Abstract:
An optical sensor generates blood pressure data by obtaining two dimensional images of the surface of the patient's body, such as in the vicinity of the radial artery in the wrist area. Blood flow in the patient causes light to be reflected off a flexible reflective surface applied against the patient with a hold down pressure, and the scattering of light is sensed with a two-dimensional array of photo-detectors. The output of the photo-detectors during systolic and diastolic events is calibrated against known blood pressure measurements taken with a conventional air-cuff sphygmomanometer. Linear calibration relationships between output signal and blood pressure are obtained during calibration for some set of the photo-detectors. When blood pressure data is obtained from the patient, the linear calibration relationship between output signals and blood pressure is applied to the output signals from the set of photo-detectors, resulting in blood pressure data. The method provides for compensation for changes in hold down pressure and translation or rotation of the optical sensor relative to the patient. A preferred optical sensor arrangement for use in performing the method is also described.
Abstract:
An optical sensor (12) generates blood pressure data by obtaining two dimensional images of the surface of the patient's body, such as in the vicinity of the radial artery in the wrist area. Blood flow in the patient causes light to be reflected off a flexible reflective surface (14) applied against the patient with a hold down pressure, and the scattering of light i s sensed with a two-dimensional array (17) of photo-detectors (18). The output of the photo-detectors during systolic and diastolic events is calibrated against known blood pressure measurements taken with a conventional air-cuff sphygmomanometer. Linear calibration relationships between output signal and blood pressure (FIG. 25) are obtained during calibration for some set of the photo-detectors. When blood pressure data is obtained from the patient, the linear calibration relationship between output signals and blood pressure is applied to the output signals from the set of photo-detectors, resulting in blood pressure data. The method provides for compensation for changes in hol d down pressure and translation or rotation of the optical sensor relative to the patient. A preferred optical sensor arrangement for use in performing th e method is also described.
Abstract:
A blood pressure sensor (12) includes a source of photo-radiation, such as a n array (30) of laser diodes (30A-I). The sensor also includes a two- dimensional, flexible reflective surface (14). The reflective surface is nominally positioned relative to the radiation source such that the radiatio n travels in a direction normal to the reflective surface. The reflective surface is placed adjacent to the location on the patient where the blood pressure data is to be acquired. Radiation from the source is reflected off of the reflective surface onto a two-dimensional array (17) of photo-detectors (18). Systolic and diastolic blood pressure fluctuations in the patient are translated into deflections of the patient's skin. These deflections cause corresponding deflections in the two dimensional reflective surface. The associated movement of said flexible reflective surface (14) due to blood pulsation causes scattering patterns from said reflective surface to be detected by the two dimensional array (17) of photo-detectors (18). The outp ut from the array of photo-detectors is calibrated to blood pressure in mmHg during a calibration procedure to obtain a set of calibration relationships for one or more of the individual detectors. The calibration relationships a re then used during acquisition of blood pressure data to arrive at blood pressure data.
Abstract:
A wireless, programmable system for medical monitoring includes a base unit (18) and a plurality of individual wireless, remotely programmable biosensor transceivers (20). The base unit (18) manages the transceivers (20) by issui ng registration, configuration, data acquisition, and transmission commands usi ng wireless techniques. Physiologic data from the wireless transceivers (20) ar e demultiplexed and supplied via a standard interface to a conventional monito r (914) for display. Initialization, configuration, registration, and manageme nt routines for the wireless transceivers and the base unit are also described.
Abstract:
A wireless, programmable system for bio-potential signal acquisition (e.g., electrocardiogram (ECG) data) includes a base unit and a plurality of individual wireless, remotely programmable transceivers that connect to patch electrodes. The base unit manages the transceivers by issuing registration, configuration, data acquisition, and transmission commands using wireless techniques. Bio-potential signals from the wireless transceivers are demultiplexed and supplied via a standard interface to a conventional monitor for display.
Abstract:
A wireless, programmable system for medical monitoring includes a base unit (18) and a plurality of individual wireless, remotely programmable biosensor transceivers (20). The base unit (18) manages the transceivers (20) by issuing registration, configuration, data acquisition, and transmission commands using wireless techniques. Physiologic data from the wireless transceivers (20) are demultiplexed and supplied via a standard interface to a conventional monitor (914) for display. Initialization, configuration, registration, and management routines for the wireless transceivers and the base unit are also described.
Abstract:
A measurement device (103) and method determines various metrics between a vehicle (101) and a ground surface (105) using a transmitter-antenna (109) for emitting energy including a portion directed down toward the ground surface. A receiving antenna (115) has a portion oriented facing toward the transmitter-antenna for receiving a portion of the emitting energy along a direct path (117), and a portion oriented facing downwardly toward the ground surface for receiving a portion of the emitting energy reflected from the ground surface along a reflected path (113). A decoder provides separate indications of forward (121) and sideward (123) velocity relative to motion of the vehicle along the ground surface. Furthermore, the decoder comprises means for determining vehicle height (125) dependent on a measured difference in path length, vehicle level (127), or front to rear tilt angle, dependent on polarization elliptical ratio changes, and road surface conditions (129) dependent on amplitude and phase changes that occur versus time.
Abstract:
An RF tag (10) includes an RF receiver (16) and an RF transmitter (18). A power source (12) provides power to the receiver and transmitter. The power source includes a plurality of energy converters (22, 24, 26, 28, 30 and 32). Each energy converter is responsive to a predetermined form of incident energy for converting its respective predetermined form of incident energy to electrical current. At least two of the energy converters are responsive to respective different predetermined forms of incident energy for providing electrical current. A storage capacitor (54) stores the electrical current provided by the energy converters and is coupled to the RF receiver and RF transmitter. A plurality of RF tags (10, 110, 140, 160) utilizing the power source 12 are also described.
Abstract:
RF tagging system (10) has a plurality of resonant circuits (13) on a tag (12). When the tag (12) enters a detection zone (14), the system determines the resonant frequencies of each of the resonant circuits (13) and produces a corresponding code. Preferably, resonant frequency detection is implemented by simultaneously radiating signals at each possible resonant frequency for the tag circuits (13). The system is useful for coding any articles such as baggage or production inventory. Preferably, the radiated signals are phase shifted during the detection process, and signals received by receiver antennas, besides transmitter signals, may be monitored to improve the reliability of detecting the resonant circuits (13). Also, a preferred step adjustment configuration for capacitive metalizations (106, 110) of the resonant circuits is described. For radiating signals into the detection zone (14), focused beam antennas (201) may be used such that each resonant circuit location on the tag can be separately monitored. Also, an apparatus (300) for producing customized resonant circuit tags in accordance with a specified input code is described.
Abstract:
An optical sensor (12) generates blood pressure data by obtaining two dimensional images of the surface of the patient's body, such as in the vicinity of the radial artery in the wrist area. Blood flow in the patient causes light to be reflected off a flexible reflective surface (14) applied against the patient with a hold down pressure, and the scattering of light is sensed with a two-dimensional array (17) of photo-detectors (18). The output of the photo-detectors during systolic and diastolic events is calibrated against known blood pressure measurements taken with a conventional air-cuff sphygmomanometer. Linear calibration relationships between output signal and blood pressure (FIG. 25) are obtained during calibration for some set of the photo-detectors. When blood pressure data is obtained from the patient, the linear calibration relationship between output signals and blood pressure is applied to the output signals from the set of photo-detectors, resulting in blood pressure data. The method provides for compensation for changes in hold down pressure and translation or rotation of the optical sensor relative to the patient. A preferred optical sensor arrangement for use in performing the method is also described.