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    TEMPERATURE COMPENSATED AUTOMATIC OUTPUT CONTROL CIRCUITRY FOR RF SIGNAL POWER AMPLIFIERS WITH WIDE DYNAMIC RANGE
    74.
    发明专利
    TEMPERATURE COMPENSATED AUTOMATIC OUTPUT CONTROL CIRCUITRY FOR RF SIGNAL POWER AMPLIFIERS WITH WIDE DYNAMIC RANGE 未知

    公开(公告)号：CA1210071A

    公开(公告)日：1986-08-19

    申请号：CA462541

    申请日：1984-09-06

    Applicant: MOTOROLA INC

    Inventor： WALCZAK THOMAS J ,  STONE RICHARD M ,  CRISTIANO GARY M

    IPC: H04B1/04

    Abstract: Improved temperature compensated, automatic output control (AOC) circuitry for RF signal power amplifiers is described that maintains the output power within one-half dB of a selected one of eight power levels varying from nine milliwatts to five watts, a dynamic range of twenty-eight dB. The amplification of the RF signal amplifier is proportional to a drive current signal provided by a current amplifier. A half-wave rectifier is coupled to the output of final amplifiers for generating an output power signal that has a magnitude proportional to the output power. The half-wave rectifier is temperature compensated for and biased by a diode coupled to the rectifier by one resistor and coupled to supply voltage by another resistor. The output power voltage is further coupled to an amplifier having an amplification factor selected by level control signals. The amplified output power signal is coupled to a comparator which varies the drive current provided by the current amplifier in response to the voltage difference between the amplified output power signal and a reference voltage.

    Communication device with rotatable housings
    76.
    发明专利
    Communication device with rotatable housings 未知

    公开(公告)号：GB2351201A

    公开(公告)日：2000-12-20

    申请号：GB0024802

    申请日：1997-06-11

    Applicant: MOTOROLA INC

    Inventor： HARRIS DARYL ROBERT ,  WILLIAMS DANIEL LAWRENCE ,  WALCZAK THOMAS J

    IPC: H04M1/02 ,  H04M1/247 ,  H04M1/2745 ,  H04M1/725

    Abstract: A communication device 104 includes two housings 108, 110 each containing circuitry for operating the communication device in different modes (figure 7). The communication device includes a latch (112, figure 5) for rotating one housing with respect to the other. The switches between different operating modes depending on the relative position of the two housings. Operating modes may also be selected by the user and may include telephone, video conferencing, camera, phonebook, and notepad.

    APPARATUS AND METHOD FOR GENERATING A TRANSITION BETWEEN THE ON AND OFF STATES OF A RADIO FREQUENCY TRANSMITTER
    79.
    发明专利
    APPARATUS AND METHOD FOR GENERATING A TRANSITION BETWEEN THE ON AND OFF STATES OF A RADIO FREQUENCY TRANSMITTER 未知

    公开(公告)号：CA2087845C

    公开(公告)日：1997-11-04

    申请号：CA2087845

    申请日：1992-06-19

    Applicant: MOTOROLA INC

    Inventor： GREENE ROBERT I ,  CAHILL STEPHEN V ,  WALCZAK THOMAS J ,  DIEHL JOHN W

    IPC: H04L27/20 ,  H03G3/20 ,  H03G3/30 ,  H04B7/005 ,  H04B15/04 ,  H04B1/04 ,  H04Q7/32

    Abstract: An apparatus and method generates a shaped transition between the minimum and maximum output power levels of a transmitter (500). When the transmitter is turned on a stepped transition (415) is generated at the beginning (3) of the transition region (409) followed by a shaped transition (417) to the end (6) of the transition region (409). When the transmitter (500) is turned off a shaped transition region (417') is generated at the beginning (162) of the transition region (411) followed by a stepped transition (415') at the end (3) of the transition region (411). The stepped transition (415 or 415') is generated by adjusting a voltage controlled attenuator (545) and the bias of a power amplifier (545) in the transmitter (500). The shaped transition (417 or 417') is generated by processing transmitted information through finite impulse response filters (507 or 509) before or after the time slot permitted for transmitting information.

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