Abstract: A coal bed anomaly detection and imaging system comprises a synchronous transmitter and receiver that are separated by a geologic structure with embedded and hidden anomalies. The transmitter sends out two signals from magnetic dipole antennas. Such signals are widely separated in frequency but synchronized internally in the transmitter to one another. The higher frequency is used to make phase shift and attenuation measurements at the receiver by synchronous detection. The lower frequency is used at the receiver to synchronize the receiver to the transmitter. The higher frequency signal is measurably affected by anomalies in the intervening geologic structure. The lower frequency signal is fixed low enough so it is not substantially affected by the intervening geologic structure. Geologic modeling tools are preferably downloaded by geoscientists to their personal computers.

Abstract: A radar-plow drillstring steering system comprises a steering plow and a measurements-while-drilling instrument for mounting just behind the drill bit and downhole motor of a drill rod. The instrument includes a radar system connected to upward-looking and downward-looking horn antennas and a dielectric-constant sensor. The steering plow includes four pressure pads radially distributed around the outside surface and their associated servo motors. A coordinated control of the pressure pads allows the steering plow to push the drillstring and drill bit up-down-left-right. The antennas and sensor are embedded in respective ones of the pressure pads and are used to electronically and non-invasively probe a coal seam to locate its upper and lower boundary layers. The dielectric-constant sensor provides corrective data for the up and down distance measurements. Such measurements and data are radio communicated to the surface for tomographic processing and user display.

Abstract: A coal bed anomaly detection and imaging system comprises a synchronous transmitter and receiver that are separated by a geologic structure with embedded and hidden anomalies. The transmitter sends out two signals from magnetic dipole antennas. Such signals are widely separated in frequency but synchronized internally in the transmitter to one another. The higher frequency is used to make phase shift and attenuation measurements at the receiver by synchronous detection. The lower frequency is used at the receiver to synchronize the receiver to the transmitter. The higher frequency signal is measurably affected by anomalies in the intervening geologic structure. The lower frequency signal is fixed low enough so it is not substantially affected by the intervening geologic structure. Geologic modeling tools are preferably downloaded by geoscientists to their personal computers.

Abstract: A radio power output amplifier comprises a balanced radio power output that differentially drives a dipole antenna or other balanced load. One half of the differential power output drives one side of the antenna from ground to the maximum positive rail, while the other half of the differential power output drives the opposite side of the antenna from the maximum positive rail to ground. The result is a voltage swing across the antenna that is twice that which would occur if a single ended output was driving an unbalanced load. Since the power output is the square of the voltage divided by the load impedance, the result is four times the power output.

Abstract: A coal bed anomaly detection and imaging system comprises a synchronous transmitter and receiver that are separated by a geologic structure with embedded and hidden anomalies. The transmitter sends out two signals from magnetic dipole antennas. Such signals are widely separated in frequency but synchronized internally in the transmitter to one another. The higher frequency is used to make phase shift and attenuation measurements at the receiver by synchronous detection. The lower frequency is used at the receiver to synchronize the receiver to the transmitter. The higher frequency signal is measurably affected by anomalies in the intervening geologic structure. The lower frequency signal is fixed low enough so it is not substantially affected by the intervening geologic structure. Geologic modeling tools are preferably downloaded by geoscientists to their personal computers. The total attenuation and phase shift measurements are plugged into a full-wave inversion code (FWIC) process.

Abstract: A radar-plow drillstring steering system comprises a steering plow and a measurements-while-drilling instrument for mounting just behind the drill bit and downhole motor of a drill rod. The instrument includes a radar system connected to upward-looking and downward-looking horn antennas and a dielectric-constant sensor. The steering plow includes four pressure pads radially distributed around the outside surface and their associated servo motors. A coordinated control of the pressure pads allows the steering plow to push the drillstring and drill bit up-down-left-right. The antennas and sensor are embedded in respective ones of the pressure pads and are used to electronically and non-invasively probe a coal seam to locate its upper and lower boundary layers. The dielectric-constant sensor provides corrective data for the up and down distance measurements. Such measurements and data are radio communicated to the surface for tomographic processing and user display.

Abstract: A drillstring radar comprises a measurements-while-drilling instrument for mounting just behind the drill bit and downhole motor of a drill rod. The instrument includes a radar system connected to upward-looking and downward-looking horn antennas. These are used to electronically probe the interface of a coal seam with its upper and lower boundary layers. A dielectric constant sensor is included to provide corrective data for the up and down distance measurements. Such measurements and data are radio communicated to the surface for tomographic processing and user display. The instrument also includes a navigation processor and drill bit steering controls. The radio communication uses the drillstring as a transmission line and F1/F2 repeaters can be placed along very long runs to maintain good instrument-to-surface communication.

Abstract: A coalbed methane borehole pipe liner perforation system comprises a plastic pipe punch that slips down inside a coalbed methane production borehole lined with a non-perforated plastic pipe. A ground-penetrating radar is used inside the plastic-pipe lined borehole to determine which sections of the pipe are in contact with groundwater. The punch is then operated along the length of the plastic-pipe lined borehole to perforate it for methane-gas collection wherever such groundwater is not present. A radar survey to determine groundwater contact can be made simultaneously in combination with the punching of liner pipe perforations, or earlier in a separate operation.

Abstract: Most mines and underground facilities employ standardized construction techniques and materials. Such also cannot avoid having some above ground openings to receive utilities, fresh air, supplies, etc. Those or other surface openings are also universally used to discharge ground water, wastes, and other materials. Typical underground facilities have abundant electrical wiring and power demands, both of which can be detected at the surface. Levees with leakage pathways also form electrical conductors. When properly illuminated with remotely generated electromagnetic (EM) radiation, many of these features will “glow” or reradiate the radio energy in an electronic signature unique to the underground facility. Synchronized EM-gradiometer transponders are situated nearby on the ground surface to collect and analyze the “glow”. Alternative transmitting devices further includes ways to generate the illumination, and computers for characterizing the return signatures.

Abstract: A coal bed anomaly detection and imaging system comprises a synchronous transmitter and receiver that are separated by a geologic structure with embedded and hidden anomalies. The receiver is housed in a shuttle body that can be pumped into a borehole by water or air pressure. The shuttle may itself employ hydraulic inching mechanism to move within the drillhole. Signal measurements are reported out over a fiberoptic pigtail. A separate radio signal path provides synchronization between the transmitter and receiver. The receiver shuttle is tethered by this fiberoptic pigtail, and it can be withdrawn from the borehole by the tether.

Abstract: A coal bed anomaly detection and imaging system comprises a synchronous transmitter and receiver that are separated by a geologic structure with embedded and hidden anomalies. The transmitter sends out two signals from magnetic dipole antennas. Such signals are widely separated in frequency but synchronized internally in the transmitter to one another. The higher frequency is used to make phase shift and attenuation measurements at the receiver by synchronous detection. The lower frequency is used at the receiver to synchronize the receiver to the transmitter. The higher frequency signal is measurably affected by anomalies in the intervening geologic structure. The lower frequency signal is fixed low enough so it is not substantially affected by the intervening geologic structure. Geologic modeling tools are preferably downloaded by geoscientists to their personal computers. The total attenuation and phase shift measurements are plugged into a full-wave inversion code (FWIC) process.

Abstract: Most mines and underground facilities employ standardized construction techniques and materials. Such also cannot avoid having some above ground openings to receive utilities, fresh air, supplies, etc. Those or other surface openings are also universally used to discharge ground water, wastes, and other materials. Typical underground facilities have abundant electrical wiring and power demands, both of which can be detected at the surface. Levees with leakage pathways also form electrical conductors. When properly illuminated with remotely generated electromagnetic (EM) radiation, many of these features will “glow” or reradiate the radio energy in an electronic signature unique to the underground facility. Synchronized EM-gradiometer transponders are situated nearby on the ground surface to collect and analyze the “glow”. Alternative transmitting devices further includes ways to generate the illumination, and computers for characterizing the return signatures.

Abstract: A ground-penetrating radar comprises a single resonant microstrip patch antenna (RMPA) that is driven by a three-port directional coupler. A reflected-wave output port is buffered by a wideband isolation amplifier and a reflected-wave sample is analyzed to extract measured values of the real and imaginary parts of the load impedance-the driving point impedance of RMPA. Each such port will vary in a predictable way according to how deeply an object is buried in the soil. Calibration tables can be empirically derived. Reflections also occur at the interfaces of homogeneous layers of material in the soil. The reflected-wave signals are prevented from adversely affecting transmitted-signal sampling by putting another wideband isolation amplifier in front of the input port of the directional coupler. A suppressed-carrier version of the transmitted signal is mixed with the reflected-wave sample, and the carrier is removed.

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.

Abstract: A coal mining operation begins by using directional drilling to bore several horizontal shafts through a coal deposit with its natural overburden still intact. Any methane gas permeating the coal deposit is pumped out and preferably sold as natural gas to commercial and residential customers, or used locally in support of mining operations. The methane gas evacuation continues until the concentrations are reduced to safe levels for mining. But before mining begins, ground penetrating radar equipment is lowered into the boreholes for electronic imaging studies of the coal deposit. One borehole is used for a transmitter and another for a receiver. Many measurements are made at a variety of frequencies and equipment positions within the boreholes. Such studies estimate the electrical conductivity of the surrounding material, and thereby give clues where and how much coal is actually deposited.

Abstract: A coal mining operation begins by using directional drilling to bore several horizontal shafts through a coal deposit with its natural overburden still intact. Any methane gas permeating the coal deposit is pumped out and preferably sold as natural gas to commercial and residential customers, or used locally in support of mining operations. The methane gas evacuation continues until the concentrations are reduced to safe levels for mining. But before mining begins, ground penetrating radar equipment is lowered into the boreholes for electronic imaging studies of the coal deposit. One borehole is used for a transmitter and another for a receiver. Many measurements are made at a variety of frequencies and equipment positions within the boreholes. Such studies estimate the electrical conductivity of the surrounding material, and thereby give clues where and how much coal is actually deposited.

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.

Abstract: A landmine detection system comprises a ground-penetrating radar for probing the surface of the ground for landmines and other anomalies. The radar is swept back and forth across a lane while a user proceeds forward. A navigation sensor and processor keep track of all the parts of the lane that have been probed. A user display presents a visual graphic that represents the lane and the parts of it that have been probed. The user is then able to swing the radar to areas that are indicated as having been skipped in previous passes, e.g., to get 100%. coverage.

Abstract: A landmine detection system comprises a ground-penetrating radar for probing the surface of the ground for landmines and other anomalies. The radar is swept back and forth across a lane while a user proceeds forward. A navigation sensor and processor keep track of all the parts of the lane that have been probed. A user display presents a visual graphic that represents the lane and the parts of it that have been probed. The user is then able to swing the radar to areas that are indicated as having been skipped in previous passes, e.g., to get 100% coverage.

Abstract: A ground-penetrating radar comprises a single resonant microstrip patch antenna (RMPA) that is driven by a three-port directional coupler. A reflected-wave output port is buffered by a wideband isolation amplifier and a reflected-wave sample is analyzed to extract measured values of the real and imaginary parts of the load impedance-the driving point impedance of RMPA. Each such port will vary in a predictable way according to how deeply an object is buried in the soil. Calibration tables can be empirically derived. Reflections also occur at the interfaces of homogeneous layers of material in the soil. The reflected-wave signals are prevented from adversely affecting transmitted-signal sampling by putting another wideband isolation amplifier in front of the input port of the directional coupler. A suppressed-carrier version of the transmitted signal is mixed with the reflected-wave sample, and the carrier is removed.