Abstract: In general, one aspect disclosed features an apparatus comprising: an ultra-wideband (UWB) radio configured to transmit a UWB radio signal in a frequency band; a detect circuit configured to monitor the frequency band for the presence of a second radio signal in the frequency band; and a controller configured to cause the UWB radio to transmit the UWB signal responsive to the detect circuit detecting the presence of the second radio signal in the frequency band.

Abstract: Various embodiments leverage the typical manner in which a RAT selects a supported frequency band listed in its acquisition database and the standard communications with its network indicating the supported frequency bands to avoid potential coexistence events with one or more other RATs. In particular, various embodiments include methods for avoiding band interference between RATs operating on a multi-SIM communication device by identifying the frequency bands available to each of the RATs, comparing the identified frequency bands to determine whether any RAT's frequency bands will interfere with one or more other RAT's frequency bands, and in response to determining that there is a possibility of frequency band interference, removing those interfering frequency bands from that RAT's acquisition database. As a result, during standard communications, that RAT will report to its network that it supports only non-interfering frequency bands.

Abstract: This invention uses one or more cancellation modules to eliminate the transmitter leakage at the output of the receive antenna and prior the receiver circuitry so that the received signals can be analyzed without degradation in quality due to simultaneous operation of the transmitter and receiver. Each cancellation circuit could be limited to only 30-50 dB of rejection due to component mismatches and other circuit non-idealities. To obtain further cancellation, more than one cancellation circuit can be applied after the first low noise amplifier. The output of the low noise amplifier can be repeatedly mixed with additional cancellation signals “n” number of times such that the “n” low noise amplifier is mixed with the “nth” cancellation signal. For each additional cancellation signal added a 20-30 dB reduction in noise may be achieved such that cascading three or four cancellation signals from cancellation modules may produce a 150 dB gain.

Abstract: Various aspects of the present disclosure are directed to apparatuses and methods that can mitigate the undesirable effects of residual side band (RSB) signal by actively re-tuning the local oscillator of a transmitter to be at or near the center frequency of the carrier. Other aspects, embodiments, and features are also claimed and described.

Abstract: Various embodiments leverage the typical manner in which a RAT selects a supported frequency band listed in its acquisition database and the standard communications with its network indicating the supported frequency bands to avoid potential coexistence events with one or more other RATs. In particular, various embodiments include methods for avoiding band interference between RATs operating on a multi-SIM communication device by identifying the frequency bands available to each of the RATs, comparing the identified frequency bands to determine whether any RAT's frequency bands will interfere with one or more other RAT's frequency bands, and in response to determining that there is a possibility of frequency band interference, removing those interfering frequency bands from that RAT's acquisition database. As a result, during standard communications, that RAT will report to its network that it supports only non-interfering frequency bands.

Abstract: Methods implemented in a mobile communication device (e.g., a dual-SIM-dual-active or multi-SIM-multi-active communication device) for improving accuracy of radio-frequency (RF) output power measurements include opportunistically scheduling when a power detector takes RF output power measurements of a radio access technology (“RAT”). In various embodiments, a processor of the mobile communication device may ensure that the power detector takes an accurate RF output power measurement of the RAT by identifying an upcoming time window during which the RAT's transmit power is not artificially reduced as a result of performing transmit blanking/zeroing or artificially increased by transmissions originating from one or more other RATs operating on the device, and configuring or scheduling the power detector to take RF output power measurements of the RAT during that upcoming time window. A priority of the measured RAT may be increased in response to repeated delays in obtaining an RF output power measurement.

Abstract: This invention uses one or more cancellation modules to eliminate the transmitter leakage at the output of the receive antenna and prior the receiver circuitry so that the received signals can be analyzed without degradation in quality due to simultaneous operation of the transmitter and receiver. Each cancellation circuit could be limited to only 30-50 dB of rejection due to component mismatches and other circuit non-idealities. To obtain further cancellation, more than one cancellation circuit can be applied after the first low noise amplifier. The output of the low noise amplifier can be repeatedly mixed with additional cancellation signals “n” number of times such that the “n” low noise amplifier is mixed with the “nth” cancellation signal. For each additional cancellation signal added a 20-30 dB reduction in noise may be achieved such that cascading three or four cancellation signals from cancellation modules may produce a 150 dB gain.

Abstract: This invention provides a dual-modality system for performing characterization and imaging of tissue, tumors, structures, lesions, and ablations under investigation. Specifically, the invention couples ultrasound technology comprising at least two focused ultrasound beams for vibrating target tissues located at the focal point of the ultrasound beams intersection with a radio frequency system for measuring the response of the target tissues. The ultrasound system vibrates the target tissues while the reflected radio frequency energy is transmitted into the target tissues. When reflected, the main carrier tone of the reflected radio frequency energy is cancelled and analysis is performed on the remaining sideband frequencies.

Abstract: This invention provides a dual-modality system for performing characterization and imaging of tissue, tumors, structures, lesions, and ablations under investigation. Specifically, the invention couples ultrasound technology comprising at least two focused ultrasound beams for vibrating target tissues located at the focal point of the ultrasound beams intersection with a radio frequency system for measuring the response of the target tissues. The ultrasound system vibrates the target tissues while the reflected radio frequency energy is transmitted into the target tissues. When reflected, the main carrier tone of the reflected radio frequency energy is cancelled and analysis is performed on the remaining sideband frequencies.

Abstract: A frequency multiplier circuit is provided that does not rely on filtering to remove unwanted harmonics and spurious content. In one implementation, a frequency doubler comprises a first rectifier doubler stage adapted to receive a first input signal having a first frequency and output a first rectified signal having multiple harmonics; a second rectifier doubler stage adapted to receive a second input signal having the first frequency and offset in phase from the first input signal and to output a second rectified signal, which has the multiple harmonics and is offset in phase from the first rectified signal; and a differential amplifier stage adapted to sum the first and second rectified signals to produce an output signal including a desired output harmonic having a frequency that is double the first frequency. The summing results in the substantial cancellation of unwanted output harmonics in the output signal.

Abstract: An R-C polyphase network that provides bandpass shaping and amplification to maintain the quadrature phase output is provided. In one implementation, a polyphase device comprises two transistors each having a collector, a base and an emitter. Positive and negative components of an input signal are coupled to a respective base of the transistors, the transistors adapted to drive the R-C polyphase network. Inputs of the R-C polyphase network are coupled to the collectors of the transistors. The R-C polyphase network includes an inductor and has first output and a second output offset in phase. The inductor is adapted to provide bandpass filtering of the first output and the second output to reduce harmonics and spurious content in the output, as well as provide amplification of the outputs relative to the input signal.

Abstract: An R-C polyphase network that provides bandpass shaping and amplification to maintain the quadrature phase output is provided. In one implementation, a polyphase device comprises two transistors each having a collector, a base and an emitter. Positive and negative components of an input signal are coupled to a respective base of the transistors, the transistors adapted to drive the R-C polyphase network. Inputs of the R-C polyphase network are coupled to the collectors of the transistors. The R-C polyphase network includes an inductor and has first output and a second output offset in phase. The inductor is adapted to provide bandpass filtering of the first output and the second output to reduce harmonics and spurious content in the output, as well as provide amplification of the outputs relative to the input signal.

Abstract: A frequency multiplier circuit is provided that does not rely on filtering to remove unwanted harmonics and spurious content. In one implementation, a frequency doubler comprises a first rectifier doubler stage adapted to receive a first input signal having a first frequency and output a first rectified signal having multiple harmonics; a second rectifier doubler stage adapted to receive a second input signal having the first frequency and offset in phase from the first input signal and to output a second rectified signal, which has the multiple harmonics and is offset in phase from the first rectified signal; and a differential amplifier stage adapted to sum the first and second rectified signals to produce an output signal including a desired output harmonic having a frequency that is double the first frequency. The summing results in the substantial cancellation of unwanted output harmonics in the output signal.

Abstract: A power level control circuit for the power amplifier of a mobile cellular unit does not require a matched diode pair yet is simple in design. A sampling device, such as a directional coupler or sampling capacitor, connected to an output of the power amplifier provides a sampled RF signal output. An impedance is connected to the sampling device, and the sampling device forms a RF attenuator. A tunnel diode detector is connected to the sampling device for generating a detected d.c. output signal. Power level control (PLC) circuitry compares the detected d.c. output signal from the tunnel diode detector with a selected power level control reference signal and generates a feedback signal to the RF power amplifier to control the power level output from the amplifier. The dynamic range of this basic circuit is increased by switched attenuators, switched parallel detectors with scaled attenuation factors, or a controlled varactor diode used to change the RF coupling to the diode detector.