公开(公告)号：US07839210B2

公开(公告)日：2010-11-23

申请号：US12248581

申请日：2008-10-09

申请人： Gilles Bas ,  Marc Battista

发明人： Gilles Bas ,  Marc Battista

IPC分类号： H03D1/00 ,  H03D1/18

CPC分类号： H03D1/00

摘要： A method and a circuit for detecting a radio-frequency signal, including at least one first MOS transistor with a channel of a first type, having its gate coupled to an input terminal capable of receiving said signal; a circuit for biasing the first transistor, capable of biasing it to a level lower than its threshold voltage; and a circuit for determining the average value of the current in the first transistor.

摘要翻译： 一种用于检测射频信号的方法和电路，包括具有第一类型的信道的至少一个第一MOS晶体管，其栅极耦合到能够接收所述信号的输入端; 用于偏置第一晶体管的电路，其能够将其偏置到低于其阈值电压的电平; 以及用于确定第一晶体管中的电流的平均值的电路。

公开(公告)号：US20060274857A1

公开(公告)日：2006-12-07

申请号：US11143250

申请日：2005-06-02

申请人： Lihu Chiu

发明人： Lihu Chiu

IPC分类号： H04L27/00

CPC分类号： H04L27/22 ,  H03D1/00 ,  H04L27/06

摘要： An RFID receiver uses digital down conversion to facilitate determination of the frequency of a radio frequency signal from an RFID tag and to facilitate demodulation of the signal. Two analog-to-digital converters can be configured to undersample a signal from the RFID tag. Adjacent pairs of samples can be used to determine the frequency of the radio frequency signal. The digital signal resulting from undersampling by one of the two analog-to-digital signals defines a frequency down converted signal that can be used for demodulation. Frequency down conversion facilitates the use of a field programmable gate array (FPGA) and/or a digital signal processor (DSP) for determination of the frequency and demodulation, thus eliminating costly analog components while increasing the flexibility of the receiver.

摘要翻译： RFID接收机使用数字下变频来促进来自RFID标签的射频信号的频率的确定并促进信号的解调。 两个模拟 - 数字转换器可以配置为对来自RFID标签的信号进行欠采样。 可以使用相邻的采样对来确定射频信号的频率。 由两个模拟 - 数字信号之一欠采样产生的数字信号定义了可用于解调的降频转换信号。 降频转换有利于使用现场可编程门阵列（FPGA）和/或数字信号处理器（DSP）来确定频率和解调，从而消除昂贵的模拟组件，同时增加接收机的灵活性。

公开(公告)号：US06985540B2

公开(公告)日：2006-01-10

申请号：US09985772

申请日：2001-11-06

申请人： Osamu Nishikido

发明人： Osamu Nishikido

IPC分类号： H03D1/24 ,  H04L27/14 ,  H04L27/16 ,  H04L27/22

CPC分类号： H03D1/00

摘要： An AM demodulator includes an APC detection circuit that compares phases of an AM-modulated input signal and a signal output from a VCO. However, the APC detection circuit multiples the two signals before their comparison. As a result, even if the phases of the input signal or the signal output from the VCO is shifted by 180 degrees, the result of comparison by the APC detection circuit is not influenced by the phase shift. Moreover, when a signal detected by the AM detection circuit is in a potential range showing over-modulation, operation of a PLL circuit is stopped.

摘要翻译： AM解调器包括APC检测电路，其比较AM调制输入信号和从VCO输出的信号的相位。 然而，APC检测电路在比较之前将两个信号相乘。 结果，即使输入信号的相位或从VCO输出的信号偏移了180度，APC检测电路的比较结果也不受相移的影响。 此外，当由AM检测电路检测到的信号处于表示过调制的电位范围时，停止PLL电路的动作。

公开(公告)号：US20050195023A1

公开(公告)日：2005-09-08

申请号：US11084216

申请日：2005-03-18

申请人： Admir Alihodzic

发明人： Admir Alihodzic

IPC分类号： H03D1/00 ,  H04L27/06

CPC分类号： H03D1/00 ,  H04L27/06

摘要： Method and a circuit arrangement for demodulating a digital amplitude-modulated radio signal, received using a reception device, having a carrier signal and a digital information signal impressed thereon. The radio signal is split into first and second signal components having a same polarization and opposite phases, and the first and second signal components are respectively inverted and then “ANDed”.

摘要翻译： 用于解调使用接收装置接收的数字幅度调制无线电信号的方法和电路装置，具有载波信号和印在其上的数字信息信号。 无线电信号被分成具有相同极化和相反相位的第一和第二信号分量，并且第一和第二信号分量分别被反转然后“与”。

公开(公告)号：US06748028B1

公开(公告)日：2004-06-08

申请号：US09571965

申请日：2000-05-16

申请人： Luigi Della Torre ,  Marco Ronchi ,  Andrea Vitali

发明人： Luigi Della Torre ,  Marco Ronchi ,  Andrea Vitali

IPC分类号： H03D124

CPC分类号： H03D1/00 ,  H04N5/455 ,  H04N21/4382

摘要： A digital AM demodulator, particularly for demodulating an input signal originating from a tuner, includes a first carrier generator for generating a first carrier signal which is not correlated with the input signal, and a multiplier for multiplying the first carrier signal by the input signal. Filters are arranged upstream and downstream of the multiplier for filtering undesired signals. The digital AM demodulator further includes a circuit for detecting a phase shift between a frequency of the input signal and a frequency of a local carrier signal. A correlation circuit correlates the first carrier signal with the input signal. The first carrier signal and the local carrier signal are mutually correlated, whereas the local carrier signal is not correlated with the input signal.

摘要翻译： 数字AM解调器，特别是用于解调来自调谐器的输入信号，包括用于产生与输入信号不相关的第一载波信号的第一载波发生器和用于将第一载波信号乘以输入信号的乘法器。 滤波器布置在乘法器的上游和下游，用于滤除不需要的信号。 数字AM解调器还包括用于检测输入信号的频率和本地载波信号的频率之间的相移的电路。 相关电路将第一载波信号与输入信号相关联。 第一载波信号和本地载波信号相互相关，而本地载波信号与输入信号不相关。

公开(公告)号：US5936462A

公开(公告)日：1999-08-10

申请号：US968113

申请日：1997-11-12

申请人： Akihiro Muraishi

发明人： Akihiro Muraishi

IPC分类号： H03D1/10 ,  H03D1/00 ,  H04L27/06

CPC分类号： H04L27/06 ,  H03D1/00

摘要： An amplitude-modulated carrier signal is demodulated by passage through a limiting amplifier that converts the amplitude-modulated carrier signal to a signal of constant amplitude, and also produces a received signal strength indicator signal. The received signal strength indicator signal is used as the demodulated signal.

摘要翻译： 幅度调制载波信号通过限幅放大器解调，该限幅放大器将调幅载波信号转换为恒幅信号，并产生接收信号强度指示信号。 接收到的信号强度指示信号用作解调信号。

公开(公告)号：US5465414A

公开(公告)日：1995-11-07

申请号：US265981

申请日：1994-06-27

申请人： Raymond W. Moskaluk ,  Nancy W. Nelson

发明人： Raymond W. Moskaluk ,  Nancy W. Nelson

IPC分类号： G01R23/14 ,  H03B21/00 ,  H03D1/00 ,  H03D7/00 ,  H03D9/06 ,  H03J1/00 ,  H04B1/26 ,  G01R23/16 ,  H04B17/00

CPC分类号： H03J1/0091 ,  H03B21/00 ,  H03D7/00 ,  H03D1/00 ,  H03D9/06

摘要： A method and apparatus for detecting a high frequency signal by down converting the high frequency signal to an intermediate frequency signal by mixing the high frequency signal with the harmonics of a minimal number of local oscillator frequency signals chosen so that at least one harmonic of at least one of the local oscillator frequency signals will convert any high frequency signal in a given frequency range to an intermediate signal in another given frequency range, and applying the result to detectors sensitive to signals in the intermediate frequency range.

摘要翻译： 一种用于通过将高频信号与选择的最小数量的本地振荡器频率信号的谐波混合来将高频信号下变频为中频信号来检测高频信号的方法和装置，使得至少一个谐波至少 本地振荡器频率信号之一将将给定频率范围内的任何高频信号转换为另一给定频率范围内的中间信号，并将结果应用于对中频范围信号敏感的检测器。

公开(公告)号：US5440588A

公开(公告)日：1995-08-08

申请号：US36687

申请日：1993-03-25

申请人： Junzo Murakami

发明人： Junzo Murakami

IPC分类号： H04L25/08 ,  H03D1/00 ,  H03M13/25 ,  H03M13/41 ,  H03M13/51 ,  H04L25/03 ,  H03D1/06

CPC分类号： H03M13/6502 ,  H03D1/00 ,  H03M13/3961 ,  H03M13/41 ,  H04L25/03197

摘要： A maximum likelihood sequence estimation capable of reducing an amount of real time calculations involved and improving a high speed follow up characteristic. N-dimensional vectors corresponding to all possible transmission sequence candidates of a prescribed length, which are pre-calculated according to a prescribed definition, are stored in a memory. Then, an estimated received signal for each one of the branches at the present sampling time is obtained by calculating an inner product of one of the N-dimensional vectors stored in the memory corresponding to each transmission sequence candidate resulting from each one of the branches reaching to each state at the present sampling time with the N-dimensional received signal vector for the present sampling time obtained from at least N received signals for at least N previous sampling times. The maximum likelihood sequence can be estimated as a survivor path for each state at the present sampling time according to this estimated received signal as usual.

摘要翻译： 最大似然序列估计能够减少所涉及的实时计算量并提高高速跟踪特性。 对应于根据规定的定义预先计算的规定长度的所有可能的传输序列候选的N维向量被存储在存储器中。 然后，通过计算存储在与每个分支到达的每个传输序列候选者相对应的存储器中的存储器中的一个N维向量的内积，得到当前采样时刻的每个分支的估计接收信号 在至少N个以前的采样时间从至少N个接收信号获得的当前采样时间的N维接收信号矢量在当前采样时间到每个状态。 根据该估计的接收信号，最大似然序列可以被估计为在当前采样时间的每个状态的幸存路径。

公开(公告)号：US5115201A

公开(公告)日：1992-05-19

申请号：US628266

申请日：1990-12-17

申请人： Mark D. Asplund

发明人： Mark D. Asplund

IPC分类号： H03D1/00 ,  H03D1/24

CPC分类号： H03D1/00 ,  H03D1/24

摘要： A digital demodulator utilizes voltage to frequency converters, digital counters and a computer to combine demodulation and analog to digital conversion into one step, therefore providing for in-phase and quadrature demodulation of amplitude modulated double sideband suppressed carrier signals. Accleration sinusoidal signals and phase reference pulses are input to a voltage to frequency converter and counter board which interfaces to a computer where the signals are demodulated using a digital demodulation scheme.

摘要翻译： 数字解调器利用电压到频率转换器，数字计数器和计算机将解调和模数转换组合成一个步骤，从而提供幅度调制双边带抑制载波信号的同相和正交解调。 加速正弦信号和相位参考脉冲被输入到电压到频率转换器和计数器板，其与使用数字解调方案解调信号的计算机连接。

公开(公告)号：US5073904A

公开(公告)日：1991-12-17

申请号：US354918

申请日：1989-05-22

申请人： Shigeki Nakamura ,  Yasufumi Takahashi

发明人： Shigeki Nakamura ,  Yasufumi Takahashi

IPC分类号： H04L27/00 ,  H03D1/00 ,  H04L7/00 ,  H04L7/02 ,  H04L27/22 ,  H04L27/38

CPC分类号： H04L7/0029 ,  H03D1/00

摘要： Disclosed is a digital demodulation technique in which a reception modulated-wave signal is converted into a digital signal in synchronism with a sampling frequency, whereafter carrier regeneration/detection is carried out upon the digital signal to thereby output a detection signal. Then, the detection signal is subject to interpolation and resampling on the basis of a clock frequency established asynchronously with and independently of the sampling frequency, so that a timing component is extracted from the detection signal in synchronism with the clock frequency to thereby output a reception data. In the digital demodulation technique, since the sampling frequency and the clock frequency are established asynchronously with and independently of each other, jitter or the like produced in clock regeneration do not affect the carrier regeneration/detection. Consequently, noiseless reception data with little jitters can be regenerated.

摘要翻译： 公开了一种数字解调技术，其中接收调制波信号与采样频率同步地转换为数字信号，之后对数字信号执行载波再生/检测，从而输出检测信号。 然后，基于与采样频率异步建立的时钟频率对检测信号进行内插和重采样，从而与时钟频率同步地从检测信号中提取定时分量，从而输出接收 数据。 在数字解调技术中，由于采样频率和时钟频率彼此异步地建立并且彼此独立地建立，所以在时钟再生中产生的抖动等不影响载波再生/检测。 因此，可以再生具有小抖动的无噪声接收数据。