An integrated analog to digital converting and digital to analog converting (ADDA) RF transceiver for satellite applications, configured to replace conventional analog RF down and up conversion circuitry. The ADDA RF transceiver includes one of more ADCs, DSPs, and DACs, all on a single ASIC. Further, the circuitry is to be radiation tolerant for high availability and reliability in the ionizing radiation environment present in the space environment.

A millimeter-wave phase array system may include massive heterodyne transceivers as its building elements. A transceiver of each element may include an IQ image rejection heterodyne transmitter and a receiver. Each transmitter may include a single DAC, a Tx I channel, and a Tx Q channel. Each receiver may include an Rx I channel, an Rx Q channel, and a single ADC. For Tx IQ image rejection calibration, amplitude and phase offsets are determined, using both the Tx I and Tx Q channels from a first element and using only one of the Rx I or Rx Q channel from a second element. The IQ channel imbalances are compensated using the offsets in analog domain. A similar procedure is used for Rx IQ image rejection calibration with alternated signal path enabling. A frequency response variation of an RF front end is detected with a single path Tx/Rx channel setup.

In some implementations, a communication device, includes a printed circuit board comprising conductors routed to support a plurality of different configurations of modulation and/or demodulation functionality. The printed circuit board can have multiple analog output interfaces and one or more analog input interfaces, multiple digital network interfaces, and sockets for components including a controller, multiple processors, digital-to-analog converters (DACs), and an analog-to-digital converter (ADC). Various processor sockets are interconnected to support the processors in different sockets selectively being used for different functions, e.g., as a modulator, burst processor, channelizer, etc.

A wideband receiver system comprises a wideband analog-to-digital converter (ADC) module and a digital frontend (DFE) module. The wideband ADC is configured to concurrently digitize a band of frequencies comprising a plurality of desired channels and a plurality of undesired channels. The DFE module is coupled to the digital in-phase and quadrature signals. The DFE module is configured to select the plurality of desired channels from the digitized band of frequencies, and generate an intermediate frequency (IF) signal comprising the selected plurality of desired channels and having a bandwidth that is less than a bandwidth of the band of frequencies, where the generation comprises frequency shifting of the selected plurality of desired channels. The IF signal may be a digital signal and the DFE is configured to output the IF signal via a serial or parallel interface.

According to the present disclosure, there is provided a signal generation apparatus including: a base band module (11); a DA converter that converts digital base band signals into modulation signals corresponding to a plurality of cells; an RF converter (20) to which the modulation signals corresponding to the plurality of cells are input, and which outputs an RF signal obtained by frequency-converting the modulation signal; and an RF converter control unit (31), in which the RF converter control unit controls the base band module to reduce a power value of a digital base band signal corresponding to a predetermined cell, among the digital base band signals corresponding to the plurality of cells in the base band module so that an input level of the modulation signal input to the RF converter is equal to or lower than an input limit value of the RF converter.

Apparatus and methods remove a voltage offset from an electrical signal, specifically a biomedical signal. A signal is received at a first operational amplifier and is amplified by a gain. An amplitude of the signal is monitored, by a first pair of diode stages coupled to an output of the first operational amplifier, for the voltage offset. The amplitude of the signal is then attenuated by the first pair of diode stages and a plurality of timing banks. The attenuating includes limiting charging, by the first pair of diode stages, of the plurality of timing banks and setting a time constant based on the charging. The attenuating removes the voltage offset persisting at a threshold for a duration of at least the time constant. Saturation of the signal is limited to a saturation recovery time while the saturated signal is gradually pulled into monitoring range over the saturation recovery time.

Apparatus and methods remove a voltage offset from an electrical signal, specifically a biomedical signal. A signal is received at a first operational amplifier and is amplified by a gain. An amplitude of the signal is monitored, by a first pair of diode stages coupled to an output of the first operational amplifier, for the voltage offset. The amplitude of the signal is then attenuated by the first pair of diode stages and a plurality of timing banks. The attenuating includes limiting charging, by the first pair of diode stages, of the plurality of timing banks and setting a time constant based on the charging. The attenuating removes the voltage offset persisting at a threshold for a duration of at least the time constant. Saturation of the signal is limited to a saturation recovery time while the saturated signal is gradually pulled into monitoring range over the saturation recovery time.

A wideband receiver system comprises a wideband analog-to-digital converter (ADC) module and a digital frontend (DFE) module. The wideband ADC is configured to concurrently digitize a band of frequencies comprising a plurality of desired channels and a plurality of undesired channels. The DFE module is coupled to the digital in-phase and quadrature signals. The DFE module is configured to select the plurality of desired channels from the digitized band of frequencies, and generate an intermediate frequency (IF) signal comprising the selected plurality of desired channels and having a bandwidth that is less than a bandwidth of the band of frequencies, where the generation comprises frequency shifting of the selected plurality of desired channels. The IF signal may be a digital signal and the DFE is configured to output the IF signal via a serial or parallel interface.

A method of switching between noise reduction modes in multi-microphone mobile devices may include receiving a first sound signal at a first sound receiver and receiving a second sound signal at a second sound receiver. The method may also include determining a first power value associated with the first sound signal and determining a second power value associated with the second sound signal. The method may additionally include comparing the first power value to the second power value and switching between a single-microphone noise reduction mode and a dual-microphone noise reduction mode based on the comparison.

A radio frequency (RF) transceiver system comprises an input port configured to receive an RF receive signal and a receiver (RX) digital signal processing (DSP) unit configured to process a digital IF signal based on the RF receive signal and generate a processed digital IF signal at an output port based thereon. Further, the RF transceiver system comprises a digital interface unit comprising a digital interface configured to convey the processed digital IF signal from the output port. In addition, the RF transceiver system comprises a quality estimation unit configured to estimate a quality indicator of the RF receive signal or a signal associated therewith, and dynamically adapt a digital transmission word length of the processed digital IF signal over the digital interface, based on the estimated quality indicator.