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公开(公告)号：GB2301964B
公开(公告)日：2000-08-02
申请号：GB9611239
申请日：1996-05-30
Applicant: MOTOROLA INC
Abstract: A unique method and apparatus modifies the load impedance at the output of a power amplifier by varying a voltage variable capacitor (VVC) (310) to maximize the efficiency of the power amplifier (304). A comparator (509) generates amplifier control signal (211) based upon a detected power output signal (216) and a reference signal. In addition to providing power control, the control signal is also coupled to a VVC circuit (506) to control the output impedance of the power amplifier. In an alternate embodiment, a separate VVC control signal (527) based upon a comparison of the power control signal and the battery voltage is coupled to a VVC. In another alternate embodiment, a second VVC can be coupled in parallel to the first VVC. The second VVC is preferably controlled by a signal (805) based upon the current in the power amplifier. Finally, an alternate embodiment incorporates a VVC circuit (506) at the input of the power amplifier to compensate for variations in input impedance to improve other power amplifier parameters such as IM, gain, output power and noise level.
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公开(公告)号：BR9602624A
公开(公告)日：1998-04-22
申请号：BR9602624
申请日：1996-06-04
Applicant: MOTOROLA INC
Abstract: A unique method and apparatus modifies the load impedance at the output of a power amplifier by varying a voltage variable capacitor (VVC) (310) to maximize the efficiency of the power amplifier (304). A comparator (509) generates amplifier control signal (211) based upon a detected power output signal (216) and a reference signal. In addition to providing power control, the control signal is also coupled to a VVC circuit (506) to control the output impedance of the power amplifier. In an alternate embodiment, a separate VVC control signal (527) based upon a comparison of the power control signal and the battery voltage is coupled to a VVC. In another alternate embodiment, a second VVC can be coupled in parallel to the first VVC. The second VVC is preferably controlled by a signal (805) based upon the current in the power amplifier. Finally, an alternate embodiment incorporates a VVC circuit (506) at the input of the power amplifier to compensate for variations in input impedance to improve other power amplifier parameters such as IM, gain, output power and noise level.
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公开(公告)号：ZA964876B
公开(公告)日：1997-01-07
申请号：ZA964876
申请日：1996-06-07
Applicant: MOTOROLA INC
Inventor： KIM JIN DONG , CMKOVIC JAMES JOHN , KLOMSDORF ARMIN WERNER , PECKHAM DAVID SUTHERLAND
Abstract: A unique method and apparatus modifies the load impedance at the output of a power amplifier by varying a voltage variable capacitor (VVC) (310) to maximize the efficiency of the power amplifier (304). A comparator (509) generates amplifier control signal (211) based upon a detected power output signal (216) and a reference signal. In addition to providing power control, the control signal is also coupled to a VVC circuit (506) to control the output impedance of the power amplifier. In an alternate embodiment, a separate VVC control signal (527) based upon a comparison of the power control signal and the battery voltage is coupled to a VVC. In another alternate embodiment, a second VVC can be coupled in parallel to the first VVC. The second VVC is preferably controlled by a signal (805) based upon the current in the power amplifier. Finally, an alternate embodiment incorporates a VVC circuit (506) at the input of the power amplifier to compensate for variations in input impedance to improve other power amplifier parameters such as IM, gain, output power and noise level.
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公开(公告)号：GB2356095B
公开(公告)日：2002-02-13
申请号：GB0017433
申请日：2000-07-14
Applicant: MOTOROLA INC
Inventor： ALBERTH WILLIAM P , KLOMSDORF ARMIN WERNER , WINKELMANN LUKE EDWARD
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.
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公开(公告)号：GB2356093B
公开(公告)日：2001-12-12
申请号：GB0017401
申请日：2000-07-14
Applicant: MOTOROLA INC
Inventor： ALBERTH WILLIAM P , KLOMSDORF ARMIN WERNER , WINKELMANN LUKE EDWARD
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.
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Patent Agency Ranking
公开(公告)号：GB2356095A
公开(公告)日：2001-05-09
申请号：GB0017433
申请日：2000-07-14
Applicant: MOTOROLA INC
Inventor： ALBERTH WILLIAM P , KLOMSDORF ARMIN WERNER , WINKELMANN LUKE EDWARD
Abstract: A transmitter amplifying arrangement for linear modulation schemes is described, in which the signal in the power amplifier 118 is amplified as a constant envelope signal, so that efficient amplification may be used, eg class C. An impedance network 120 following the amplifier is then controlled to produce the desired amplitude modulation. A pre-distortion arrangement is also described.
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公开(公告)号：GB2356093A
公开(公告)日：2001-05-09
申请号：GB0017401
申请日：2000-07-14
Applicant: MOTOROLA INC
Inventor： ALBERTH WILLIAM P , KLOMSDORF ARMIN WERNER , WINKELMANN LUKE EDWARD
Abstract: An envelope following amplifier arrangement for a transmitter is described, in which an impedance network 120 connected to the output of the power amplifier 118 is controlled to follow the envelope and so improve the efficiency. A pre-distortion arrangement is also described.
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公开(公告)号：GB2352897A
公开(公告)日：2001-02-07
申请号：GB0017436
申请日：2000-07-14
Applicant: MOTOROLA INC
Inventor： KLOMSDORF ARMIN WERNER , ALBERTH WILLIAM P , WINKELMANN LUKE EDWARD
Abstract: A power amplifying circuit (300) with load adjust for control of adjacent and alternate channel power. A power amplifier (172) amplifies an input signal to produce an amplified signal. A variable impedance network (174) presents different impedances to the output of the power amplifier (172) responsive to a load control signal. A detector (180) provides an indication of a peak-to-average or difference ratio of the amplified signal. A controller (184) coupled to the detector (180) and the variable impedance network (174) produces the load control signal responsive to the indication of the peak-to-average ratio or difference.
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公开(公告)号：IT1285195B1
公开(公告)日：1998-06-03
申请号：ITRM960394
申请日：1996-06-05
Applicant: MOTOROLA INC
Abstract: A unique method and apparatus modifies the load impedance at the output of a power amplifier by varying a voltage variable capacitor (VVC) (310) to maximize the efficiency of the power amplifier (304). A comparator (509) generates amplifier control signal (211) based upon a detected power output signal (216) and a reference signal. In addition to providing power control, the control signal is also coupled to a VVC circuit (506) to control the output impedance of the power amplifier. In an alternate embodiment, a separate VVC control signal (527) based upon a comparison of the power control signal and the battery voltage is coupled to a VVC. In another alternate embodiment, a second VVC can be coupled in parallel to the first VVC. The second VVC is preferably controlled by a signal (805) based upon the current in the power amplifier. Finally, an alternate embodiment incorporates a VVC circuit (506) at the input of the power amplifier to compensate for variations in input impedance to improve other power amplifier parameters such as IM, gain, output power and noise level.
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公开(公告)号：ITRM960394A1
公开(公告)日：1997-12-05
申请号：ITRM960394
申请日：1996-06-05
Applicant: MOTOROLA INC
Abstract: A unique method and apparatus modifies the load impedance at the output of a power amplifier by varying a voltage variable capacitor (VVC) (310) to maximize the efficiency of the power amplifier (304). A comparator (509) generates amplifier control signal (211) based upon a detected power output signal (216) and a reference signal. In addition to providing power control, the control signal is also coupled to a VVC circuit (506) to control the output impedance of the power amplifier. In an alternate embodiment, a separate VVC control signal (527) based upon a comparison of the power control signal and the battery voltage is coupled to a VVC. In another alternate embodiment, a second VVC can be coupled in parallel to the first VVC. The second VVC is preferably controlled by a signal (805) based upon the current in the power amplifier. Finally, an alternate embodiment incorporates a VVC circuit (506) at the input of the power amplifier to compensate for variations in input impedance to improve other power amplifier parameters such as IM, gain, output power and noise level.
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