicating simultaneously using Long-Term Evolution (LTE) wideband signals and Public-Safety Narrowband (PSNB) signals.

Abstract: A method and apparatus is provided for mitigating multiband self-interference using multipath cancellation. A dual-band transceiver receives an incoming radio-frequency signal that includes a multipath self-interference component generated by the transmission of an outgoing radio-frequency signal. The transceiver creates a plurality of reference signals from the outgoing radio-frequency signal by introducing delay values with respect to the outgoing signal. The transceiver adjusts the amplitude and phase of each of the delayed reference signals and combines the resulting signals with the incoming radio-frequency signal to cancel the self-interference component. The delay values may be determined adaptively. The systems and methods described herein are particularly useful for dual-band transceivers capable of communicating simultaneously using Long-Term Evolution (LTE) wideband signals and Public-Safety Narrowband (PSNB) signals.

Abstract: A wireless receiver (100) for receiving and demodulating a frequency modulated RF (radio frequency) signal by a direct conversion procedure, including channels (110, 112) for producing in-phase and quadrature components of a received RF signal, and a processor (123, 133) for periodically estimating an error in at least one of the in-phase and quadrature phase components and for producing a signal for adjustment of at least one of the in-phase and quadrature components to compensate for the detected error, wherein the processor is operable to apply alternatively each of a plurality of different procedures to estimate the error, the procedures including a first procedure which is applied when a signal quality value of the received RF signal is above a threshold value and a second procedure which is applied when a signal quality value of the RF received signal is not above the threshold value.

Abstract: A wireless receiver (100) for receiving and demodulating a frequency modulated RF (radio frequency) signal by a direct conversion procedure, including channels (110, 112) for producing in-phase and quadrature components of a received RF signal, and a processor (123, 133) for periodically estimating an error in at least one of the in-phase and quadrature phase components and for producing a signal for adjustment of at least one of the in-phase and quadrature components to compensate for the detected error, wherein the processor is operable to apply alternatively each of a plurality of different procedures to estimate the error, the procedures including a first procedure which is applied when a signal quality value of the received RF signal is above a threshold value and a second procedure which is applied when a signal quality value of the RF received signal is not above the threshold value.

Abstract: A wireless communication unit (100) comprises a voltage controlled oscillator (123) having an active device (450) operably coupled to a first variable capacitance (425) to provide a variable capacitance value based on an applied steering line voltage, and a feedback network comprising a resonator (475), operably coupled to an output of the active device, for feeding power back to an input of the active device to sustain oscillations (123). Notably, a second variable capacitance is operably coupled to receive a control voltage from the steering line (405) and located between the resonator (475) and the active device (450).

Abstract: A wireless communication unit (100) comprises a voltage controlled oscillator (123) having an active device (450) operably coupled to a first variable capacitance (425) to provide a variable capacitance value based on an applied steering line voltage, and a feedback network comprising a resonator (475), operably coupled to an output of the active device, for feeding power back to an input of the active device to sustain oscillations (123). Notably, a second variable capacitance is operably coupled to receive a control voltage from the steering line (405) and located between the resonator (475) and the active device (450).

Abstract: A wireless communication unit (400) comprises a dual-port modulator for generating a radio frequency signal. A digital to analogue converter (446), operably coupled to a data generator (570), converts digital data to an analogue signal to be used in generating the radio frequency signal. An attenuator (450), operably coupled to the digital to analogue converter (446) attenuates the analogue signal output from the digital to analogue converter (446). A signal processor (402) is operably coupled to the attenuator (450) for setting an attenuation value of the attenuator (450) to balance signals input to the two ports of the dual-port modulator.