摘要:
A narrowband impulse radio system includes a transmitter, transmitting a plurality of harmonic signals, and a receiver, receiving the signals, wherein the signals cooperate in a constructive alignment to yield a narrowband impulse signal of amplitude approximately equal to the sum of the amplitudes of the plurality of harmonic signals. The transmitter or the receiver may employ a plurality of phase shifters to effect the cooperation in the transmitted or received signals, respectively. The harmonic signals cooperate to yield a quasi-DC signal whose pulse rate equals the fundamental harmonic frequency. In a preferred embodiment, the narrowband impulse transmitter further includes a plurality of transmit modules each transmitting one of the plurality of harmonics. The plurality of transmit modules may employ magnetic antennas characterized by a magnetic axis aligned at an angle of approximately 55 degrees relative to a common axis, or in other embodiments, may employ mechanically rotating permanent magnets.
摘要:
A directive electrically small antenna (DESA) process and method employs multipole synthesis to implement directive electrically small multipole antennas with ultra-wideband (UWB) stable antenna patterns. Although lossy, embodiments have adequate efficiency to work as receive antennas in the high ambient noise environment of the HF band and below. Employing a process dubbed “antenna regeneration,” energy may be circulated within an antenna by means other than resonance. This enables multiple decade UWB response without the efficiency penalties inherent to traditional resistively-loaded antenna systems. Regenerative antennas can simultaneously achieve the performance of high Q resonant antennas and the bandwidth of resistively loaded antennas.
摘要:
A multiple phase state near-field electromagnetic location and communication system includes a multiple phase state near-field transmitter, and a near-field locator receiver. The near-field transmitter is capable of operation in at least two states and each of these at least two states generates a state characteristic difference detected at the near-field locator receiver. The state characteristic difference may be employed for location determination, communication or both. The present invention is particularly well-suited for use in conjunction with a near-field electromagnetic ranging system. In further embodiments, a multiple phase state near-field electromagnetic location and communication process includes the steps of determining a transmission state for a near-field quadrature transmitter, transmitting a near-field transmission corresponding to said transmission state, receiving a near-field transmission corresponding to said transmission state, and determining a difference between at least two properties of said near-field transmission where the difference is characteristic of and corresponding to the transmission state.
摘要:
An inventory control system and method uses a locating device associated with a mover and identifies an ID tagged asset using an ID reader also associated with the mover. Thus, a single relatively high-cost locating device may be temporarily associated with the asset, enabling precise location of a multitude of assets as a mover traverses an inventory area. The asset location and identification may be associated in a database. The asset location may be refined by using additional measurement devices, for example a forklift height sensor, to determine extension from a locating device. A further embodiment utilizes RFID or barcode technology for the ID tag. The locating device may utilize near-field location technology, signals-of-opportunity, or other RTLS technologies.
摘要:
A system and method for determining a position of a locus comprising a locator device for disposition at the locus; the locator device configured for receiving an electromagnetic signal from a beacon device, the locator device receiving at a distance from the beacon device within near field range of the electromagnetic signal; the locator device configured for distinguishing at least two characteristics of the electromagnetic signal sensed at the locus; the system employing the at least two characteristics to effect the determining of the position of the locus.
摘要:
A space efficient magnetic antenna is disclosed for use in tracking, positioning and other applications. In a preferred embodiment, a space efficient magnetic antenna system comprises a first magnetic antenna with a first null axis aligned within a predetermined plane and a second magnetic antenna having a second null axis aligned substantially orthogonal to a first null axis. A second magnetic antenna system lies in a minimal coupling orientation with respect to a first magnetic antenna system. Additionally, a first magnetic antenna may further comprise a plurality of interconnected magnetic antenna elements. A space efficient magnetic antenna system may include an RF module. In further embodiments, the antenna system may enclose a substantial majority of the device including the RF module; the RF module may be enclosed substantially or wholly within one or more antennas of the antenna system.
摘要:
A multiple phase state near-field electromagnetic location and communication system includes a multiple phase state near-field transmitter, and a near-field locator receiver. The near-field transmitter is capable of operation in at least two states and each of these at least two states generates a state characteristic difference detected at the near-field locator receiver. The state characteristic difference may be employed for location determination, communication or both. The present invention is particularly well-suited for use in conjunction with a near-field electromagnetic ranging system. In further embodiments, a multiple phase state near-field electromagnetic location and communication process includes the steps of determining a transmission state for a near-field quadrature transmitter, transmitting a near-field transmission corresponding to said transmission state, receiving a near-field transmission corresponding to said transmission state, and determining a difference between at least two properties of said near-field transmission where the difference is characteristic of and corresponding to the transmission state.
摘要:
An apparatus and method for low frequency asset tracking includes a low frequency transmitter tag associated with a cargo container or other high value commodity, a plurality of receivers that detect low frequency signals, and a microprocessor that uses algorithms and/or data pertaining to the propagation characteristics of the signal to locate the position of the container or high value commodity. The tag may include sensors to monitor container properties or conditions, such as temperature, motion, intrusion, RF fields, or other properties of interest. Sensor data may be modulated on the low frequency transmitter signal.
摘要:
A space efficient magnetic antenna is disclosed for use in tracking, positioning and other applications. In a preferred embodiment, a space efficient magnetic antenna system comprises a first magnetic antenna with a first null axis aligned within a predetermined plane and a second magnetic antenna having a second null axis aligned substantially orthogonal to a first null axis. A second magnetic antenna system lies in a minimal coupling orientation with respect to a first magnetic antenna system. Additionally, a first magnetic antenna may further comprise a plurality of interconnected magnetic antenna elements. A space efficient magnetic antenna system may include an RF module. In further embodiments, the antenna system may enclose a substantial majority of the device including the RF module; the RF module may be enclosed substantially or wholly within one or more antennas of the antenna system.
摘要:
A system and method for identification and location of an asset by tracking the mover of the asset using a locating device associated with the mover and identifying the asset using an identification reader associated with the mover and a passive identification tag associated with the asset. A single mover may move many assets. An asset is identified; the mover then moves the asset to a destination location, whereupon the mover and asset position are determined. The asset location may then be recorded in memory. The measurement of the destination location may be extended from the location measured by the active location device by using additional measurement devices, for example a forklift height sensor. A further embodiment utilizes RFID or barcode technology for the passive tag and may utilize near field positioning technology for the active location device.