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Author

Larry G. Stolarczyk

Bio: Larry G. Stolarczyk is an academic researcher. The author has contributed to research in topics: Antenna (radio) & Transmitter. The author has an hindex of 21, co-authored 52 publications receiving 1598 citations.
Topics: Antenna (radio), Transmitter, Signal, Coal, Radar


Papers
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Patent
02 Apr 2001
TL;DR: In this article, the authors present an approach for detecting anomalies in microwave penetrable material that may be used for locating plastic mines or pipes underneath the ground, where a transmitter is positioned at a plurality of different positions above the ground.
Abstract: Apparatus and methods are disclosed for detecting anomalies in microwave penetrable material that may be used for locating plastic mines or pipes underneath the ground. A transmitter is positioned at a plurality of different positions above the ground. A microwave signal is transmitted that is stepped over a plurality of frequencies. At each position, a plurality of reflections are received corresponding to each of the plurality of frequencies that were transmitted. A complex target vector may be produced at each position that contains complex values corresponding to magnitude, phase, and time delay for each of the plurality of reflections received at that location. A complex reference data vector may be produced, either based on predetermined values or based on data from the received plurality of reflections. A comparison is made between the complex target vector and the complex reference data vector to produce a channel vector. In one embodiment, an operator may be applied to the channel vector such as a complex filter matrix or to add a complex conjugate. A response signal is produced and anomalies are detected by variations in the response signal with respect to the plurality of positions.

305 citations

Patent
20 Nov 2008
TL;DR: An underground radio communications and personnel tracking system uses a portable communications device worn by a miner when underground in a mine as mentioned in this paper, which provides voice and text communication on ultra-low frequency (ULF) to ultra-high frequency (UHF) carrier frequencies and modulation adapted by programming of a software defined radio to making selective and agile radio contacts via through-the-earth, conductor/lifeline, coal seam, tunnel, and ionosphere/earth surface waveguides for transmission of electromagnetic waves.
Abstract: An underground radio communications and personnel tracking system uses a portable communications device worn by a miner when underground in a mine. A cap-lamp transceiver provides voice and text communication on ultra-low frequency (ULF) to ultra-high frequency (UHF) carrier frequencies and modulation adapted by programming of a software defined radio to making selective and agile radio contacts via through-the-earth, conductor/lifeline, coal seam, tunnel, and ionosphere/earth-surface waveguides for transmission of electromagnetic waves. These waveguides comprise layered earth coal and mineral deposits, and manmade mining complex infrastructures which serendipitously form efficient waveguides. Ultra-Low Frequency F1/F1 repeaters are placed underground in the mine, and providing for extended range of communication of the cap-lamp transceiver with radios and tracking devices above ground of the mine.

201 citations

Patent
16 Aug 1990
TL;DR: In this paper, the authors proposed a method for remotely monitoring conditions such as carbon monoxide or methane gas concentration, longwall roof support pressure, machine parameters or uncut coal, trona or potash layer thickness in a natural resource mining system such as a longwall or continuous mine system.
Abstract: A method for remotely monitoring conditions such as carbon monoxide or methane gas concentration, longwall roof support pressure, machine parameters or uncut coal, trona or potash layer thickness in a natural resource mining system such as a longwall or continuous mine system. The method utilizes a plurality of sensors connected to low magnetic moment transmitters, e.g. 0.1 ATM 2 , or high magnetic moment transmitters, e.g. 2.5 ATM 2 , that transmit collected data during multiple short burst transmission periods. Prior to transmission, the data is converted to a digital word format. An algorithm in the transmitter microcomputer ensures that random time intervals exist between data transmission bursts thus preventing a data transmission clash at the central receiver. A microcomputer algorithm in the central receiver protects against data contention caused by simultaneous transmission from several sensors. The data is transmitted to the central receiver either through a natural waveguide pathway or through a utility conductor that is magnetically coupled to the transmitter and central receiver by properly oriented electrically short magnetic dipole antennas. The method can be used, for example, to automatically control the positioning of a plurality of longwall roof supports or to transmit data from a longwall drillhead, along the drill rod, to the central receiver. Data can be communicated between a remote location and a surface area by utilizing a system of repeaters inductively coupled to a utility conductor. Use of the repeater system permits operation of mining machines from a surface computer.

142 citations

Patent
25 May 1988
TL;DR: In this article, a method for using an underground mine communication system to effect minewide communication and an intrinsically safe current limiter circuit for insuring that electrical equipment in the system will not cause incendiary conditions.
Abstract: A method for using an underground mine communication system to effect minewide communication and an intrinsically safe current limiter circuit for insuring that electrical equipment in the system will not cause incendiary conditions. The underground mine communication system comprises a plurality of repeaters (28) and medium frequency radios, including mobile (24), portable and personal-carried radios (26), coupled to electrical conductors (32) and natural waveguides existing in the earth by tuned loop antennas. Messages transmitted by the radios are carried to the repeaters by the conductors or coal seam waves. The repeaters amplify, replicate and retransmit the message at two different frequencies for transmission of the message to a surface base station and to other radios in the system. A paging system, which has a separate set of repeaters (29), is also coupled to the network of electrical conductors and natural waveguides by tuned loop antennas. The paging system alerts miners to contact the surface base station. Radios, pagers and repeaters in the system are equipped with the intrinsically safe current limiter circuit to preclude the development of incendiary conditions. The current limiter circuit comprises a series arrangement of a current trip circuit, a redundant current trip circuit and a current limiting field effect transistor controlled by a feedback control amplifier.

71 citations

Patent
29 Nov 1993
TL;DR: In this paper, a roadway sensor for surface installation in a hole such that a thin ceramic contact sensor may be used to measure and cross-compare fundamental physical antenna parameters of the space immediately above a roadway or bridge surface.
Abstract: An embodiment of the present invention is a roadway sensor for surface installation in a hole such that a thin ceramic contact sensor may be used to measure and cross-compare fundamental physical antenna parameters of the space immediately above a roadway or bridge surface. Measurements are combined by a microprocessor to discriminate between dry pavement, water (rain), snow and ice above the sensor head. Ambient surface temperature, water depth and ice/slush conditions are determined to estimate any hydroplaning hazard and ice/antifreeze/water mixtures. The sensor comprises an antenna that exhibits a resonant frequency and an input admittance including a real term; a Maxwell bridge coupled to the antenna for detecting the resonant frequency, input admittance and real term; and a frequency sweeping oscillator for driving the antenna at a plurality of frequencies proximate in frequency to the resonant frequency. A phase sensitive detector determines an attenuation rate and phase and thereby is able to extract a conductivity (σ) and a dielectric (e) measurement. The microprocessor relates the conductivity and dielectric measurements to yield, for example, a pair of estimates for ice and water content and layer thickness.

61 citations


Cited by
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Patent
13 Nov 2000
TL;DR: In this article, the authors present a system for monitoring a variety of environmental and/or other conditions within a defined remotely located region by using a plurality of wireless transmitters (614), each integrated into a sensor (612) adapted to monitor a particular data input.
Abstract: The present invention is generally directed to a system for monitoring a variety of environmental and/or other conditions within a defined remotely located region. In one aspect, a system is configured to monitor utility meters (613) in a defined area. The system is implemented by using a plurality of wireless transmitters (614), each integrated into a sensor (612) adapted to monitor a particular data input. The system also includes a plurality of transceivers (221) that are dispersed throughout the region at defined locations. The system uses a local gateway (210) to translate and transfer information from the transmitters to a dedicated computer (260) on a network (230). The dedicated computer collects, compiles and stores the data for retrieval upon client demand across the network. The computer further includes means for evaluating the received information and identifying an appropriate control signal to be applied at a designated actuator.

1,542 citations

Patent
01 Oct 1992
TL;DR: In this article, an apparatus and a method for routing data in a radio data communication system having one or more host computers, one/more intermediate base stations, and one/or more RF terminals is presented.
Abstract: An apparatus and a method for routing data in a radio data communication system having one or more host computers, one or more intermediate base stations, and one or more RF terminals organizes the intermediate base stations into an optimal spanning-tree network to control the routing of data to and from the RF terminals and the host computer efficiently and dynamically. Communication between the host computer and the RF terminals is achieved by using the network of intermediate base stations to transmit the data.

705 citations

Patent
15 Nov 2001
TL;DR: In this paper, a method for discharging fastening elements and a method of preventing a device from discharging a fastening device into human flesh was described. But the method was not discussed.
Abstract: A device for discharging fastening elements, and a method of preventing a device from discharging fastening devices into human flesh, are disclosed. The device includes a coil proximate a location of discharge, a capacitive element coupled in parallel with the conductive coil to form a resonant tank circuit, an oscillator that drives the tank circuit, a frequency detector, an amplitude control circuit and a processor. The detector detects a frequency of oscillation of the tank circuit as affected by a material proximate the coil. In response to an electrical signal from the oscillator, the control circuit generates a control signal that is provided back to the oscillator. Based upon the frequency and an additional signal functionally related to the control signal, the processor provides an output signal that prevents the device from discharging when the material proximate the coil is human flesh.

637 citations

Patent
09 Aug 2001
TL;DR: In this article, a wireless communication network for monitoring and controlling a plurality of remote devices is provided. But the protocol is not defined, and each of the wireless transceivers may be configured to receive a sensor data signal from one of the remote devices and transmit an orginal data message using a predefined wireless communication protocol.
Abstract: Wireless communication networks for monitoring and controlling a plurality of remote devices are provided. Briefly, one embodiment of a wireless communication network may comprise a plurality of wireless transceivers having unique identifiers. Each of the plurality of wireless transceivers may be configured to receive a sensor data signal from one of the plurality of remote devices and transmit an orginal data message using a predefined wireless communication protocol. The original data message may comprise the corresponding unique identifier and sensor data signal. Each of the plurality of wireless transceivers may be configured to receive the original data message transmitted by one of the other wireless transceivers and transmit a repeated data message using the predefined communication protocol. The repeated data message may include the sensor data signal and the corresponding unique identifier. Furthermore, at least one of the plurality of wireless transceivers may be further configured to provide the original data messages and the repeated data messages to a site controller connected to a wide area network. The site controller may be configured to manage communications between the wireless communication network and a host computer connected to the wide area network.

498 citations

Patent
29 Jul 2003
TL;DR: In this article, the authors proposed an improved apparatus for a radio communication system having a multiplicity of mobile transceiver units selectively in communication with a plurality of base transceivers which, in turn, communicate with one or more host computers for storage and manipulation of data collected by bar code scanners.
Abstract: Improved apparatus for a radio communication system having a multiplicity of mobile transceiver units selectively in communication with a plurality of base transceiver units which, in turn, communicate with one or more host computers for storage and manipulation of data collected by bar code scanners or other collection means associated with the mobile transceiver units. A network controller and an adapter which has a simulcast and sequential mode provide selective interface between host computers and base transceivers. A scheme for routing data through the communication system is also disclosed wherein the intermediate base stations are organized into an optimal spanning-tree network to control the routing of data to and from the RF terminals and the host computer efficiently and dynamically. Additionally, redundant network and communication protocol is disclosed wherein the network utilizes a polling communication protocol which, under heavy loaded conditions, requires that a roaming terminal wishing to initiate communication must first determine that the channel is truly clear by listing for an entire interpoll gap time. In a further embodiment, a criterion used by the roaming terminals for attaching to a given base station reduces conflicts in the overlapping RF regions of adjacent base stations.

445 citations