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1. 发明公开

EP0489081A4 GAIN/PHASE COMPENSATION FOR LINEAR AMPLIFIER FEEDBACK LOOP 失效
标题翻译：线性放大器反馈环路的增益/相位补偿
公开(公告)号：EP0489081A4
公开(公告)日：1992-10-14
申请号：EP90913028
申请日：1990-08-13
申请人： MOTOROLA, INC.
发明人： LEITCH, CLIFFORD, D.
IPC分类号： H04B1/04 , H03G3/20 , H04L27/01 , H04L27/20
CPC分类号： H03G3/3042 , H03F1/34 , H03F3/24 , H04B2001/0433
摘要： A gain/phase compensation method and apparatus for a linear amplifier feedback loop in a transmitter (100). The transmitter (100) includes an input (102 or 110), a linear amplifier (143), and a modulator (142), to provide a modulated carrier-frequency output signal. The transmitter also comprises a feedback detector (154), coupled to receive the output signal and also coupled to the input. The feedback detector (120) produces a detected baseband feedback signal and applies the feedback signal to the input. The transmitter (100) of the present invention further comprises stabilizing means (118 and 130), coupled to the input (102 or 110) and to the linear amplifier (143), for reducing the open-loop gain of the linear amplifier (143) to a value lower than one for all frequencies where the feedback loop causes the phase of the baseband input signal to shift by more than 180 degrees.

2. 发明公开

EP0466814A4 INTEGER DIVIDER CIRCUIT 失效
标题翻译：整数分频器电路
公开(公告)号：EP0466814A4
公开(公告)日：1993-02-24
申请号：EP90906531
申请日：1990-04-02
申请人： MOTOROLA INC.
发明人： OOMS, WILLIAM, J. , LEITCH, CLIFFORD, D. , DELGADO, RENE, M.
IPC分类号： G06F1/03 , G06F7/52 , G06F7/533 , G06F7/535
CPC分类号： G06F7/535 , G06F1/03 , G06F2207/5354 , G06F2207/5356
摘要： A divider circuit (100) for producing a quotient result (Q) within one cycle time is provided. The invention utilizes combinational circuitry for performing a division operation by computing a scaled reciprocal of the denominator (SRD) and multiplying the scaled output by a similarly scaled numerator. The denominator is scaled such that it falls within a predetermined range, and the reciprocal value may be looked up from a memory device such as a ROM (500). The output of the multiplier (SQ) may also be scaled in order to produce the desired result (Q). The resulting quotient has a controlled error over a wide range of numerator and denominator input values.

3. 发明公开

EP0400027A4 METHOD AND APPARATUS FOR QUADRATURE MODULATION 失效
标题翻译：方法和装置的调制方法
公开(公告)号：EP0400027A4
公开(公告)日：1991-10-23
申请号：EP89901689
申请日：1988-12-16
申请人： MOTOROLA, INC.
发明人： LEITCH, CLIFFORD, D.
IPC分类号： H04L27/36 , H03C3/40 , H03D7/16 , H04L27/12 , H04L27/20 , H04L27/34
CPC分类号： H04L27/362 , H03C3/403 , H03C2200/0029 , H03C2200/0058 , H03D7/161 , H03D7/165 , H04L27/3455 , H04L27/365
摘要： A quadrature amplitude modulation system utilizes two subcarrier signals (11, 12) each quadrature modulated with information signals (S1, S2, S3, S4) which are quadrature modulated onto the RF carrier (22). This provides a hole in the center of frequency spectrum, permitting carrier and bit sync signals can be provided in the center area of the signal spectrum.

4. 发明公开

EP0495921A4 STABILIZING CIRCUIT FOR FEEDBACK RF AMPLIFIER 失效
标题翻译：用于反馈射频放大器的稳定电路
公开(公告)号：EP0495921A4
公开(公告)日：1992-09-23
申请号：EP90917172
申请日：1990-10-10
申请人： MOTOROLA, INC.
发明人： LEITCH, CLIFFORD, D.
IPC分类号： H03F1/26 , H03C3/08 , H03F1/32 , H03F1/34 , H04L27/36
CPC分类号： H03F1/3282 , H03C3/08 , H03F1/3247 , H03F1/3276 , H03F1/3294 , H03F1/34 , H03F2200/102 , H03F2200/336 , H03F2200/57 , H04L27/368
摘要： A transmitter (100), with an inphase input (102) for receiving an inphase baseband input signal, and a quadrature input (112) for receiving a quadrature baseband input signal, comprises a modulator (130), coupled to the inphase and quadrature inputs, for modulating the inphase and quadrature baseband signals, to provide a modulated radio-frequency signal, and a linear amplifier (135), coupled to the modulator, for amplifying the modulated radio-frequency signal to produce an output signal. An oscillation detector is coupled to receive the output signal, for detecting oscillation, and for producing an error signal as a result of the oscillation. The transmitter also comprises circuitry (transmission gates 124, 126, 127, and 128) for reducing the open loop gain of the feedback loop, disposed between the inphase and quadrature inputs and the modulator. The circuitry for reducing the open loop gain reduces the open loop gain of the transmitter to less than one, in response to the error signal.

5. 发明公开

EP0434689A4 SYNCHRONOUS RECEIVER FOR MINIMUM SHIFT KEYING TRANSMISSION 失效
标题翻译：用于最小移位键控传输的同步接收器
公开(公告)号：EP0434689A4
公开(公告)日：1991-12-27
申请号：EP89906916
申请日：1989-05-22
申请人： MOTOROLA, INC.
发明人： LEITCH, CLIFFORD, D. , STEEL, FRANCIS, ROBERT
IPC分类号： H04L27/14 , H04L27/18 , H04L27/22 , G11C11/26
CPC分类号： H04L27/22
摘要： A receiver circuit recovers the phase of the carrier of a received MSK signal so that conventional synchronous detection techniques can be employed to demodulate the received signal. A quadrature receiver circuit (204-214) processes the received MSK signal to produce in-phase and quadrature phase baseband signals. These I-channel and Q-channel baseband signals are viewed as one signal which is expressed as a complex number; the I-channel forming the real part and the Q-channel forming the imaginary part. The baseband signal is multiplied (218 and 220) by odd and even orthogonal functions (222 and 224) and then integrated (226 and 227) over odd and even numbered two bit periods, respectively. The odd orthogonal function begins and ends on odd numbered two bit periods of the received MSK signal, while the even orthogonal function begins and ends on even numbered two bit periods. The result of the integration is a single complex number for each bit of the received signal. From each of these complex numbers, two supplementary angles are computed (228 and 229). A phase error algorithm (230) resolves which one of the two supplementary angles is the phase error between the carrier of the received MSK signal and the oscillator (208 or 302) of the quadrature circuit by selecting the angle that is closer to the phase error that was calculated for the previous bit.

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