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公开(公告)号：CA2176551A1
公开(公告)日：1996-12-08
申请号：CA2176551
申请日：1996-05-14
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：MX9801327A
公开(公告)日：1998-08-30
申请号：MX9801327
申请日：1998-02-18
Applicant: MOTOROLA INC
Inventor： VLAHOS CONSTANTINE , PECKHAM DAVID SUTHERLAND , SKUTTA FRANK ROBERT
Abstract: Un método y aparato permiten que un dispositivo de comunicacion (100) opere en multiples bandas, tal como bandas de GSM de 900 MHz, y DC8 de 1800 MHz, y DCs de 1900 MHz, al eliminar la necesidad de un mezclador para cada banda. En un radioteléfono de GSM/DCS 1800 de doble banda, por ejemplo, las frecuencias de inyeccion del oscilador local (LO) para ambas bandas de GSM y de DCS se proporcionan a un mezclador (234) a través del uso de filtros de combinacion (222, 246). De esta manera, los requerimientos de transmision en duplex y acoplamiento de la entrada del mezclador se simplifican y las pérdidas de señal se minimizan. Los puertos de salida comun del filtro de combinacion de RX/LO de GSM y el filtro de combinacion de RX/LO de DCS se transmiten en duplex a la entrada del mezclador. También, el acoplamiento de impedancia de entrada del mezclador se diseña para acoplar la impedancia para las señales recibidas en cada banda, así como para proporcionar un desvío de RF en la frecuencia de IF. El acoplamiento en la salida del mezclador se diseña para acoplar la impedancia del filtro de IF y proporciona una impedancia baja a las frecuencias de entrada de RF. Finalmente, también se describe un radioteléfono de triple banda.
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公开(公告)号：DE19806096A1
公开(公告)日：1998-08-27
申请号：DE19806096
申请日：1998-02-14
Applicant: MOTOROLA INC
Inventor： VLAHOS CONSTANTINE , PECKHAM DAVID SUTHERLAND , SKUTTA FRANK ROBERT
IPC: H04B1/40 , H03D7/12 , H03J1/00 , H04B1/26 , H04B1/44 , H04Q7/20 , H04Q7/32 , H04B7/005 , H04B1/18 , G08C17/02 , G06F15/00
Abstract: A method and apparatus enables a communication device (100) to operate in multiple bands, such as GSM 900 MHz, DCS 1800 MHz, and DCS 1900 MHz bands, by eliminating the need for a mixer for each band. In a dual band GSM/DCS 1800 radiotelephone, for example, the local oscillator (LO) injection frequencies for both GSM and DCS bands are provided to a mixer (234) through the use of combination filters (222, 246). Thus, the duplexing and matching requirements to the mixer input are simplified and the signal losses are minimized. The common output ports of the GSM RX/LO combination filter and DCS RX/LO combination filter are duplexed to the input of the mixer. Also, the input impedance matching of the mixer is designed to match the impedance for the received signals in each band, as well as provide an RF trap at the IF frequency. The match at the output of the mixer is designed to match the impedance of the IF filter and provides a low impedance to RF input frequencies. Finally, a tri-band radiotelephone is also described.
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公开(公告)号：GB2322491A
公开(公告)日：1998-08-26
申请号：GB9801264
申请日：1998-01-21
Applicant: MOTOROLA INC
Inventor： VLAHOS CONSTANTINE , PECKHAM DAVID SUTHERLAND , SKUTTA FRANK ROBERT
Abstract: A method and apparatus enables a communication device Fig 1 to operate in multiple bands, such as GSM 900 MHz, DCS 1800 MHz, and PCS 1900 MHz bands, by eliminating the need for a mixer for each band. In a dual band GSM/DCS 1800 radiotelephone, for example, the local oscillator (LO) injection frequencies for both GSM and DCS bands are provided to a mixer (234) through the use of combination filters(222, 246). Thus, the duplexing and matching requirements to the mixer input are simplified and the signal losses are minimized. The common output ports of the GSM RX/LO combination filter and DCS RX/LO combination filter are duplexed to the input of the mixer. Also, the input impedance matching of the mixer is designed to match the impedance for the received signals in each band, as well as provide an RF trap at the IF frequency. The match at the output of the mixer is designed to match the impedance of the IF filter and provides a low impedance to RF input frequencies. Finally, a tri-band radiotelephone is also described.
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公开(公告)号：GB2301964A
公开(公告)日：1996-12-18
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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Patent Agency Ranking
公开(公告)号：GB2322491B
公开(公告)日：2000-03-22
申请号：GB9801264
申请日：1998-01-21
Applicant: MOTOROLA INC
Inventor： VLAHOS CONSTANTINE , PECKHAM DAVID SUTHERLAND , SKUTTA FRANK ROBERT
Abstract: A method and apparatus enables a communication device (100) to operate in multiple bands, such as GSM 900 MHz, DCS 1800 MHz, and DCS 1900 MHz bands, by eliminating the need for a mixer for each band. In a dual band GSM/DCS 1800 radiotelephone, for example, the local oscillator (LO) injection frequencies for both GSM and DCS bands are provided to a mixer (234) through the use of combination filters (222, 246). Thus, the duplexing and matching requirements to the mixer input are simplified and the signal losses are minimized. The common output ports of the GSM RX/LO combination filter and DCS RX/LO combination filter are duplexed to the input of the mixer. Also, the input impedance matching of the mixer is designed to match the impedance for the received signals in each band, as well as provide an RF trap at the IF frequency. The match at the output of the mixer is designed to match the impedance of the IF filter and provides a low impedance to RF input frequencies. Finally, a tri-band radiotelephone is also described.
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公开(公告)号：MX9801326A
公开(公告)日：1998-08-30
申请号：MX9801326
申请日：1998-02-18
Applicant: MOTOROLA INC
Inventor： PECKHAM DAVID SUTHERLAND
Abstract: Un VCO de transmisor (204) incluye nodos para recibir un voltaje selector de banda para alterar la capacitancia del emisor base de un transistor a fin de permitir que el VCO actue como un oscilador en la banda apropiada, y para alterar la capacitancia del resonador a fin de cambiar la frecuencia resonante del oscilador. El método y aparato permite la oscilacion en bandas de diferente frecuencia para los dispositivos de comunicacion de doble modo.
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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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公开(公告)号：GB2347292B
公开(公告)日：2001-04-18
申请号：GB0003945
申请日：2000-02-18
Applicant: MOTOROLA INC
Inventor： PECKHAM DAVID SUTHERLAND , DING DAVID Z , SKUTTA FRANK ROBERT , JOHNSON JR ROBERT M
Abstract: A multiple frequency band receiver (102) receives at least two frequency bands that are close but not adjacent. A first bandpass filter (304) passes signals in the first frequency band. A second bandpass filter (306) passes signals in the second frequency band. The first and second filters each attenuate signals between the first and second frequency band to at least a first level so as to provide selectivity in the frequency range between the first and second frequencies to prevent the signals between these frequency bands from being further processed by the communication device. A third filter (322) coupled to first and second filters passes signals in both the first and second frequency band and attenuates signals above the pass band of the higher of the first and second filters and below the lower of the first and second filters.
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