Abstract: A method and a circuit for high-efficiency linear RF-power amplification over a wide range of amplitudes from zero to peak output includes a final RF-power amplifier operating at or near saturation, an RF driver amplifier, a high-level amplitude modulator for the final amplifier, preferably a high-level amplitude modulator for the driver amplifier, and a means for determining the supply-voltage input to the final amplifier and for controlling the amplitude of the drive. The means for determining the supply-voltage input and for controlling the amplitude acts so that the final amplifier drive varies from a minimum level to peak as the desired transmitter output varies from zero to peak. The transmitter is preferably of the envelope-elimination-and-restoration type or the envelope-tracking type.

Abstract: A method and apparatus for efficient power amplification of a wideband signal with a correspondingly wide modulation bandwidth includes an envelope detector (220), an adaptive split band modulator (270), and a power amplifier (260). The adaptive split band modulator (270) amplifies the low frequency components using a class S modulator (760), and amplifies the high frequency components using a class B amplifier (750). The power supply of the class B amplifier (750) is adaptively modified as a function of the amplitude of the signal that it amplifies. In this manner, the class B amplifier (750) operates at a higher efficiency.

Abstract: A method and apparatus for efficient power amplification of a wideband signal with a correspondingly wide modulation bandwidth includes an envelope detector (220), an adaptive split band modulator (270), and a power amplifier (260). The adaptive split band modulator (270) amplifies the low frequency components using a class S modulator (760), and amplifies the high frequency components using a class B amplifier (750). The power supply of the class B amplifier (750) is adaptively modified as a function of the amplitude of the signal that it amplifies. In this manner, the class B amplifier (750) operates at a higher efficiency.

Abstract: A method and apparatus for efficient power amplification of a high dynamic range signal includes an envelope detector (220), a multi-range modulator (270), and a power amplifier (260). The multi-range modulator (270) efficiently amplifies the envelope of the input signal by selecting a power source as a function of the amplitude of the input signal. Multi-range modulator (200) produces a pulsewidth modulated signal with a duty cycle and an amplitude. When the amplitude of the input signal rises above a reference, the duty cycle and the amplitude are modified so as to keep the multi-range modulator in an operating region of high efficiency.

Abstract: Apparatus for determining the position and orientation of a remote object relative to a reference coordinate frame is disclosed. A plurality of radiating means having orthogonal components are centered about the origin of the reference coordinate frame. Means are provided for applying to the radiating means electrical signals which generate a plurality of electromagnetic fields. The electromagnetic fields are multiplexed and thus are distinguishable from one another. A plurality of receiving means are disposed on the remote object, the receiving means having orthogonal components for detecting and measuring components of the electromagnetic fields. The radiating means and receiving means are separated by a distance sufficiently large to insure that the far-field components of the electromagnetic fields are substantially greater in magnitude than the near-field components of the electro-magnetic fields.

Abstract: Two mutually orthogonal radiating antennas each transmit electromagnetic radiation to three mutually orthogonal receiving antennas. The transmitted electromagnetic radiation carries data characterizing the phase and magnetic moment of the electromagnetic radiation. Measurement of the two transmitted signals as received by the set of three orthogonal receiving antennas produces information which, in combination with two known position or orientation parameters, is sufficient to determine in a noniterative manner the six position and orientation parameters of the receiving antennas with respect to the radiating antennas. Use of only two radiating antennas increases the speed of the system and simplifies the transmitter. Alternatively, three radiating antennas and two receiving antennas may be provided to simplify the receiver.

Abstract: Three mutually orthogonal radiating antennas each transmit electromagnetic radiation to three mutually orthogonal receiving antennas. The transmitted electromagnetic radiation carries data characterizing the phase of the electromagnetic radiation. Measurement of the three transmitted signals as received by the set of three orthogonal receiving antennas produces nine parameters which, in combination with one known position or orientation parameter, are sufficient to determine the position and orientation parameters of the receiving antennas with respect to the position and orientation of the radiating antennas.