Abstract: This disclosure includes embodiments of a radio frequency (RF) transceiver having a distributed duplex filtering topology. The RF transceiver includes a power amplifier and a tunable RF duplexer. The tunable RF duplexer is configured to input an RF transmission input signal from the power amplifier, generate an RF transmission output signal that operates within an RF transmission band in response to the RF transmission input signal from the power amplifier, and simultaneously output the RF transmission output signal to an antenna and input an RF receive input signal that operates within an RF receive band from the antenna. The power amplifier includes a plurality of RF amplifier stages coupled in cascode and an RF filter coupled between a first one of the RF amplifier stages and a second one of the RF amplifier stages. Accordingly, the RF filter is configured to provide tuning within the RF receive band.

Abstract: A bus interface system is disclosed that includes a master bus controller and a slave bus controller that are coupled by a bus line. The slave bus controller includes a decoder that allows for data to be transmitted along just the bus line. The decoder includes an oscillator, a first counter, and a comparison circuit. The oscillator is configured to be enabled by data pulses defined by the input data signal and generate oscillation pulses while enabled. The first counts the oscillation pulses and indicates a number of the oscillation pulses generated during a time slot. The comparison circuit is configured to this number with a reference number and generate a data output that represents a first logical value in response to the number being greater than the reference parameter and represents a second logical value in response to the number being less than the reference parameter.

Abstract: A tunable radio frequency (RF) duplexer is disclosed. The tunable RF duplexer includes a first hybrid coupler, a second hybrid coupler, and an RF filter circuit. The first hybrid coupler is operable to split an RF receive input signal into first and second RF quadrature hybrid receive signals (QHRSs). The first hybrid coupler is also operable to split an RF transmission input signal into first and second RF quadrature hybrid transmission signals (QHTSs). The RF filter circuit is operable to pass the first and second RF QHRSs to the second hybrid coupler and to reflect the first and second RF QHTSs back to the first hybrid coupler. Additionally, the second hybrid coupler is configured to combine the first and second RF QHRSs into an RF receive output signal, while the first hybrid coupler is configured to combine the first and second RF QHTSs into an RF transmission output signal.

Abstract: Antenna tuning circuitry includes an antenna tuning node, an antenna tuning switch, and a resonant tuning circuit. The antenna tuning node is coupled to a resonant conduction element of an antenna. The antenna tuning switch and the resonant tuning circuit are coupled in series between the antenna tuning switch and the antenna tuning node, such that the resonant tuning circuit is between the antenna tuning node and the antenna tuning switch. The resonant tuning circuit is configured to resonate at one or more harmonic frequencies generated by the antenna tuning switch such that a high impedance path is formed between the antenna tuning switch and the antenna tuning node at harmonic frequencies generated by the antenna tuning switch. Accordingly, harmonic interference generated by the antenna tuning switch is prevented from reaching the antenna, while simultaneously allowing for tuning of the antenna.

Abstract: A phase shifting stage is disclosed. The phase shifting stage includes first and second transistors. Second terminals of the first transistor and the second transistor are coupled to a first current tail node. A third transistor and a fourth transistor have second terminals that are coupled to a second current tail node. Also included is a first transformer having a primary winding with first and second inputs and a secondary winding. The first input is coupled to the first terminals of the first and third transistors, and the second input is coupled to the first terminals of the second and the fourth transistors. A common input stage having high power gain and phase commutating cascode stages in asymmetrical transformer output demultiplexing (ATODEM) branches is also provided. The common input stage limits the noise generated at an input stage by substantially canceling out the noise at an output transformer of the ATODEM.

Abstract: A signal line sharing protocol and hardware permit control of a remotely located active device configured to provide different load configurations to an antenna. As an example, the communication system may include a master device. The master device may include a general purpose output and a radio frequency port. The communication system may further include a first duplexer and a second duplexer. The first duplexer may include a first port, a second port, and a third port, where the second port is coupled to the radio frequency port and the third port is coupled to the general purpose output of the master device. The second duplexer may include a first port, a second port, and a third port, where the first port of the second duplexer is in communication with the first port of the first duplexer, wherein the second port is coupled to an antenna, and where the third port is in communication with a slave device. The slave device may be coupled to the antenna.

Abstract: The embodiments disclosed in the detailed description include a power amplifier having a low power mode amplifier, a medium power mode amplifier, and a high power mode amplifier in communication with a radio frequency (RF) output load. The exemplary embodiments of the power amplifier permit a wireless device to select the most power efficient means to transmit an RF signal based upon the desired output power level.

Abstract: An asymmetrical transformer output demultiplexing (ATODEM) circuit is disclosed. The ATODEM circuit of the present disclosure includes N input windings, wherein N is a natural number. Each of the N input windings have input terminals that couple to output terminals of N PAs. The ATODEM further includes M output ports wherein M is a natural number, each of the M output ports having N series coupled windings coupled between a load terminal and a return terminal. The physical attributes of the N input windings, and the N series coupled windings of the M output ports are asymmetrical such that in an Nth operation mode an Nth PA first-load line impedance matches an output impedance of an Nth PA coupled to the input terminals.

Abstract: The present disclosure relates to a multi-band RF power amplifier (PA) module, which is used to receive, filter, and amplify a first RF input signal to provide a first RF output signal using a first tunable bandpass and notch filter. The multi-band RF PA module may include a supporting substrate having at least a first inductive element that provides a first portion of the first tunable bandpass and notch filter. Further, the multi-band RF PA module may include at least a first semiconductor die, which is attached to the supporting substrate and provides a second portion of the first tunable bandpass and notch filter. A transceiver module may provide the first RF input signal.

Abstract: Adjustable impedance tuning circuitry includes a first impedance matching terminal, a second impedance matching terminal, and a plurality of passive components adapted to match the impedance of the first impedance matching terminal and the second impedance matching terminal. The plurality of passive components includes one or more tunable components adapted to adjust the impedance of the adjustable impedance tuning circuitry to maintain an impedance match between the first impedance matching terminal and the second impedance matching terminal over a variety of operating conditions. Each of the one or more tunable components includes one or more switches adapted to selectively alter the impedance of the tunable component. The one or more switches are integrated onto a single semiconductor die in order to facilitate the performance of the adjustable impedance tuning circuitry over a wide bandwidth.

Abstract: The present disclosure relates to de-multiplexing at least one RF input signal feeding RF power amplifier circuitry to create multiple de-multiplexed RF output signals, which may be used to provide RF transmit signals in an RF communications system. Output transformer circuitry is coupled to outputs from the RF power amplifier circuitry to provide the de-multiplexed RF output signals, which may support multiple modes, multiple frequency bands, or both. The de-multiplexed RF output signals may be used in place of RF switching elements in certain embodiments. As a result, RF front-end switching circuitry in the RF communications system may be simplified, thereby reducing insertion losses, reducing costs, reducing size, or any combination thereof. Additionally, the output transformer circuitry may provide load line transformation, output transistor biasing, or both to the RF power amplifier circuitry.

Abstract: The disclosure describes a dual hybrid duplexer including two hybrid couplers, two intra-filters, a tunable isolation load, and a phase shifter. The phase shifter may be located at the isolation port. The phase shifter may be located at the antenna port. In one embodiment, a dual hybrid duplexer includes two hybrid couplers, two intra-filters, a tunable isolation load, a first phase shifter located at the isolation port, and a second phase shifter located at the antenna port. The first and second phase shifters have a difference of 90 degrees (plus or minus 10 degrees).

Abstract: This disclosure relates to hybrid couplers for radio frequency (RF) signals. The hybrid coupler includes a first port, a second port, a third port, a fourth port, a first inductive element connected from the first port to the third port, and a second inductive element connected from the second port to the fourth port. The hybrid coupler further includes a first capacitive element and a second capacitive element. The first capacitive element is connected between an intermediary node of the first inductive element and either the first port or the third port, while the second capacitive element is coupled between an intermediary node of the second inductive element and either the second port or the fourth port. Accordingly, the first capacitive element and a portion of the first inductive element and the second capacitive element and a portion of the second capacitive element each form a harmonic trap.

Abstract: The present disclosure relates to de-multiplexing at least one RF input signal feeding RF power amplifier circuitry to create multiple de-multiplexed RF output signals, which may be used to provide RF transmit signals in an RF communications system. Output transformer circuitry is coupled to outputs from the RF power amplifier circuitry to provide the de-multiplexed RF output signals, which may support multiple modes, multiple frequency bands, or both. The de-multiplexed RF output signals may be used in place of RF switching elements in certain embodiments. As a result, RF front-end switching circuitry in the RF communications system may be simplified, thereby reducing insertion losses, reducing costs, reducing size, or any combination thereof. Additionally, the output transformer circuitry may provide load line transformation, output transistor biasing, or both to the RF power amplifier circuitry.

Abstract: Radio frequency (RF) front end circuitry includes a notch diplexer. The notch diplexer includes a high pass filter coupled between a high band port and an antenna port, and a low pass notch filter coupled between a low band port and the antenna port. The high pass filter is adapted to receive a high band receive signal having a high band carrier frequency at the antenna port, and pass the high band receive signal to the high band port. The low pass notch filter is adapted to receive a low band transmit signal having a low band carrier frequency at the low band port, and attenuate distortion in the low band transmit signal about a notch stop band before passing the low band transmit signal to the antenna port. According to one embodiment, the notch stop band includes the high band carrier frequency.

Abstract: A radio frequency (RF) circuit including control circuitry adapted to select one of multiple modes, including a first transmit mode and a first receive mode. The first receive circuitry is coupled to a first node, and the first node is coupled to a first antenna. During the first receive mode the first receive circuitry is adapted to receive a first RF input signal having a first receive frequency. First power amplifier circuitry including a first final stage provides a first RF output signal having a first transmit frequency for transmission from the first antenna during the first transmit mode. First impedance transformation circuitry is coupled between an output of the first final stage and the first node. During the first receive mode the first final stage is disabled and the first final stage and the first impedance transformation circuitry present a substantially high impedance to the first node.

Abstract: The present disclosure relates to an RF power amplifier (PA) power supply that includes a series pass circuit coupled across a direct current (DC)-to-DC converter to receive a power supply input signal, such as provided from a battery, to provide a power supply output signal to at least a first RF PA based on an output setpoint. Control circuitry selects between a switching supply operating mode and a non-switching supply operating mode based on the output setpoint. During the switching supply operating mode, the DC-to-DC converter provides the power supply output signal and during the non-switching supply operating mode, the series pass circuit provides the power supply output signal.

Abstract: The embodiments disclosed in the detailed description include a power amplifier having a low power mode amplifier, a medium power mode amplifier, and a high power mode amplifier in communication with a radio frequency (RF) output load. The exemplary embodiments of the power amplifier permit a wireless device to select the most power efficient means to transmit an RF signal based upon the desired output power level.

Abstract: The embodiments disclosed in the detailed description include a power amplifier having a low power mode amplifier, a medium power mode amplifier, and a high power mode amplifier in communication with a radio frequency (RF) output load. The exemplary embodiments of the power amplifier permit a wireless device to select the most power efficient means to transmit an RF signal based upon the desired output power level.

Abstract: A phase shifting stage is disclosed. The phase shifting stage includes first and second transistors. Second terminals of the first transistor and the second transistor are coupled to a first current tail node. A third transistor and a fourth transistor have second terminals that are coupled to a second current tail node. Also included is a first transformer having a primary winding with first and second inputs and a secondary winding. The first input is coupled to the first terminals of the first and third transistors, and the second input is coupled to the first terminals of the second and the fourth transistors. A common input stage having high power gain and phase commutating cascode stages in asymmetrical transformer output demultiplexing (ATODEM) branches is also provided. The common input stage limits the noise generated at an input stage by substantially canceling out the noise at an output transformer of the ATODEM.