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81. 发明授权

US5999574A Digital filter system, carrier reproduction circuit using the digital filter system, and demodulation circuit using the carrier reproduction circuit 失效
标题翻译：数字滤波器系统，使用数字滤波器系统的载波再现电路和使用载波再现电路的解调电路
公开(公告)号：US5999574A
公开(公告)日：1999-12-07
申请号：US814879
申请日：1997-03-13
申请人： Weimin Sun , Hirofumi Yamauchi , Michio Nakajima
发明人： Weimin Sun , Hirofumi Yamauchi , Michio Nakajima
IPC分类号： H04B1/30 , H04L27/00 , H04L27/14
CPC分类号： H04L27/0014 , H04B1/30 , H04B1/302 , H04L2027/0069
摘要： An input analog signal is sampled at a sampling frequency f.sub.s, which is four times a carrier frequency f.sub.c. A demultiplexer 11 outputs supplied data to four systems sequentially, and generates four zero carriers whose frequencies and amplitudes are equal to each other, with only the phases being different. The delay circuits 12 to 15 delay each one of the zero carriers, and supply delayed signals to adaptive filters 16 to 19. Data output from the four adaptive filters 16 to 19 are selected by a multiplexer 22, and the multiplexer 22 outputs the selected signals as a single signal. The difference between a first zero carrier and an output signals of the first adaptive filter 16 is obtained, and tap coefficients of the adaptive filters 16 to 19 are controlled in accordance with an LMS algorithm based on the difference. A signal output by the multiplexer 22 is output as a reproduced carrier.
摘要翻译：输入模拟信号以采样频率fs进行采样，采样频率fs是载波频率fc的四倍。解复用器11将提供的数据顺序地输出到四个系统，并且产生四个零载波，其频率和幅度彼此相等，只有相位不同。延迟电路12至15延迟零载波中的每一个，并将延迟的信号提供给自适应滤波器16至19.从多路复用器22选择从四个自适应滤波器16至19输出的数据，并且多路复用器22输出所选择的信号作为单个信号。获得第一自适应滤波器16的第一零载波和输出信号之间的差异，并且根据基于该差的LMS算法来控制自适应滤波器16至19的抽头系数。由复用器22输出的信号作为再现载波输出。

82. 发明授权

US5831488A Digital phase modulator formed with a fixed-point digital signal processor 失效
标题翻译：数字相位调制器用定点数字信号处理器形成
公开(公告)号：US5831488A
公开(公告)日：1998-11-03
申请号：US801728
申请日：1996-06-27
申请人： Michio Nakajima , Weimin Sun
发明人： Michio Nakajima , Weimin Sun
IPC分类号： H03H17/02 , H03C3/00 , H04L27/20
CPC分类号： H04L27/2092
摘要： Data from an A/D converter is supplied to a fixed-point DSP. The fixed-point DSP adjusts the level of the data x so that computed results do not exceed .+-.1. In succession, for the i-th data x.sub.i, the fixed-point DSP computes cos .pi..multidot.x.sub.i when i=1, 5, . . . , -sin .pi..multidot.x.sub.i when i=2, 6, . . . , -cos .pi..multidot.x.sub.i when i=3, 7, . . . and sin .pi..multidot.x.sub.i when i=4, 8, . . . and outputs a digital phase modulated signal y(t) by outputting the computed results in order. Trigonometrical functions are computed by expanding them to a series so that the intermediate computed results do not exceed .+-.1.
摘要翻译：来自A / D转换器的数据被提供给定点DSP。定点DSP调整数据x的电平，以便计算结果不超过+/- 1。接下来，对于第i个数据xi，当i = 1,5时，定点DSP计算cos pi xxi。。。当i = 2,6时，-sin pi xxi。。。，当i = 3,7时，-cos pi xxi。。。当i = 4,8时，sin pi xxi。。。并且通过按顺序输出计算结果来输出数字相位调制信号y（t）。通过将三角函数扩展为一系列来计算，以便中间计算结果不超过+/- 1。

83. 发明授权

US5654909A 90-degree digital phase shift network and linearizer using all-pass digital filters 失效
标题翻译： 90度数字移相网络和线性化采用全通数字滤波器
公开(公告)号：US5654909A
公开(公告)日：1997-08-05
申请号：US220430
申请日：1994-03-30
申请人： Weimin Sun
发明人： Weimin Sun
IPC分类号： H03H17/08 , G06F17/10
CPC分类号： H03H17/08
摘要： A 90-degree digital phase shift network includes at least two all-pass digital filters which have a phase difference of 90 degrees therebetween. These digital filters are adapted to receive the same signal. Each of the all-pass digital filters has phase characteristics .theta.(.omega.) given by ##EQU1## where T represents a sampling period, P.sub.i a real number indicative of a filter coefficient, .omega. the angular frequency, m a weight variable, n'=n/2 (n=even number), n'=(n+1)/2 (n=odd number), n an order of a 90-degree digital PSN, m being a positive value other than 1, and satisfying .vertline.2m.omega..vertline./.vertline.P.sub.i .vertline.
摘要翻译： 90度数字相移网络包括至少两个在其间具有90度相位差的全通数字滤波器。这些数字滤波器适于接收相同的信号。每个全通数字滤波器具有由给出的相位特性theta（ω），其中T表示采样周期，Pi表示滤波器系数的实数，ω是角频率，ma权重变量，n'= n / 2（n =偶数），n'=（n + 1）/ 2（n =奇数），n为90度数字PSN的顺序，m为除1以外的正值，满足| 2m 当omega T足够低于1时，omega | / | Pi | <1，而当omega T基本上等于pi时，满足|-PiωT2 | / 2m <1。

84. 发明授权

US5555453A Radio communication system 失效
标题翻译：无线通信系统
公开(公告)号：US5555453A
公开(公告)日：1996-09-10
申请号：US406661
申请日：1995-03-20
申请人： Shigeki Kajimoto , Weimin Sun
发明人： Shigeki Kajimoto , Weimin Sun
IPC分类号： H04B1/26 , H04B1/10 , H04B1/28 , H04B1/06 , H04B7/00
CPC分类号： H04B1/28
摘要： A CW (Continuous Wave) radio frequency signal converted to an IF (Intermediate Frequency) signal is mixed with a local oscillator signal by an IF mixer, and the obtained signal is converted to a digital signal by an ADC (Analog-to-Digital Converter). A digital bandpass filter passes only the target component in the output of the ADC. The passed IF signal is demodulated by a digital demodulator, and the demodulated signal is converted to an analog signal before being output as a sound. When pitch control to increase the reception pitch by .DELTA.f is instructed, an MPU (Microprocessor Unit) alters the frequency of the local oscillator signal by .DELTA.f as well as the center frequency of the digital bandpass filter by .DELTA.f, so that the center frequency of the input signal to a narrow-band filter coincides with the center frequency of the digital bandpass filter.
摘要翻译：通过IF混频器将转换成IF（中频）信号的CW（连续波）射频信号与本地振荡器信号混合，并且所获得的信号由ADC（模数转换器）转换成数字信号）。数字带通滤波器仅通过ADC输出中的目标分量。通过的IF信号由数字解调器解调，解调后的信号在作为声音输出之前被转换为模拟信号。指示通过DELTA f增加接收音调的音高控制时，MPU（微处理器单元）通过DELTA f和DELTA f将数字带通滤波器的中心频率改变为本地振荡器信号的频率，使得中心到窄带滤波器的输入信号的频率与数字带通滤波器的中心频率一致。

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