Abstract: FIG 1 of the drawings has been amended to include arrows 12a and 12b. The word “laser”, the arrow symbol underneath the word “laser” and the partial sinusoidal symbol adjacent the word “laser”have all been deleted. In addition, the word “photodetector” deleted and a dashed line circumscribing the photodetector componants has been added along with reference numeral 25. Reference numeral 24 has been added to denote the photodiode. Finally, the photodiode symbol associated with oscillator apparatus 12 has been changed to simply indicate a “Gain Cavity” box. The attached “Replacement Sheet(s)”of drawings include changes to FIG. 1. The attached “Replacement Sheet(s),”which include(s) FIG(S.) 1 and 2, replace the original sheet(s) including FIG(S.) 1 and 2.

Abstract: A method and system for performing swept-wavelength measurements within an optical system provides improved operation in resonator-enhanced optical measurement and data storage and retrieval systems. The system includes an illumination subsystem having a swept-wavelength mode, a detection subsystem, an interferometer or an optical resonator interposed in an optical path between the illumination subsystem and the detection subsystem and a time domain analysis subsystem. Multiple resonance points of the optical resonator are detected by the time-domain subsystem when the illumination subsystem is in the swept-wavelength mode in order to determine resonator or interferometer characteristic changes. The resulting information can be used directly as a measurement output, or cavity length information may also be used to adjust the operating wavelength of a constant wavelength mode of the illumination subsystem.

Abstract: An apparatus and method of dynamically optimizing an acquisition range of a radar system, including modulating a CW radar signal with a PN code that has an adjustable code frequency of modulation and an adjustable chip length. The method includes transmitting the modulated radar signal and receiving a return radar signal, based on the transmitted radar signal. The method continuously measures a SNR of the received return radar signal, and adaptively tunes the adjustable code frequency of modulation, and adaptively tunes the adjustable chip length, based on the continuously measured SNR. In this manner, the acquisition range of the radar system is optimized.

Abstract: A method and apparatus of measuring a distance to a reflection object is disclosed. A sensitivity time control (STC) process is applied to a received signal from the reflection object to provide an STC-processed signal. The radar apparatus includes a controller. The controller obtains a quantity corresponding to the distance from a transmission time of the transmission signal and a detection time of the STC-processed signal. The quantity is corrected by using a first correction value associated with the intensity of the STC-processed reflection signal to provide a corrected quantity. The corrected quantity is further corrected by using a second correction value associated with the corrected quantity and the intensity of the STC-processed reflection signal to correct the error regardless of the intensity of the STC-processed reflection signal.

Abstract: A code generating device operates for generating a pseudo random noise code having a sequence of a predetermined number of chips each being in one of first and second logic states different from one another. A code monitoring device operates for detecting at least a preset number of successive chips in the first logic state in the pseudo random noise, and for changing at least one among the detected preset number of successive chips to the second logic state to convert the pseudo random noise code into a transmission signal. A driving device operates for activating and deactivating an electromagnetic wave generating device in response to the transmission signal. A receiving device operates for receiving an echo wave caused by reflection of an electromagnetic wave generated by the electromagnetic wave generating device at an object. A distance to the object is detected on the basis of the received echo wave.

Abstract: A method and system are provided for measuring water current direction and magnitude. A plurality of beams of radiation are transmitted radially outward from a location above a body of water. Each beam is incident on the water's surface at an angle with respect thereto. Each beam experiences a Doppler shift as a result of being incident on the water's surface such that a plurality of Doppler shifts are generated. Each Doppler shift is measured with the largest one thereof being indicative of water current direction and magnitude.

Abstract: A forward electromagnetic wave is generated in accordance with a succession of pseudo random noise code signals. An echo electromagnetic wave caused by reflection of the forward electromagnetic wave at an object is converted into a received signal. Direct-current and low-frequency components are removed from the received signal to generate a filtering-resultant signal. The filtering-resultant signal is compared with a preset decision reference voltage to generate a binary signal. The binary signal is sampled into received data. Calculation is made as to a correlation between the received data and the pseudo random noise code signal. The distance to the object is computed on the basis of the calculated correlation. The pseudo random noise code signal is repetitively generated to produce a succession of the pseudo random noise code signals during a surplus time covering a stabilization time taken by the received signal to stabilize in direct-current voltage level.

Abstract: A method of determining a range of an object includes emitting light toward a target and sensing light reflected by the target. Signals corresponding to the sensed light are integrated during multiple integration periods. Each integration period is different from other integration periods. A range of the target can be calculated based on the integrated signals. A range finder for performing the foregoing technique also is disclosed.

Abstract: A method and apparatus for generating three-dimensional range images of spatial objects, wherein a short-time illumination of the object is performed, for instance using laser diodes. An image sensor is used that has a high light sensitivity, pixel resolution and can be read out randomly, this sensor also having an integration time that can be adjusted for each pixel. By evaluating the backscattered laser pulses in two integration windows with different integration times and by averaging over several laser pulses, three-dimensional range images can be picked up with a high reliability in, for example, 5 ms at the most.

Abstract: An electronic distance meter includes a sighting telescope having an objective lens for sighting an object; a reflection member positioned behind the objective lens; an optical distance meter which includes a light-transmitting optical system for transmitting a measuring light via the reflection member and the objective lens, and a light-receiving optical system for receiving light which is reflected by the object, subsequently passed through the objective lens and not interrupted by the reflection member; a beam-diameter varying device, provided in association with the light-transmitting optical system, for varying a beam diameter of the measuring light; and a controller which varies the beam diameter via the beam-diameter varying device in accordance with a distance from the object to the electronic distance meter.

Abstract: A process for determining the distance (D) between a distance sensor and an object. A transmitter sends wave pulses with a predetermined first frequency fb 1 and the wave pulses reflected by the object are received by a receiver and are directed in the form of an analog electrical incoming signal to an A-D converter. The latter scans the incoming signal with a second frequency f2 with f2>f1 and converts it into a digital signal Z(t) which is evaluated for determining a distance value (D) in the following manner: a) Evaluation of the digital signal Z(t) for determining a first wave pulse propagation time (T1); b) k-fold repetition of the step a) for determining the total k wave pulse propagation times (T1, T2, . . . , Tk); c) Calculation of a mean wave pulse propagation time (T=(T1+T2+ . . . +Tk)/k); and d) Calculation of the distance value (D) in accordance with D−v=T/2.

Abstract: Dithered-edge sampling (DES) enables ultra-wideband measurement of terahertz pulses (far infrared electromagnetic pulses) using photoconductive antennas. The terahertz pulse is sampled by first passing it through a triggered photoconductive attenuator whose fast attenuation edge (limited only by the duration of the optical gating pulse) is dithered in time. A slow photoconductive receiver then measures the component of the terahertz electric field that is modulated at the dither frequency. The current through the photoconductive element constituting the receiver passes through a locking amplifier which may be operated at dither frequency. When used alone, the receiver blurs the measured terahertz pulse width. However, the increased time resolution provided by DES enables measurement of source-limited terahertz pulse widths. In addition, DES may be used to make direct measurements of a photoconductive receiver's temporal response.

Abstract: A highly precise range measurement instrument is made possible through the use of a novel and efficient precision timing circuit which makes use of the instrument's internal central processing unit crystal oscillator. A multi-point calibration function includes the determination of a “zero” value and a “cal” value through the addition of a known calibrated pulse width thereby providing the origin and scale for determining distance with the constant linear discharge of capacitor.