公开(公告)号：US09380389B2

公开(公告)日：2016-06-28

申请号：US14023350

申请日：2013-09-10

Applicant: NXP B.V.

Inventor： Temujin Gautama

IPC: H04H20/48 ,  H04R5/04 ,  H04H40/72 ,  H04L25/03

CPC classification number: H04R5/04 ,  H04H40/72 ,  H04L25/03159

Abstract: The invention provides an audio signal processing system in which a magnitude spectrum of a frequency domain audio signal is processed based on a measure of multipath interference. The processing keeps the magnitude spectrum approximately fixed during periods of multipath interference, for example by replacing it with a temporally smoothed version of the magnitude spectrum. The magnitude spectrum (processed if required) and the phase spectrum are combined to derive a frequency domain output, which is transformed to the time domain.

Abstract translation: 本发明提供一种音频信号处理系统，其中基于多路径干扰的测量来处理频域音频信号的幅度谱。 该处理在多径干扰期间保持幅度谱近似固定，例如用幅度谱的时间平滑版本代替它。 幅度谱（如果需要处理）和相位频谱被组合以导出频域输出，其被转换到时域。

公开(公告)号：US20150326330A1

公开(公告)日：2015-11-12

申请号：US14699662

申请日：2015-04-29

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC ,  KATHREIN AUTOMOTIVE NORTH AMERICA, INC.

Inventor： TIMOTHY J. TALTY ,  GREGG R. KITTINGER ,  ANDREAS FUCHS ,  ELIAS GHAFARI

IPC: H04H40/72

CPC classification number: H04H40/72 ,  H01Q1/3208 ,  H01Q5/321 ,  H04B1/18

Abstract: An AM/FM radio system for a vehicle that is selectively impedance matched to the particular tuned frequency of interest so that noise received by other frequencies does not affect the received signal. The radio system includes an HMI allowing a user to select an AM or FM radio station and a radio tuner responsive to a signal from the HMI identifying the selected radio station. The tuner tunes the radio system to the radio station, and provides a signal to the HMI identifying the radio station. The HMI places a message on a vehicle bus identifying the radio station that the radio tuner is tuned to. An antenna controller receives the message from the vehicle bus to selectively control an impedance matrix to provide impedance matching for the selected radio station frequency. The antenna controller also selectively tunes antenna radiating elements to the particular tuned frequency.

Abstract translation: 用于车辆的AM / FM无线电系统，其选择性地阻抗匹配于感兴趣的特定调谐频率，使得由其他频率接收的噪声不影响接收的信号。 无线电系统包括允许用户选择AM或FM无线电台的HMI，以及响应于来自HMI的信号识别所选择的无线电台的无线电调谐器。 调谐器将无线电系统调谐到无线电台，并向HMI识别广播电台提供信号。 HMI在车辆总线上放置一条消息，标识无线电调谐器调谐到的无线电台。 天线控制器从车辆总线接收消息以选择性地控制阻抗矩阵以提供所选无线电台频率的阻抗匹配。 天线控制器还选择性地将天线辐射元件调谐到特定的调谐频率。

公开(公告)号：US09130683B2

公开(公告)日：2015-09-08

申请号：US13171589

申请日：2011-06-29

Applicant: Sriram Murali ,  Aravind Ganesan

Inventor： Sriram Murali ,  Aravind Ganesan

IPC: H03G3/00 ,  H04H40/72 ,  H04R5/00 ,  H04B1/10 ,  H04H40/45

CPC classification number: H04H40/45 ,  H04B1/10 ,  Y10T29/49117

Abstract: An electronic circuit (100) for use in a wireless receiver (1720). The circuit (100) includes an audio demodulator (15), an audio envelope portion (35) operable to deliver an audio envelope signal, a high pass filter (38) coupled between the audio demodulator (15) and the audio envelope portion (35), a volume control (25) fed by the audio demodulator (15) and operable to provide a controllable audio signal output, and a controller (45) responsive to the audio envelope portion (35) to provide an attenuation control to the volume control (25). Other circuits, receivers, processes of operation, processes of manufacture, and processes of testing are disclosed.

Abstract translation: 一种用于无线接收机（1720）中的电子电路（100）。 电路（100）包括音频解调器（15），可操作以传送音频包络信号的音频包络部分（35），耦合在音频解调器（15）和音频信封部分（35）之间的高通滤波器 ），由音频解调器（15）馈送并且可操作以提供可控音频信号输出的音量控制（25），以及响应于音频包络部分（35）向音量控制器提供衰减控制的控制器（45） （25）。 公开了其他电路，接收器，操作过程，制造过程和测试过程。

公开(公告)号：US5661810A

公开(公告)日：1997-08-26

申请号：US522314

申请日：1995-08-25

Applicant: Djahanyar Chahabadi ,  Matthias Herrmann ,  Lothar Vogt ,  Jurgen Kaesser

Inventor： Djahanyar Chahabadi ,  Matthias Herrmann ,  Lothar Vogt ,  Jurgen Kaesser

IPC: H03H17/04 ,  H03H17/02 ,  H04B1/10 ,  H04B1/16 ,  H04B1/26 ,  H04B1/64 ,  H04H1/00 ,  H04H20/57 ,  H04H40/63 ,  H04H40/72 ,  H04H5/00

CPC classification number: H04H40/63 ,  H04H40/72 ,  H04H20/57

Abstract: The circuit arrangement includes a first low-pass filter (2) for filtering an input signal (H3) proportional to the strength of a received radio signal; a second low-pass filter (3) for filtering the input signal (H3); a first weighting circuit (7) for weighting the first low-pass filter output signal with first coefficients to form a first weighted output signal; a circuit device for forming a masking signal for reducing stereo channel isolation from the first weighted output signal; a second weighting circuit (5) for forming a second weighted output signal weighted with second coefficients from the first low-pass filter output signal or the second low-pass filter output signal according to a switching signal (DD2) indicative of interference in the audio signals; a switch device (4) for selecting the first low-pass filter output signal for weighting in the second weighting circuit means (5) when no interference is indicated by the switching signal (DD2) and the second low-pass filter output signal for weighting in the second weighting circuit means (5) when interference is indicated by the switching signal (DD2); and a circuit device for forming a masking signal for damping the audio signal from the second weighted output signal.

Abstract translation: PCT No.PCT / DE94 / 00321 Sec。 371日期1995年8月25日 102（e）日期1995年8月25日PCT 1994年3月22日PCT公布。 公开号WO94 / 22229 日期1995年9月29日该电路装置包括：第一低通滤波器（2），用于对与接收的无线电信号的强度成正比的输入信号（H3）进行滤波; 用于对输入信号（H3）进行滤波的第二低通滤波器（3）; 第一加权电路（7），用于利用第一系数对第一低通滤波器输出信号进行加权，以形成第一加权输出信号; 电路装置，用于形成用于减少立体声信道隔离的屏蔽信号与第一加权输出信号; 第二加权电路（5），用于根据指示音频中的干扰的切换信号（DD2），从第一低通滤波器输出信号或第二低通滤波器输出信号形成用第二系数加权的第二加权输出信号 信号; 开关装置（4），用于当没有由开关信号（DD2）指示干扰和用于加权的第二低通滤波器输出信号时，在第二加权电路装置（5）中选择用于加权的第一低通滤波器输出信号 在第二加权电路装置（5）中，当由切换信号（DD2）指示干扰时; 以及电路装置，用于形成用于阻尼来自第二加权输出信号的音频信号的屏蔽信号。

公开(公告)号：US4694500A

公开(公告)日：1987-09-15

申请号：US834980

申请日：1986-02-28

Applicant: Satoru Tazaki ,  Yasuhiro Yoshioka ,  Kiyoshi Amazawa

Inventor： Satoru Tazaki ,  Yasuhiro Yoshioka ,  Kiyoshi Amazawa

IPC: H04B1/10 ,  H04B1/16 ,  H04H1/00 ,  H04H40/72 ,  H04H5/00

CPC classification number: H04H40/72 ,  H04B1/1027 ,  H04B1/1676

Abstract: A high-cut and high-blend control voltage generating circuit for activating a noise reduction circuit of an FM stereo receiver is configured to be simply responsive to multipath noises and never to plug noises. A changing and discharging circuit in the control voltage circuit may have a relatively long charging time constant, and the voltage control circuit may be configured to be simply responsive to multipath noises above a predetermined level. Thus the circuit is much less liable to operate erroneously.

Abstract translation: 用于激活FM立体声接收机的降噪电路的高切高混合控制电压发生电路被配置为简单地响应于多路径噪声，并且从不插入噪声。 控制电压电路中的改变和放电电路可以具有相对长的充电时间常数，并且电压控制电路可以被配置为简单地响应于高于预定电平的多径噪声。 因此，该电路不太容易错误地操作。

公开(公告)号：US4489430A

公开(公告)日：1984-12-18

申请号：US408993

申请日：1982-08-17

Applicant: Kohji Ishida ,  Tatsuo Numata ,  Tadashi Noguchi

Inventor： Kohji Ishida ,  Tatsuo Numata ,  Tadashi Noguchi

IPC: H03D1/22 ,  H03D3/04 ,  H04H1/00 ,  H04H40/45 ,  H04H40/72 ,  H04H5/00

CPC classification number: H04H40/72 ,  H03D1/2227 ,  H03D3/04

Abstract: A pulse position modulated (PPM) signal is derived from an input FM signal, and first and second switching signals are derived which are opposite in phase and correspond to alternating half cycles of the PPM signal. First and second opposite phase subcarrier signals are derived synchronized to the pilot signal in the input FM signal, and various combinations of the switching and subcarrier signals are multiplied together and the multiplication products combined to obtain left and right channel outputs.

Abstract translation: 从输入FM信号导出脉冲位置调制（PPM）信号，导出与相位相反并对应于PPM信号的交替半周期的第一和第二切换信号。 导出与输入FM信号中的导频信号同步的第一和第二相反相位副载波信号，并将切换和副载波信号的各种组合相乘在一起，乘积合成以获得左右声道输出。

公开(公告)号：US4244056A

公开(公告)日：1981-01-06

申请号：US19840

申请日：1979-03-12

Applicant: Masanori Hamada ,  Sueji Kawaguchi

Inventor： Masanori Hamada ,  Sueji Kawaguchi

IPC: H03G5/18 ,  H04B1/10 ,  H04B1/16 ,  H04H1/00 ,  H04H40/72 ,  H04B15/00

CPC classification number: H04H40/72 ,  H03G5/18 ,  H04B1/1669

Abstract: In an FM stereo-receiver, a noise reduction circuit includes a by-pass circuit connected between the output of an FM detector and an earth potential point, the time constant of which is controlled to continuously vary the frequency characteristic at a path from the FM detector to an MPX circuit, thereby greatly reducing a high frequency noise inherent therein.

Abstract translation: 在FM立体声接收机中，噪声降低电路包括连接在FM检测器的输出端和接地电位点之间的旁路电路，其时间常数被控制以连续地改变来自FM的路径上的频率特性 检测器到MPX电路，从而大大降低其中固有的高频噪声。

公开(公告)号：US4076963A

公开(公告)日：1978-02-28

申请号：US788497

申请日：1977-04-18

Applicant: Seijiro Fujie ,  Susumu Yokoyama, deceased ,  by Toshikazu Yokoyama, administrator

Inventor： Seijiro Fujie ,  Susumu Yokoyama, deceased ,  by Toshikazu Yokoyama, administrator

IPC: H03D1/22 ,  H04B1/10 ,  H04H1/00 ,  H04H40/72 ,  H04H5/00

CPC classification number: H04H20/48 ,  H03D1/2236 ,  H04H40/72

Abstract: A pilot signal cancelling circuit for an FM multiplex demodulator wherein the amplitude of the cancelling signal tracks that of the pilot signal contained in or mixed into the composite signal. The amplified composite signal is synchronously detected with the fixed amplitude 19 KHz pilot signal extracted by a phase lock loop 2, and the detector output is filtered to remove high frequency components and then converted to a current variation in a d.c. amplifier 13. The output of the latter is fed to a current controlled attenuator 14 together with the fixed amplitude pilot signal, and the level adjusted attenuator output is then inverted, divided into left and right channel components by the 38 KHz sub-carrier signals, and fed to adders in the multiplex demodulator outputs to cancel the pilot signal components therein.

Abstract translation: 一种用于FM多路复用解调器的导频信号消除电路，其中抵消信号的幅度跟踪包含在或混合到复合信号中的导频信号的幅度。 放大的复合信号与由锁相环2提取的固定幅度19KHz的导频信号同步检测，滤波器输出被滤波以去除高频分量，然后转换为电流变化。 放大器13.后者的输出与固定振幅导频信号一起馈送到电流控制衰减器14，然后将电平调节的衰减器输出反相，通过38KHz子载波信号被分成左和右声道分量， 并馈送到多路解调器输出中的加法器以消除其中的导频信号分量。

公开(公告)号：US4069398A

公开(公告)日：1978-01-17

申请号：US719629

申请日：1976-09-01

Applicant: Seijiro Fujie

Inventor： Seijiro Fujie

IPC: H03D1/22 ,  H04B1/16 ,  H04H1/00 ,  H04H40/72 ,  H04H5/00

CPC classification number: H04H40/72 ,  H03D1/2227 ,  H04B1/1646 ,  H03D2200/0086

Abstract: Unwanted pilot signal components in the "L" and "R" outputs of a stereophonic FM multiplex demodulator are cancelled by inverting the 19KHz pilot signal, separately multiplying or gating it with the opposite phase 38KHz subcarrier signals, and adding the multiplier or gate outputs to the "L" and "R" demodulator outputs. The multiplication produces signals equal in amplitude but opposite in phase to the contaminating pilot signal components, whereby the latter are effectively cancelled by the addition function.

Abstract translation: 立体声FM多路复用解调器的“L”和“R”输出中的不需要的导频信号分量通过将19KHz导频信号反相，分别乘以相反相位38KHz副载波信号，或将乘法器或门输出相加 “L”和“R”解调器输出。 乘法产生幅度相等但信号与污染导频信号分量相反的信号，从而后者被加法函数有效地消除。

公开(公告)号：US20220209807A1

公开(公告)日：2022-06-30

申请号：US17530158

申请日：2021-11-18

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Jaiganesh Balakrishnan

IPC: H04B1/12 ,  H04B1/16 ,  H04H40/72 ,  H04B17/318 ,  H04B17/20 ,  H04B17/336 ,  H04B1/10

Abstract: A wireless receiver (10) includes a down converter module (210) operable to deliver a signal having a signal bandwidth that changes over time, a dynamically controllable filter module (200) having a filter bandwidth and fed by said down converter module (210), and a measurement module (295) operable to at least approximately measure the signal bandwidth, said dynamically controllable filter module (200) responsive to said measurement module (295) to dynamically adjust the filter bandwidth to more nearly match the signal bandwidth as it changes over time, whereby output from said filter module (200) is noise-reduced. Other wireless receivers, electronic circuits, and processes for their operation are disclosed.