Omnipoint Corporation

Cleveland Medical Devices Inc.

Intel Corporation

Timeback Fll

Farron L Dacus

Russell A Morris

Steven P Hendrix

Robert N Schmidt

Apparatus and methods are provided for regulating the power consumption within a wireless communications mobile handset. A base station transmits an RF power output designating signal that indicates a desired level of the RF power output from the mobile handset. The mobile handset receives the RF power output designating signal, where it is used to set the level of the DC power supplied to the mobile handset. In this manner, the minimum amount of power necessary to maintain linear operation of the mobile handset is expended in the mobile handset. The DC power level is set by internally generating a control signal. The level of the control signal is dictated by the desired level of the RF power output as indicated by the received RF power output designating signal. The control signal is then applied to an RF amplifier circuit contained within the mobile handset to set the DC power level. The DC power level can be further varied from the set DC power level in proportion to an envelope of an RF input signal to provide a more power-efficient mobile handset.

Methods and apparatus for adjusting DC power consumption in mobile handset

An apparatus for low power radio communication comprising a transmitter having a frequency synthesizer and transmit antenna such that the frequency synthesizer comprises a phase locked loop circuit with a voltage controlled oscillator having a variable frequency output and with a loop filter/sample and hold circuit that allows opening of the synthesizer control loop and with special means of limiting the resulting frequency drift in the open loop state. The transmitter produces an output signal and the loop filter/sample and hold circuit holds the voltage controlled oscillator substantially on frequency such that the output signal remains stable, with a minimum of frequency drift, over a period of time when the phase lock loop synthesizer is set to an open loop state to allow frequency modulation unimpeded by the normal frequency correcting action of the synthesizer and for the frequency synthesizer to be partially powered down to reduce power consumption. The frequency modulation is linearized over a band of interest and undesired frequency shift at the initiation of modulation is suppressed. Receiver having automatic frequency control is included to extend the open loop transmit time of the transmitter, where the automatic frequency control system automatically tunes the receiver to correct for frequency error and for the frequency drift resulting from opening the phase locked loop of the frequency synthesizer, allowing communications to continue in the presence of such drift and of other frequency error.

Apparatus for low power radio communications

The present invention relates to a frequency modulated system, and a method for operating same, including a phase locked loop frequency synthesizer circuit which synthesizes a carrier frequency through the use of an electronically controlled oscillator. The circuit, which has a certain loop bandwidth, includes a reference frequency source and a bypassed correcting integrator. A modulating signal simultaneously modulates the oscillator, the reference frequency source and the bypassed correcting integrator such that the carrier frequency is frequency modulated with a certain frequency deviation. The magnitude of the modulation of the oscillator, the reference frequency source and the correcting integrator are controlled over a frequency range by frequency blending the reference frequency source and the bypassed correcting integrator such that low distortion modulation over a wide frequency range is achieved.

Three point modulated phase locked loop frequency synthesis system and method

An adaptable DC power consumption circuit is provided, wherein a controller alternately operates an RF amplifier during a high RF output power condition, and bypasses the RF amplifier during a low RF output power condition. In this manner, linear operation of the RF amplifier can be maintained while maximizing the power efficiency of the RF amplifier.

Bypassable amplifier

An adaptable DC power consumption circuit is provided, wherein the voltage supplied to an RF amplifier is dynamically varied from a desired level. A feedback control loop is formed between the power terminal and a control terminal of a variable voltage supply. A controller influences the feedback control loop to properly set the supply voltage at the desired minimum level necessary to maintain linear operation of the RF amplifier. The output of the RF amplifier influences the feedback control loop to dynamically vary the supply voltage from the desired level. In this manner, linear operation of the RF amplifier can be maintained while maximizing the power efficiency of the RF amplifier.

Amplifier with dynamatically adaptable supply voltage

An adaptable DC power consumption circuit is provided, wherein the current supplied to an RF amplifier is dynamically varied from a desired level. A feedback control loop is formed between the power terminal and the control terminal of the RF amplifier. A controller influences the feedback control loop to properly set the supply current at the desired minimum level necessary to maintain linear operation of the RF amplifier. The output of the RF amplifier influences the feedback control loop to dynamically vary the supply current from the desired level. In this manner, linear operation of the RF amplifier can be maintained while maximizing the power efficiency of the RF amplifier.

Amplifier with dynamically adaptable supply current

A receiver for efficient wireless communications in the presence of frequency errors in a radio frequency received signal is disclosed. The receiver comprising a receiver channel, a wide band frequency acquisition mode, automatic frequency control, a narrow band demodulation mode and a demodulator. The receiver channel has a variable bandwidth and an approximately fixed receiver mid-channel frequency. The wide band frequency acquisition mode comprises a wide channel filter which initially defines the bandwidth to be greater than the frequency error in the received signal and wherein the frequency error is determined by comparing the received signal frequency to the receiver mid-channel frequency. The automatic frequency control comprises at least one frequency adjustable local oscillator which it adjusts based upon the frequency error such that the frequency difference between the receiver mid-channel frequency and the received signal is made negligible, thereby approximately centering the received signal within the bandwidth in the wide band frequency acquisition mode. The narrow band demodulation mode comprises a narrower channel filter which narrows the bandwidth of the receiver channel with respect to the wide band frequency acquisition mode and maintains approximately the same receiver mid-channel frequency. The demodulator demodulates the received signal in the narrow band demodulation mode. Automatic frequency control and bandwidth selection using-adaptive digital signal processing based filters is also disclosed. In this case instead of the local oscillator being adjusted to tune in the desired signal, the filter center frequency is adapted.

Apparatus and method for efficient wireless communications in the

A frequency locked loop frequency synthesizer is comprised of a loop including a voltage controlled oscillator, a phase lock locked loop frequency detector, a divide by N counter and a low pass loop filter. A steering voltage is applied to the loop filter to produce a desired frequency or frequencies. The frequency lock loop frequency synthesizer drives the voltage controlled oscillator frequency to be N times the reference frequency. The frequency lock loop synthesizer inherently has 90 degrees less loop phase shift than a conventional phase lock loop. Additionally, the frequency lock loop frequency synthesizer provides a highly accurate, continuously tuneable, frequency synthesizer that includes a linear frequency detector in the frequency lock loop.

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Irving, TX, United States of America

Farron L Dacus