Abstract: Functionality can be implemented to calibrate the output transmit power of a power amplifier of a network device without the use of test equipment. An RF signal can be transmitted at the saturated output power (of a power amplifier) from a transmitter unit to a receiver unit of the network device via a loopback path. A received power of the RF signal received via the loopback path can be measured. The loopback gain associated with the network device is determined based on the saturated output power and the measured received power. The output transmit power can be calibrated by iteratively decreasing the output transmit power by an unknown value, transmitting a new RF signal via the loopback path at the decreased output transmit power, measuring the new received power, and calculating the decreased output transmit power using the loopback gain and the measured new received power.

Abstract: Digital-to-analog conversion in a communication device typically results in superimposed spectral images in the frequency spectrum of the analog waveform. These superimposed spectral images can distort the analog waveform and potentially violate the spectral mask and the constraints on out-of-band emissions set by the FCC. The communication device can be configured to implement a spectral image cancellation unit with feed-forward architecture to minimize the spectral images in the frequency spectrum of the analog waveform. The spectral image cancellation unit can generate a spectral image error signal comprising the spectral images at one or more spectral image frequencies. The spectral image cancellation unit can then subtract the spectral image error signal from the analog waveform to reduce spectral image components of the analog waveform and to yield an output signal for transmission.

Abstract: Redundancies of power amplifiers (PAs) or low noise amplifiers (LNAs) at the front end of an RF device are used to reduce losses that typically occur at a diversity switch. A signal designator can advantageously be used to select designated signals, which are provided to the PAs for transmitting or provided by the LNAs during receiving.

Abstract: A wireless device includes a functional unit, a wireless transceiver, an antenna and a clock. The wireless transceiver and antenna are coupled to the functional unit. The clock is coupled to the functional unit and the wireless transceiver. The clock is generates a clock signal. The wireless device is coupled wirelessly to a wireless slave device. The functional unit is configured to determine an amount of time since a last keep alive transmission with the slave device has occurred based on the clock. The functional unit determines a number of keep alive transmissions to transmit to the slave device, and appropriate transmission times for the keep alive transmissions relative to a next scheduled keep alive transmission time, based on the determined amount of time since the last keep alive transmission. The functional unit begins successive transmission of the keep alive transmissions to the slave device per the transmission times.

Abstract: Digital-to-analog conversion in a communication device typically results in superimposed spectral images in the frequency spectrum of the analog waveform. These superimposed spectral images can distort the analog waveform and potentially violate the spectral mask and the constraints on out-of-band emissions set by the FCC. The communication device can be configured to implement a spectral image cancellation unit with feed-forward architecture to minimize the spectral images in the frequency spectrum of the analog waveform. The spectral image cancellation unit can generate a spectral image error signal comprising the spectral images at one or more spectral image frequencies. The spectral image cancellation unit can then subtract the spectral image error signal from the analog waveform to reduce spectral image components of the analog waveform and to yield an output signal for transmission.

Abstract: Multiple power amplifiers in an RF front end are coupled to multiple antennas without diversity switching between the PAs and antennas. Diversity switches direct signals to broadcast by a selected antenna to a PA coupled to the selected antenna. Multiple LNAs are similarly coupled to the diverse antennas. Having one PA and LNA set for each antenna removes the need for diversity switching between the PA/LNAs and each antenna improving signal reception. In one embodiment, a single external PA performs broadcast functions and plural on-chip LNAs are used for reception. In another embodiment, phase shifters are coupled to each PA and LNA, which provide beam forming capability for broadcasts, and in phase signal combinations for received signals.

Abstract: A wireless device includes a functional unit, a wireless transceiver, an antenna and a clock. The wireless transceiver and antenna are coupled to the functional unit. The clock is coupled to the functional unit and the wireless transceiver. The clock is generates a clock signal. The wireless device is coupled wirelessly to a wireless slave device. The functional unit is configured to determine an amount of time since a last keep alive transmission with the slave device has occurred based on the clock. The functional unit determines a number of keep alive transmissions to transmit to the slave device, and appropriate transmission times for the keep alive transmissions relative to a next scheduled keep alive transmission time, based on the determined amount of time since the last keep alive transmission. The functional unit begins successive transmission of the keep alive transmissions to the slave device per the transmission times.

Abstract: A dual band radio is constructed using a primary and secondary transceiver. The primary transceiver is a complete radio that is operational in a stand alone configuration. The secondary transceiver is a not a complete radio and is configured to re-use components such as fine gain control and fine frequency stepping of the primary transceiver to produce operational frequencies of the secondary transceiver. The primary transceiver acts like an intermediate frequency device for the secondary transceiver. Switches are utilized to divert signals to/from the primary transceiver from/to the secondary transceiver. The switches are also configured to act as gain control devices. Antennas are selected using either wideband or narrowband antenna switches that are configured as a diode bridge having high impedance at operational frequencies on control lines that bias the diodes.

Abstract: Multiple power amplifiers in an RF front end are coupled to multiple antennas without diversity switching between the PAs and antennas. Diversity switches direct signals to broadcast by a selected antenna to a PA coupled to the selected antenna. Multiple LNAs are similarly coupled to the diverse antennas. Having one PA and LNA set for each antenna removes the need for diversity switching between the PA/LNAs and each antenna improving signal reception. In one embodiment, a single external PA performs broadcast functions and plural on-chip LNAs are used for reception. In another embodiment, phase shifters are coupled to each PA and LNA, which provide beam forming capability for broadcasts, and in phase signal combinations for received signals.

Abstract: The present invention provides a variable gain amplifier with a plurality of gain stages in which each of the gain stages is implemented using a circuit that implements a neutralization approach. This variable gain amplifier provides stable operation characteristics as different gain stages within the variable gain amplifier are turned on and off. This variable gain amplifier also increases linearity across the entire operating range. Additionally, the variable gain amplifier of the present invention provides a constant input impedance through different gain settings. Further, the present invention provides a variable gain amplifier in which each of the various gain stages therein maximize the available voltage swing. Finally, this variable gain amplifier improves common-mode rejection performance and attenuates unwanted harmonics.

Abstract: The present invention provides a synthesizer having an efficient lock detect signal generator, an extended range VCO that can operate within any one of a plurality of adjacent characteristic curves defined by a plurality of adjacent regions, and a divide circuit implemented using only a single counter along with a decoder. This allows for a method of operating the synthesizer, methods of establishing or reestablishing a lock condition using the extended range VCO, and a method of designing a plurality of divide circuits which each use the same single counter and each use a different decoder.

Abstract: The present invention provides a variable gain amplifier with a plurality of gain stages in which each of the gain stages is implemented using a circuit that implements a neutralization approach. This variable gain amplifier provides stable operation characteristics as different gain stages within the variable gain amplifier are turned on and off. This variable gain amplifier also increases linearity across the entire operating range. Additionally, the variable gain amplifier of the present invention provides a constant input impedance through different gain settings. Further, the present invention provides a variable gain amplifier in which each of the various gain stages therein maximize the available voltage swing. Finally, this variable gain amplifier improves common-mode rejection performance and attenuates unwanted harmonics.

Abstract: The present invention provides a synthesizer having an efficient lock detect signal generator, an extended range VCO that can operate within any one of a plurality of adjacent characteristic curves defined by a plurality of adjacent regions, and a divide circuit implemented using only a single counter along with a decoder. This allows for a method of operating the synthesizer, methods of establishing or reestablishing a lock condition using the extended range VCO, and a method of designing a plurality of divide circuits which each use the same single counter and each use a different decoder.

Abstract: The present invention provides a synthesizer having an efficient lock detect signal generator, an extended range VCO that can operate within any one of a plurality of adjacent characteristic curves defined by a plurality of adjacent regions, and a divide circuit implemented using only a single counter along with a decoder. This allows for a method of operating the synthesizer, methods of establishing or reestablishing a lock condition using the extended range VCO, and a method of designing a plurality of divide circuits which each use the same single counter and each use a different decoder.

Abstract: The present invention provides a synthesizer having an efficient lock detect signal generator, an extended range VCO that can operate within any one of a plurality of adjacent characteristic curves defined by a plurality of adjacent regions, and a divide circuit implemented using only a single counter along with a decoder. This allows for a method of operating the synthesizer, methods of establishing or reestablishing a lock condition using the extended range VCO, and a method of designing a plurality of divide circuits which each use the same single counter and each use a different decoder.

Abstract: The present invention provides a synthesizer having an efficient lock detect signal generator, an extended range VCO that can operate within any one of a plurality of adjacent characteristic curves defined by a plurality of adjacent regions, and a divide circuit implemented using only a single counter along with a decoder. This allows for a method of operating the synthesizer, methods of establishing or reestablishing a lock condition using the extended range VCO, and a method of designing a plurality of divide circuits which each use the same single counter and each use a different decoder.

Abstract: The present invention provides a synthesizer having an efficient lock detect signal generator, an extended range VCO that can operate within any one of a plurality of adjacent characteristic curves defined by a plurality of adjacent regions, and a divide circuit implemented using only a single counter along with a decoder. This allows for a method of operating the synthesizer, methods of establishing or reestablishing a lock condition using the extended range VCO, and a method of designing a plurality of divide circuits which each use the same single counter and each use a different decoder.

Abstract: A mixing apparatus includes a Gilbert cell connected to a first load and a second load. In one embodiment each load contains transistors that are configured as a diode and a triode, where these circuits are additively combined to achieve substantially linear voltage-current characteristics over a predetermined range. The mixing apparatus takes two pairs of differential inputs and produces a pair of differential outputs. Because of the substantial linearity of the loads, the inputs and outputs of the mixing apparatus are acceptable over a relatively large range of input settings. In other embodiments each load may contain a transistor configured as a triode and a resistor, where these circuits are likewise additively combined to achieve substantially linear voltage-current characteristics over a predetermined range.

Abstract: A simple class CMOS AB amplifier capable of operating from a single 3 volt supply while driving a 2000 picofarad load.

Abstract: An operational amplifier drives the gate of a voltage controlled variation resistor having a source terminal coupled in series to a reference voltage through a current sense resistor and a drain terminal coupled in series to a supply voltage via a current regulated component, e.g., a light emitting diode. Voltage across the current sense resistor feeds back to the inverting input of the operational amplifier. The non-inverting input receives a substantially constant voltage corresponding to a target voltage, the voltage at the current sense resistor when the desired current flows therethrough. The operational amplifier varies the resistance of the variation resistor to maintain the target voltage at the current sense resistor and establish the desired current flow.