Abstract: A first radio receiver may be configured to receive an RF signal from an RF port and may comprise a first cascode amplifier configured to provide a primary RF signal on a primary path for processing by the first RF receiver and a bypass RF signal on a bypass path. A second radio receiver may be configured to receive a sum of the bypass RF signal and an amplified primary RF signal. As a result, the second radio receiver is coupled to the same RF port and the signal received by the second receiver is maintained constant irrespective of the RF signal current drawn by the first receiver. The product of the impedance of the tuned load of the first radio receiver and the gain of the amplifier amplifying the primary RF signal is set to unity.

Abstract: A wireless transceiver includes a receiver and a transmitter, the receiver and transmitter implemented to have multiple receive and transmit channels respectively, to provide multiple-input multiple-output (MIMO) capability. In an embodiment, the transceiver is implemented to include two transmit channels and two receive channels. Some blocks/circuitry of each of the receive and transmit channels are implemented with reduced area and current consumption, with a corresponding increase in noise. In a single-input single-output (SISO) mode of operation, the receiver combines the output of both the receive channels to compensate for the increase in noise due to the implementation with smaller area and lower current consumption. Similarly, the transmitter combines the output of both the transmit channels to compensate for the increase in noise. The transceiver operates with no signal degradation in SISO mode, and with a small degradation in signal quality in the MIMO mode.

Abstract: An electronic circuit comprising a transistor-based RF (radio frequency) power amplifier (112) having balanced outputs (172, 176), a transistor-based receiver RF amplifier (116) having balanced inputs (152, 156) ohmically connected to said balanced outputs (172, 176) respectively of said RF power amplifier (112), and a balun (114) having a primary (182, 186) and a secondary (188), said primary (182, 186) having primary connections and a supply connection (185) of said primary (182, 186) intermediate said primary connections and said primary connections ohmically connected both to said balanced outputs (172, 176) of said RF power amplifier (112) respectively and to said balanced inputs (152, 156) of said receiver RF amplifier, thereby to switchlessly couple RF between the balun (114) and the RF power amplifier (112) and switchlessly couple RF between the balun (114) and the receiver RF amplifier (116). Other electronic circuits, processes, devices and systems are disclosed.

Abstract: One embodiment of the present invention relates to a system that provides a high frequency local oscillator (LO) signal. The system comprises a first LO that generates a first frequency LO signal component, a mixer that generates a difference signal from the first frequency LO signal component and a second frequency LO signal component, and a second LO that generates the second frequency LO signal component that is a harmonic of the difference signal.

Abstract: One embodiment of the present invention relates to a system that provides a high frequency local oscillator (LO) signal. The system comprises a first LO that generates a first frequency LO signal component, a mixer that generates a difference signal from the first frequency LO signal component and a second frequency LO signal component, and a second LO that generates the second frequency LO signal component that is a harmonic of the difference signal.

Abstract: According to an aspect of the present invention, the magnitude and phase angle of looking-in impedance driven by an amplifier are computed in digital domain during normal operation within a module containing the amplifier. In an embodiment, the computed magnitude and phase angle are used for impedance matching at a node driven by the amplifier. As a result, impedance matching may be obtained even in situations when the impedance changes during operation.

Abstract: An active filter circuit includes an inductance-capacitance (LC) circuit (110) for wireless frequency input, a bi-directional mixer (120) and a filter impedance (130) series-coupled across at least part of the LC circuit (110), and another mixer (420) coupled to at least some portion of the LC circuit. Other circuits, processes, receivers, transmitters and transceivers are disclosed.

Abstract: A device includes multiple transceivers, a coupling block and an antenna. The transceivers operate according to time-division multiple access (TDMA) techniques. The coupling block is designed to enable the multiple transceivers to transmit or receive corresponding signals using the antenna. The multiple transceivers include a first transmitter and a second transmitter. The first transmitter is connected to the antenna via a first coupling network. The second transmitter is connected to the antenna via a series connection of a second coupling network and at least a portion of the first coupling network. Other transmitters are connected to the antenna via a series arrangement of at least a portion of the first coupling network and corresponding coupling networks.

Abstract: A circuit for sharing Tx/Rx ports of a CMOS based time multiplexed transceiver includes a Low Noise Amplifier (LNA) and a Power amplifier (PA), and deploys a single RF choke shared between the LNA and PA. The circuit selectively functions as a PA cascode or a LNA input device. In one form the circuit uses MOS transistors configured for use in one of Blue tooth, WLAN and TDMA applications, taking advantage of source-drain symmetry of the MOS transistors. The circuit may include a DC path and be used in WLAN applications, wherein the sharing of the single choke is enabled by one switch in the DC path. As described, the single RF choke is disposed outside of the LNA and the PA. The circuit supports high out powers and causes reduced signal loss due to just one LC tank as opposed to two LC tanks present in the prior art.

Abstract: A method, system, and apparatus of a DC current based on chip RF power detection scheme for a power amplifier are disclosed. In one embodiment, a method includes generating a scaled current from an other current associated with power amplifier, transforming the scaled current (e.g., the scaled current may be scaled to the other current value) into a digital signal and using the digital signal to set a radio frequency power value of an antenna of the antenna module. The method may include transforming the scaled current into a voltage signal. The method may also include transforming the voltage signal into the digital signal. The method may also include generating a current mirror from a low dropout regulator.

Abstract: A low-power receiver front-end includes a transconductance amplifier that produces a single-ended current signal in response to a single-ended voltage signal. An output of the transconductance amplifier is provided to an LC tuned circuit. At resonance, the LC tuned circuit generates a differential current signal in response to the single-ended current signal. Single-ended current signals corresponding to the resonant frequency of the LC tuned circuit are converted into differential signals. Further, the LC tuned circuit amplifies the differential current signals by an associated quality factor. Further, a mixer is coupled to an output of the LC tuned circuit. The mixer generates IF signals in response to the differential current signals.

Abstract: A circuit includes an antenna, and a pair of transceivers. A first transceiver in the pair is connected to the antenna via a first pair of feed-points, and is designed to transmit and receive signals in a first band of frequencies. A second transceiver in the pair is connected to the antenna via a second pair of feed-points, and is designed to transmit and receive signals in a second band of frequencies. The first band and the second band are non-overlapping frequency bands. The first pair of feed-points is located at a voltage null point of the antenna with respect to the second pair of feed-points. The second pair of feed-points is located at a voltage null point of the antenna with respect to the first pair of feed-points. The first transceiver and the second transceiver are, thus, enabled to simultaneously transmit and/or receive corresponding signals using the same antenna.

Abstract: A low-noise amplifier (LNA) includes a pair of transistors connected in a cascode configuration to provide amplification to an input signal. The LNA generates an amplified output in differential form across a pair of output terminals. One of the pair of output terminals is the output node of the cascode configuration. The LNA further includes a feedback transistor with its gate terminal connected to the output node of the cascode configuration and its drain terminal connected to the other one of the pair of output terminals. The differential nature of the amplified output reduces the noise figure of the LNA. A frequency-selective network connected across the pair of output terminals sets the frequency selectivity of each of the input section and the output section of the LNA.

Abstract: A near field communication (NFC) transceiver contains a transmitter portion to generate a transmit wireless signal, and a receiver portion to receive and process a receive wireless signal. The circuit further contains a shunt capacitor, a switch, and an antenna interface to couple the transmitter portion and the receiver portion to an antenna designed to communicate with external antennas by inductive coupling. The switch couples the shunt capacitor in parallel with the antenna in one operational mode, and decouples the shunt capacitor from the antenna in another operational mode. Transmit and receive performance of the NFC transceiver are enhanced as a result.

Abstract: Low noise amplifier circuit. The low noise amplifier circuit includes an amplifier that amplifies an input to provide an output. The amplifier is coupled to an input terminal. The circuit also includes a device in a cascode connection with the amplifier. The circuit further includes a tuning circuit coupled to the device to phase shift the output. Further, the circuit includes a feedback circuit that is responsive to a phase-shifted output to enhance gain of the amplifier. The feedback circuit is coupled to the tuning circuit and the amplifier.

Abstract: An amplifier has first and second differential outputs connected to first and second ends of one side of a balun. A second side of the balun, inductively coupled to the first side of the balun, has a center tap that is electrically coupled to a conductive path to a power supply reference node for the amplifier.

Abstract: A switched power amplifier contained in a circuit is implemented to receive a single-ended input signal and generate a single-ended output signal, the single-ended output signal being a power-amplified version of the single-ended input signal. The switched power amplifier provides high efficiency.

Abstract: A wireless transceiver includes a receiver and a transmitter, the receiver and transmitter implemented to have multiple receive and transmit channels respectively, to provide multiple-input multiple-output (MIMO) capability. In an embodiment, the transceiver is implemented to include two transmit channels and two receive channels. Some blocks/circuitry of each of the receive and transmit channels are implemented with reduced area and current consumption, with a corresponding increase in noise. In a single-input single-output (SISO) mode of operation, the receiver combines the output of both the receive channels to compensate for the increase in noise due to the implementation with smaller area and lower current consumption. Similarly, the transmitter combines the output of both the transmit channels to compensate for the increase in noise. The transceiver operates with no signal degradation in SISO mode, and with a small degradation in signal quality in the MIMO mode.

Abstract: Oscillator circuit for radio frequency transceivers. An oscillator circuit includes a first oscillator that generates a signal having a first frequency and a second oscillator that generates a signal having a second frequency. The oscillator circuit includes a mixer that is responsive to the signal having the first frequency and the signal having the second frequency to provide a signal having a third frequency and one or more frequency components. The oscillator circuit includes a filter that is responsive to the signal from the mixer to attenuate the one or more frequency components and provide a signal having a desired frequency. The oscillator circuit includes a correction circuit to correct a drift in at least one of the first frequency and the second frequency by controlling the second frequency, thereby correcting the drift in the third frequency and the desired frequency.

Abstract: A near field communication (NFC) transceiver contains a transmitter portion to generate a transmit wireless signal, and a receiver portion to receive and process a receive wireless signal. The circuit further contains a shunt capacitor, a switch, and an antenna interface to couple the transmitter portion and the receiver portion to an antenna designed to communicate with external antennas by inductive coupling. The switch couples the shunt capacitor in parallel with the antenna in one operational mode, and decouples the shunt capacitor from the antenna in another operational mode. Transmit and receive performance of the NFC transceiver are enhanced as a result.