Abstract: Components of a radio-frequency (RF) apparatus including transceiver circuitry and frequency modification circuitry of a crystal oscillator circuit that generates a reference signal with adjustable frequency may be partitioned in a variety of ways, for example, as one or more separate integrated circuits. The frequency modification circuitry may be implemented as part of a crystal oscillator circuit that includes digitally controlled crystal oscillator (“DCXO”) circuitry and a crystal. The frequency modification circuitry may include at least one variable capacitance device and may be employed to generate a reference signal with adjustable frequency. The adjustable reference signal may be provided to other components of the RF apparatus and/or the RF apparatus may be configured to provide the adjustable reference signal to baseband processor circuitry.

Abstract: A mobile communications system comprising a phase-locked loop (PLL), radio frequency (RF) circuitry, and control circuitry configured to activate the PLL and the RF circuitry during a plurality of substantially mutually exclusive time intervals is provided.

Abstract: A communication apparatus includes a radio frequency circuit that operates on a radio frequency signal and a digital processing circuit coupled to the radio frequency circuit. The digital processing circuit includes a plurality of bus masters coupled to a shared bus. A bus arbiter is provided for arbitrating between requests to access the bus by a first bus master and one or more other bus masters. Accesses by the one or more other bus masters to the bus are restricted in response to a signal indicative of a change in a mode of operation of the RF circuit. In one particular implementation, a communication apparatus employs time domain isolation wherein the digital processing circuit may be placed in a shutdown mode when the radio frequency circuit is active.

Abstract: A radio-frequency (RF) receiver includes a receiver analog circuitry and a receiver digital circuitry. The receiver analog circuitry resides within a first integrated circuit and the receiver digital circuitry resides within a second integrated circuit. The second integrated circuit couples to the first integrated circuit via a one-bit digital interface. The receiver analog circuitry receives an RF signal and processes the received RF signal to generate a digital signal. The receiver analog circuitry provides the digital signal to the receiver digital circuitry. The receiver digital circuitry includes a digital down-converter circuitry that mixes the digital signal with an intermediate frequency (IF) local oscillator (LO) signal to generate a digital down-converted signal. The receiver digital circuitry also includes a digital filter circuitry that filters the digital down-converted signal to generate a filtered digital signal.

Abstract: A method is disclosed for performing dual mode image rejection calibration in a receiver. A first image correction factor is acquired (1302) for use in a receiver system (15) using a first known signal associated with a first signal band during a startup mode. The first image correction factor is adjusted incrementally (1310) during a normal operation mode. A radio frequency (RF) signal associated with the first signal band is received (1324) using the first image correction factor during the normal operation mode.

Abstract: A method of operating a radio-frequency (RF) circuitry and a signal-processing circuitry in a mobile telephone apparatus includes at least partially disabling the signal-processing circuitry while transmitting or receiving signals. In one example, a processor is efficiently disabled by generating and servicing an interrupt of relatively high priority. One advantage of this example is that preexisting, legacy code can be maintained, while still achieving the desired objectives. The processor can be enabled by generating and servicing a second high priority interrupt.

Abstract: A method of operating a radio-frequency (RF) circuitry and a signal-processing circuitry in a mobile telephone apparatus includes at least partially disabling the signal-processing circuitry while transmitting or receiving signals. In one example, a processor is efficiently disabled by generating and servicing an interrupt of relatively high priority. One advantage of this example is that preexisting, legacy code can be maintained, while still achieving the desired objectives. The processor can be enabled by generating and servicing a second high priority interrupt.

Abstract: A method of operating a radio-frequency (RF) circuitry and a signal-processing circuitry in a mobile telephone apparatus includes at least partially disabling the signal-processing circuitry while transmitting or receiving signals. In one example, a processor is efficiently disabled by generating and servicing an interrupt of relatively high priority. One advantage of this example is that preexisting, legacy code can be maintained, while still achieving the desired objectives. The processor can be enabled by generating and servicing a second high priority interrupt.

Abstract: A communication apparatus includes a radio frequency circuit that operates on a radio frequency signal and a digital processing circuit coupled to the radio frequency circuit. The digital processing circuit includes a first timing circuit that provides timed signals to control timing of system operations during an active mode of operation of the digital processing circuit, and a second timing circuit that provides timing signals to control timing of system operations during an active mode of operation of the radio frequency circuit. In one particular embodiment, at least a portion of the first timing circuit is disabled when the radio frequency circuit is active (receiving and/or transmitting).

Abstract: A communication apparatus includes a radio frequency circuit that operates on a radio frequency signal and a digital processing circuit coupled to the radio frequency circuit. The digital processing circuit includes a plurality of bus masters coupled to a shared bus. A bus arbiter is provided for arbitrating between requests to access the bus by a first bus master and one or more other bus masters. Accesses by the one or more other bus masters to the bus are restricted in response to a signal indicative of a change in a mode of operation of the RF circuit. In one particular implementation, a communication apparatus employs time domain isolation wherein the digital processing circuit may be placed in a shutdown mode when the radio frequency circuit is active.

Abstract: A method of operating a radio-frequency (RF) circuitry and a signal-processing circuitry in a mobile telephone apparatus includes at least partially disabling the signal-processing circuitry while transmitting or receiving signals. In one example, a processor is efficiently disabled by generating and servicing an interrupt of relatively high priority. One advantage of this example is that preexisting, legacy code can be maintained, while still achieving the desired objectives. The processor can be enabled by generating and servicing a second high priority interrupt.

Abstract: Radio-frequency (RF) apparatus includes receiver analog circuitry that receives an RF signal and provides at least one digital signal to receiver digital circuitry that functions in cooperation with the receiver analog circuitry. The receiver analog circuitry and the receiver digital circuitry are partitioned so that interference effects between the receiver analog circuitry and the receiver digital circuitry tend to be reduced.