Abstract: The present invention provides a method and apparatus for supplying power to a load at a plurality of different power levels. The method includes changing between high and low power outputs of the power amplifier when amplifying a signal having a common modulation format. A different bias is applied to the power amplifier at the low power output than the bias applied to the power amplifier at the high power output. The output of the power amplifier is loaded with a different impedance at the low power output than the impedance loaded at the output of the power amplifier output at the high power output. In at least one embodiment, the power amplifier changes between high and low power outputs at a different threshold level dependant upon whether the power amplifier is transitioning from the high power output to the low power output, or whether the power amplifier is transitioning from the low power output to the high power output.

Abstract: A method (800) and an apparatus for controlling transmission power associated with a transmitting unit (220) are described herein. The transmitting unit (220) generally includes a processing component (310), a baseband controller (320), a linearization controller (330), a variable baseband source (340), and a radio frequency (RF) component (350). The variable baseband source (340) may generate a baseband signal based on an input signal. The RF component (350) may generate an RF signal based on the baseband signal. The processing component (310) may generate a first control signal and a second control signal. Further, the processing component (310) may provide the first control signal to the baseband controller (320) to adjust the variable baseband source (340), and provide the second control signal to the linearization controller (330) to adjust the RF frequency component (350).

Abstract: The present invention provides a method and apparatus for supplying power to a load at a plurality of different power levels. The method includes changing between high and low power outputs of the power amplifier when amplifying a signal having a common modulation format. A different bias is applied to the power amplifier at the low power output than the bias applied to the power amplifier at the high power output. The output of the power amplifier is loaded with a different impedance at the low power output than the impedance loaded at the output of the power amplifier output at the high power output. In at least one embodiment, the power amplifier changes between high and low power outputs at a different threshold level dependant upon whether the power amplifier is transitioning from the high power output to the low power output, or whether the power amplifier is transitioning from the low power output to the high power output.

Abstract: The present invention provides a method and apparatus for supplying power to a load at a plurality of different power levels. The method includes changing between high and low power outputs of the power amplifier when amplifying a signal having a common modulation format. A different bias is applied to the power amplifier at the low power output than the bias applied to the power amplifier at the high power output. The output of the power amplifier is loaded with a different impedance at the low power output than the impedance loaded at the output of the power amplifier output at the high power output. In at least one embodiment, the power amplifier changes between high and low power outputs at a different threshold level dependant upon whether the power amplifier is transitioning from the high power output to the low power output, or whether the power amplifier is transitioning from the low power output to the high power output.

Abstract: A radio communications device 100 including a processor 120 having a digital signal processor (DSP) coupled to a transceiver 110. The transceiver includes a digital-to-phase synthesizer having one or more independently variable frequency or phase signal outputs coupled to a transmitter and/or to a receiver. The variable frequency and phase outputs of the digital-to phase synthesizer are mixed with corresponding received signals and are capable of frequency or phase modulating information signals for transmission. Amplitude modulated signals may be provided through polar modulation by combining synthesizer outputs at a summer.

Abstract: A power amplifier load adjust system includes a power amplifier and a variable impedance network coupled to the output of the power amplifier. The variable impedance network presents a plurality of impedances to the output of the power amplifier responsive to a load control signal. A control circuit generates a transmit power command and a channel frequency command. Memory stores a plurality of control values as a function of output power and frequency. A processing circuit coupled to the variable impedance network, the control circuit, and the memory retrieves the plurality of control values and uses them to generate the load control signal in response to the transmit power command and the channel frequency command.

Abstract: A power amplifier load adjust system includes a power amplifier and a variable impedance network coupled to the output of the power amplifier. The variable impedance network presents a plurality of impedances to the output of the power amplifier responsive to a load control signal. A control circuit generates a transmit power command and a channel frequency command. Memory stores a plurality of control values as a function of output power and frequency. A processing circuit coupled to the variable impedance network, the control circuit, and the memory retrieves the plurality of control values and uses them to generate the load control signal in response to the transmit power command and the channel frequency command.

Abstract: A radio frequency (RF) coupler apparatus (312) suited for use in a multi-band wireless communication device (200), has a termination device (316) and couplers (314 and 315). Each of the couplers (314 and 315) has through-path coupling elements (318 and 320) and coupled-path coupling elements (319 and 321). Through-path coupling elements (318 and 320) pass a RF signal that is to be transmitted respective frequency bands (TX BAND 1, TX BAND 2) within which the device (200) operates. Coupled-path coupling elements (319 and 321) couple the RF signals passed by respective through-path coupling elements (318 and 320). The coupled-path coupling elements (319 and 321) and the termination device (316) are coupled in series, thereby permitting compatibilty with a RF power detector (313) that uses a single detection diode (322).

Abstract: An amplifier system to increase the efficiency of amplification systems that employ linear modulation schemes. The amplifier system has a signal amplifier for receiving a constant amplitude input signal and producing an amplified version of the input signal. A variable impedance network presents various impedances to an output of the signal amplifier responsive to a load control signal. An envelope mapping circuit coupled to the variable impedance network produces the load control signal responsive to a desired amplitude modulation (AM) envelope. The various impedances causes the desired AM envelope to be impressed upon the amplified version of the input signal.

Abstract: A load envelope following (LEF) amplifier system to increase the efficiency of amplification systems that employ linear modulation schemes. The LEF system has a signal amplifier for receiving an input signal that has an amplitude modulation (AM) envelope. The signal amplifier produces an amplified version of the input signal. A variable impedance network is coupled to an output of the signal amplifier and substantially continuously presents various impedances to the output of the signal amplifier in response to a load control signal. An envelope mapping circuit is coupled to the variable impedance network to produce the load control signal in response to and indicative of the substantially continuously varying amplitude of the AM envelope of the input signal.

Abstract: A modulation format switch in signal communication with an amplifier, which produces a plurality of modulation format signals, and a load is described. The modulation format switch includes at least one matching network in signal communication with the amplifier and the load, where the at least one matching network capable of having a plurality of impedance values corresponding to the plurality of modulation format signals. The modulation format switch also includes a controllable element in the matching network, the controllable element capable of having more than one impedance value.

Abstract: A power amplifying circuit with load adjust for control of adjacent and alternate channel power. A power amplifier amplifies an input signal to produce an amplified signal. A variable impedance network presents different impedances to the output of the power amplifier responsive to a load control signal. A peak-to-average detector provides an indication of a peak-to-average ratio of the amplified signal. A controller coupled to the peak-to-average detector and the variable impedance network produces the load control signal responsive to the indication of the peak-to-average ratio.

Abstract: According to the method and apparatus of the present disclosure, dual drain control uses a variable voltage supply on the drains of a first stage (302) and a second stage (304) to control the output power. In particular, dual drain control having a 1:1 ratio is employed at lower power levels, with single drain control at higher power levels. Such drain control could be employed by directly varying (1008, 1010) the voltage on the drains of the power amplifier, such as with signals from a microprocessor, or by a specific circuit (203) to generate the drain voltages based upon a control voltage.

Abstract: A transmitter (107) includes amplifying circuitry (203) and control circuitry (215, 217, 219) for biasing the amplifying circuitry (203) so that it operates closer to saturation with increased efficiency. The gate voltage signal (213), which provides a gate bias, is coupled to the amplifying circuitry (203) and is dynamically varied by the processor circuitry (219) in response to the value of the amplifier control voltage (211) coupled to the amplifying circuitry (203). The amplifier control voltage (211), which has a value for maintaining the output power of the amplifying circuitry (203) at a constant, is produced by the integrating circuitry (217) in response to a comparison of the detected power output signal (216) produced by the detecting circuitry (215) and the power output control signal (218) produced by the processor circuitry (219).

Abstract: A transmission line coupler (115) for a transmitter output signal (123) generated by an RF signal amplifier (103) includes a through-path transmission line (201) and a coupled-path transmission line (202) electromagnetically coupled thereto by multiple serpentine-like portions (such as portions 641, 642, 643 and 644 in FIG. 6 ), which are disposed on opposite sides of the through-path transmission line (201) for enhancing coupling sensitivity and eliminating degradation in the amount of coupling due to variations in the transmission line plating registration. Offset portions (641, 643) on one side of the through-path transmission line (201) provide substantially the same amount of coupling as the offset portions (642,643) on the other side of the through-path transmission line (201).