公开(公告)号：WO1997043609A1

公开(公告)日：1997-11-20

申请号：PCT/US1997008095

申请日：1997-05-13

Applicant: ALLIEDSIGNAL INC.

Inventor： ALLIEDSIGNAL INC. ,  HE, Gang

IPC: G01J01/42

CPC classification number: G01N21/274 ,  G01J1/44

Abstract: A noise cancellation system which balances the photocurrents derived by a measurement signal and a reference signal of a sensor. The invention has application in any measurement device which detects a small signal in combination with high noise content and further utilizes a reference signal. The invention is useful in an optical measurement system by splitting an optical beam into measurement (28) and reference optical beams (26); passing the measurement through a sample cell (30) for measurement information; converting the measurement beam (28) and reference beam (26) into a measurement current representing information signals impressed on a current signal that is modulated by undesirable noise signals and a reference current representing said carrier current signal exclusive of said information signals and modulated by said noise signals respectively; generating a voltage source as a function of said reference current and a feedback control voltage resulting in the flow of a correction current modulated by said noise signals; and combining said measurement current and said correction current in a way which substantially cancels the undesirable noise signals from said measurement current and produces said feedback control voltage which comprises an output signal containing the information component of said measurement current. Other applications include acoustic, infrared, frequency or other types of measurement systems.

Abstract translation: 噪声消除系统，其平衡由测量信号导出的光电流和传感器的参考信号。 本发明可应用在任何测量装置中，该测量装置结合高噪声内容检测小信号并进一步利用参考信号。 本发明在通过将光束分成测量（28）和参考光束（26）的光学测量系统中是有用的; 将测量通过用于测量信息的样品池（30）; 将测量光束（28）和参考光束（26）转换成表示施加在由不期望的噪声信号调制的电流信号上的信号信号的测量电流，以及表示除所述信息信号之外的所述载波电流信号的参考电流，并由所述 噪声信号; 产生作为所述参考电流的函数的电压源和产生由所述噪声信号调制的校正电流的反馈控制电压; 以及以基本上抵消来自所述测量电流的不期望的噪声信号的方式组合所述测量电流和所述校正电流，并产生包括包含所述测量电流的信息分量的输出信号的所述反馈控制电压。 其他应用包括声学，红外，频率或其他类型的测量系统。

公开(公告)号：EP0900365A1

公开(公告)日：1999-03-10

申请号：EP97925546.0

申请日：1997-05-13

Applicant: AlliedSignal Inc.

Inventor： HE, Gang

IPC: G01J3 ,  G01J1 ,  G01N21 ,  G01R19

CPC classification number: G01N21/274 ,  G01J1/44

Abstract: A noise cancellation system which balances the photocurrents derived by a measurement signal and a reference signal of a sensor. The invention has application in any measurement device which detects a small signal in combination with high noise content and further utilizes a reference signal. The invention is useful in an optical measurement system by splitting an optical beam into measurement (28) and reference optical beams (26); passing the measurement through a sample cell (30) for measurement information; converting the measurement beam (28) and reference beam (26) into a measurement current representing information signals impressed on a current signal that is modulated by undesirable noise signals and a reference current representing said carrier current signal exclusive of said information signals and modulated by said noise signals respectively; generating a voltage source as a function of said reference current and a feedback control voltage resulting in the flow of a correction current modulated by said noise signals; and combining said measurement current and said correction current in a way which substantially cancels the undesirable noise signals from said measurement current and produces said feedback control voltage which comprises an output signal containing the information component of said measurement current. Other applications include acoustic, infrared, frequency or other types of measurement systems.

公开(公告)号：EP1062497A1

公开(公告)日：2000-12-27

申请号：EP99912338.3

申请日：1999-03-09

Applicant: AlliedSignal Inc.

Inventor： HE, Gang

IPC: G01N21/27

CPC classification number: G01N21/274

Abstract: An on-line self-calibrating system where prior calibration information is updated by combining prior stored calibration information with current sensor reading information to simulate the introduction of a known calibrating sample and to generate new calibration information. A preferred embodiment of the present invention is in a laser spectral absorption system for determining the concentration of a particular gas in a gaseous sample by sensing a characteristic narrow spectral pulse in the absorption characteristics of the sample, the area or spectral integration of the pulse being proportional to the concentration of the particular gas. The disclosed technique effects on-line recalibration of the system based on current operating parameters of the system to compensate for time or usage induced degradation in system accuracy without introducing a sample of a known concentration of the gas into the system.