1987 results about "Probe signal" patented technology

The invention relates to a medical probe signal generator. More particularly, it relates to a medical probe signal generator architecture. The present invention further relates to a medical probe signal generator having an automatic probe type detector, a user interface and operational parameter settings automatically configured according to a type of medical probe connected to the generator.

An adaptive communication system utilises opportunistic peak-mode transmissions to transmit data between originating and destination stations, via one or more intermediate stations. Each station monitors the activity of other stations in the network, storing connectivity information for use in subsequent transmissions. Each station also sends out probe signals from time to time, to establish which other stations are in range. Messages are then sent across the network from station to station, with confirmation data being transmitted back to the originating station, until the destination station is reached. Old messages, which would otherwise clog the network, are timed out and deleted. A communication network and transceiver apparatus for use in the network are also disclosed.

A wafer-level testing arrangement for opto-electronic devices formed in a silicon-on-insulator (SOI) wafer structure utilizes a single opto-electronic testing element to perform both optical and electrical testing. Beam steering optics may be formed on the testing element and used to facilitate the coupling between optical probe signals and optical coupling elements (e.g., prism couplers, gratings) formed on the top surface of the SOI structure. The optical test signals are thereafter directed into optical waveguides formed in the top layer of the SOI structure. The opto-electronic testing element also comprises a plurality of electrical test pins that are positioned to contact a plurality of bondpad test sites on the opto-electronic device and perform electrical testing operations. The optical test signal results may be converted into electrical representations within the SOI structure and thus returned to the testing element as electrical signals.

The search/detection apparatus modulates a carrier signal by a modulation signal, generates a probe signal for detecting the location of a target, and receives the probe signal reflected by the target as an echo signal. Then, the search/detection apparatus detects the existence of an interference signal other than the echo signal from the received signal and modifies the parameter of the modulation signal and/or carrier signal.

The invention discloses a D2D (Dimension To Dimension) pair/D2D cluster communication building method which comprises the following steps that: 1) initiator user equipment actively sends a cluster building request signaling code to a base station via a honeycomb link, wherein the content of the cluster building request signaling code comprises a communication mode, user equipment capability and a business label; 2) after the base station receives the cluster building request signaling code, the relevant information of the initiator user equipment is measured and analyzed so as to be combined with a system information selecting and scheduling mechanism to broadcast the cluster building request signaling code; 3) after the initiator user equipment and the adjacent user equipment receive the cluster building request signaling code, analysis is carried out by aiming at a cluster building strategy message; 4) the initiator user equipment sends a channel probing signal; the adjacent user equipment measures the D2D link quality; and the adjacent user equipment, which satisfies the requirement and serves as the candidate cluster use equipment, sends the cluster building confirmation message. According to the D2D pair/D2D cluster communication building method, the traditional cluster communication building flow simplified, resources are saved, and time delay is lowered.

A wireless terminal using OFDM signaling supporting both terrestrial and satellite base station connectivity operates using conventional access probe signaling in a first mode of operation to establish a timing synchronized wireless link with a terrestrial base station. In a second mode of operation, used to establish a timing synchronized wireless link with a satellite base station, a slightly modified access protocol is employed. The round trip signaling time and timing ambiguity between a wireless terminal and a satellite base station is substantially greater than with a terrestrial base station. The modified access protocol uses coding of access probe signals to uniquely identify a superslot index within a beaconslot. The modified protocol uses multiple access probes with different timing offsets to further resolve timing ambiguity and allows the satellite base station access monitoring interval to remain small in duration. Terrestrial base station location/connection information is used to estimate initial timing.

A TDR for locating impairments in an HFC network is claimed. The network carries burst signals in an upstream band during burst intervals. The TDR comprises a transmitter, receiver, level detector, controller, accumulator, and probe detector. The transmitter transmits probe signals to the impairment, causing a reflection of the probe signals. Each probe signal is in the upstream band and has a bandwidth extending the width of the upstream band. The receiver receives the reflected probe signals during receiving intervals, and receives the burst signals during receiving intervals that overlap burst intervals. The level detector measures a level of the signals received during each receiving interval. The controller determines which of the receiving intervals are free of burst signals, based on the level measurement. The accumulator accumulates reflected probe signals received during intervals free of burst signals. The probe detector detects the impairment from the accumulated probe signals and estimates a time delay for the impairment. A distance to the impairment is estimated from the time delay.

Devices for sensing at an underground drilling device in communication with an above-ground locator involve transmitting a radar probe signal from the underground drilling device. A radar return signal is received at the underground drilling device. The radar return signal is processed at the underground drilling device to produce sensor data. The sensor data is transmitted in a form suitable for reception by the above-ground locator.

A target 22 is explored by transmitting an exploration signal 40 at a certain angle while scanning an antenna 23. In the go and return exploration the angle for transmitting the exploration signal is shifted. It is possible to detect the direction of the target 22 with the same accuracy as that in exploration with a more minute angle difference, by combining the exploration results with the angle shifted in a plurality of scans. Relative travel of the target 22 that accompany a plurality of scans is considered as a Doppler shift and a combination of data is used considering the frequency shift. Data that cannot be combined is treated as an unwanted reflective object and the position where unwanted reflecting objects assemble is obtained and the position is determined as a shoulder. The height of a stationary target is determined from the variation in the reflected signal level in an approach to the stationary target.

A process and device for detecting electrically conductive particles in a liquid flowing in a pipe section, the liquid being exposed to periodic alternating electromagnetic fields by a transmitter coil which induces eddy currents in the particles, a probe made as a coil arrangement and which has an effective width producing a periodic electrical signal based on the eddy currents. The signal ha a carrier oscillation with an amplitude and/or phase which is modulated by particles passing across the effective width of the coil arrangement, the probe signal being filtered by a frequency-selective first filter unit, the filtered signal being sampled by a triggerable A/D converter stage to obtain a demodulated digital measurement signal, the digital measurement signal being filtered by a digital, frequency-selective adjustable second filter unit to obtain a useful signal, and the useful signal being evaluated to detect passage of electrically conductive particles in the pipe section.

A method and apparatus is provided for obtaining status information from a given location along an optical transmission path. The method begins by generating a cw probe signal having a prescribed frequency that is swept over a prescribed frequency range. The cw probe signal is transmitted over the optical path and a returned COTDR signal in which status information concerning the optical path is embodied is received over the optical path. A receiving frequency within the prescribed frequency range of the returned COTDR signal is detected to obtain the status information. The detecting step includes the step of sweeping the receiving frequency at a rate equal to that of the prescribed frequency. A period associated with the receiving frequency is temporally offset from a period associated with the prescribed frequency.

Systems and methods are disclosed for distributed temperature and strain sensing along a length of an infrastructure. Two optical sources, such as, external cavity lasers with a narrow linewidth, are used for launching a probe signal into a sensing fiber coupled to the infrastructure, and for producing a local oscillation signal, respectively. The optical sources are coherently locked with a predefined frequency offset with respect to each other, the predefined frequency offset being in the order of the Brillouin frequency shift. The optical sources are included in an optical phase lock loop (OPLL) system. A balanced heterodyne receiver for narrow band detection at radio frequency (RF) bandwidth receives an optical signal generated by coherent mixing of a backscattered probe signal with the Brillouin frequency shift and the local oscillation signal, and produces an output indicative of one or both of a measured temperature and a measured strain.

The invention discloses a distribution-type optical-fiber vibration sensor which is based on polarization-state differential detection and can localize multiple points of vibration sources, and the sensor is characterized in that on the basis of the traditional optical time domain reflectometer, a polarization beam splitter is used for detecting a polarization state of backward scattered light in sensing optical fibers, two beams of orthogonal polarization light which is outputted by the polarization beam splitter are respectively photoelectrically converted by two photoelectric detectors, then differential operation and amplification processing is conducted for two detected signals, the signals are sampled by an analog/digital (A/D) converter, and the sample is sent into an embedded computer to be data analyzed and computed so as to realize the precise localization of the vibration sources which are distributed along the axial direction of the optical fibers. Due to adopting the multi-point localizable distribution-type optical-fiber vibration sensor, the simultaneous localization of multi-point weak vibration sources which are distributed along the axial direction of the optical fibers can be realized. The multi-point localizable distribution-type optical-fiber vibration sensor is simple and reliable, easy to implement and maintain and suitable for the detection and precise localization of the weak vibration signal sensed by the long-distance laid optical fibers.

In a method and a corresponding apparatus for performing chaotic optical time domain reflectometer, the chaotic laser signal, generated by the chaotic laser transmitter, is split into probe signal I and reference signal II by a fiber coupler. Through an optical circulator, the probe signal I is launched into the test fiber and the echo light is converted into electrical signal by a photodetector and digitalized by an A/D converter. The reference signal II is converted into electrical signal by a photodetector and digitalized by another A/D converter. Two digital signals received from two A/D converters are correlated in a signal processing device to locate the exact position of faults in fibers. The result output is then displayed on a display device. This invention was developed to overcome the tradeoff between resolution and dynamic range of the pulse-based OTDR. This method can improve the dynamic range and spatial resolution significantly; enhance the anti-jamming capability and noise tolerance. Also it has merits of simple structure and lower cost.