MX2008007805A - Positioning system and method - Google Patents
Positioning system and methodInfo
- Publication number
- MX2008007805A MX2008007805A MXMX/A/2008/007805A MX2008007805A MX2008007805A MX 2008007805 A MX2008007805 A MX 2008007805A MX 2008007805 A MX2008007805 A MX 2008007805A MX 2008007805 A MX2008007805 A MX 2008007805A
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- positioning system
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Abstract
A positioning system designed to provide a three dimensional location of a object. The system can include one or more multiple transmitters or electromagnetic beacons, software defined radio receivers with an associated processing unit and data acquisition system, and magnetic antennas. The system applies theoretical calculation scale model testing, signal processing, and sensor data to operate.
Description
POSITIONING SYSTEM AND METHOD
FIELD OF THE INVENTION
The present invention relates generally to a method and apparatus pertaining to a positioning system. In particular, the invention relates to the determination of a three-dimensional location of an object.
BACKGROUND OF THE INVENTION
Geological mapping and geophysical surveying on the surface of the earth are mature sciences with a history of technology improvements that enhanced the fidelity of Earth's understanding, above and below the surface. However, when conventional techniques are used in an underground environment, geo-location has turned out to be a challenge that drives operational concepts to initialize techniques for geo-location of instrumentation and geological contacts and can actually limit the effectiveness of technologies employed. . Conventional surveying and mapping systems, such as a Global Positioning System
(GPS), determine the location of objects using satellite signals. However, there is a persistent problem with determining the location of personnel and equipment, for example, within underground facilities without the use of land surveying. To date, this problem has not been solved due to the difficulty in signaling / establishing communication between the surface of the Earth and underground installations / caverns / mines and the complexity of the electromagnetic propagation within the Earth. The very low frequency, lower fidelity systems are currently under development in Europe to support communications for cavern rescue operations. The systems only obtain a position of superficial depth when the communication system is used below the ground. These communication systems are effective up to 600 meters and occasionally at 1,200 meters. The systems are also used to locate the underground transmitters at comparable depths. In controlled experiments, these have achieved an accuracy of 2% in horizontal position and only 5% in depth.
SUMMARY OF THE INVENTION
The positioning system is the first practical means that will provide the location determination in the subsoil as well as provide a back channel communication capability of the low data rate. This development was made possible through the assembly of sensor technologies and processing capabilities that are currently evolving into the latest technology in several diverse arenas. In addition, due to the sensor technology used in the location of a position, the positioning system is not limited to being used in the subsoil. The development of the positioning system can provide individuals and equipment moving within a space, either above or below the ground, the ability to know its location in three dimensions. The positioning system finds the location of an object by applying theoretical calculations, testing scale models, and technology demonstrations including state-of-the-art signal processing, the fusion of multiple sensor data, and unique operating concepts. The invention provides a framework to demonstrate the feasibility of using multiple sensors and
phenomenologies using magnetic radio beacons and special Radio receivers with Software Defined to determine the location of an object, above or below the ground. A back channel communications capability is provided, both to support the operation of the positioning system and to provide low data rate communications between multiple locations in the subsoil and with surface assets. The existence of this return channel communication allows sharing the knowledge of the configuration of the underground space between multiple underground users and remote command elements as the subsoil is explored. A premise of an exemplary embodiment of the positioning system is to use multiple transmitters on the surface, in the vicinity of an underground space, to provide magnetic radio beacons. Signal processing can be supplemented by distant opportunity signals, both cooperatives such as the Active High-Frequency Aurora Research Program (HAARP) and non-cooperative such as low frequency and very low frequency communications / navigation systems and signaling signals. AM radio. The radio receiver with defined software taken to the subsoil can measure with
Precision the angles between the various transmitters (vectors that point back along magnetic field lines to surface beacons). Because the locations of the surface transmitter can be determined accurately when deployed and to which the magnetic radiation field can be calculated, the location of the underground receiver can be determined. This radio receiver with defined software and associated processing unit are compatible with existing ground navigation systems to provide a manual capacity that works both above and below ground level. An existing inertial guidance unit can be included as part of the processing unit to provide a stable reference as a provisional navigation capability for unique situations in which the adequate signal strength of the radio beacons is not available or if the sensor readings or beacon signal are excessively distorted by the underground infrastructure. In addition to the radio receiver with defined software and the inertial guidance unit, the invention can employ accelerometers / tilt measurement devices, magnetic compass, microbarograph, which oscillate in the return channel communications system, and
automated speed devices / control of the message chain. The positioning system provides navigation and surveying both above and below the ground and can be used in various geologies. In addition to the underground application, the positioning system has application to the problem of robust surface navigation.
BRIEF DESCRIPTION OF THE FIGURES
Figure 1 shows a positioning system architecture according to the invention. Figure 2 shows a positioning system according to an embodiment of the invention. Figure 3 shows an antenna according to an embodiment of the invention. Figure 4 shows a cube sensor used according to one embodiment of the invention. Figure 5 shows a 3-D address finding capability of very low / high cube frequency according to one embodiment of the invention. Figure 6 illustrates an analysis of a positioning system according to an embodiment of the
invention Figure 7 shows a positioning system according to an embodiment of the invention. Figure 8 shows a transceiver used according to an embodiment of the invention. Figure 9 shows coverage of the transmitter over an underground installation according to one embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
In the following detailed description, reference is made to the appended figures, which form part of the same and show, by way of illustration, specific modalities in which the invention can be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it will be understood that other modalities may be used, and that structural, logical as well as other changes may be made without departing from the spirit and scope of the invention. . The progress of the steps of the described process is exemplary of the embodiments of the invention; however, the sequence of steps is not limited to that stipulated here
and can be modified as is known in the art, with the exception of the steps that necessarily occur in a certain order. An exemplary positioning system 10 is shown in Figure 1. The positioning system has transmitter sites 12 and a receiving unit 14. As shown in Figure 1, the positioning system 10 involves the design and integration of a number. of components. The first components are magnetic surface beacons 10 which provide a continuous signal at different frequencies in the low / very low frequency range. Usually three to four (3-4) of these transmitters are required to support the positioning system in the various applications of the system, just as in its use in underground space. Additional opportunity signals from other transmitters in the very low / low / medium frequency range and AM radio signals can be exploited as additional signal sources. The second component is a sensitive three-component magnetic receiver 14 (radio) with the ability to precisely locate the magnetic vector emanating from surface radiobeacons. This radio receiver with defined software 14 incorporates a computational unit 15 with the capacity to process the data
from all transmitters, secondary sensors such as a magnetic compass, accelerometers, and clinometers to determine the orientation of the antenna, thus providing a three-dimensional location for the radio receiver with software defined 14 in the underground space, either above or under the ground. As shown in Figure 2, one embodiment according to the invention shows the radius with software defined 14 below the ground. This processing unit within the receiver 14 is designed so that existing ground navigation options are maintained for deployment and user interface. The underground locations obtained from the positioning system solution will change smoothly from certain GPS locations while the system remains above the surface of the Earth. Each transmitter radio beacon 12 may include a power supply, usually a battery pack 16 with the ability to hold the system for up to 30 hours or more, may be extended with additional batteries. The transmitter provides an adjustable frequency source and contains a GPS receiver 18 to determine the location of the transmitter package on the ground surface. The transmitting antenna can be a
Simple wire coil or a more complex system that uses a ferrite core. The positioning system employs paged beacon transmitters 12 for manual positioning while maintaining a consistent shape and fit configuration with beacons 12 that are being packaged for aerial launch or vehicle mounted. As shown in Figure 1, the defined software radio receiver 14 consists of a three-component RF magnetometer and a processing unit 15 with the ability to determine the azimuth and inclination of the vector magnetic fields induced by the radio beacon. By using the known locations of the cooperative transmitters 12 and azimuth for remote transmitters 12, the processing unit 15 determines the location of the receiver 17 on a continuous basis as the radio receiver with defined software 14 moves within the underground space. This processing unit 15 is interfaced to an existing GPS based ground navigation unit to provide full integration with databases and geographic surface information systems. In order to determine the strength of the transmitter 12, a source 1 A m2 is assumed and the fields in the
location received as a function of frequency (2 p?), depth (R) and soil conductivity (s). For a vertical magnetic dipole on the surface of the earth, the fields are completely described for the quasi-static case where the distance from the transmitter to the source is much less than a wavelength in the conduction medium (Earth). In this medium, the propagation constant is provided by equation 1:
? 2 =? 2μe + j? Μs (Equation i;
where μ and e are the permeability and permittivity of the medium. By definition, the wavelength in the driving medium is simply
1 / | ? | (Equation 2)
For conditions of: 10_1 < s < 104 mhos 100 < R < 1000 meters 100 < f < 106 hertz the main component of the magnetic field in the walls of the tunnel at the receiver's location is the vertical magnetic field, provided by the expression:
3me? H. = p? H Equation 3 '
where m is the magnetic dipole moment in Amp-m2. The realization of some basic assumptions for
typical operating conditions: s = 10"3 mhos f = 10,000 hz R = 100 and 300 meters Produces the following values for the field strength in the receiver:
R = 100 meters, Hz = 1.5xl0"3 fTesla R = 300 meters, Hz = 1.9xl01 fTesla The above values assume a dipole moment of the transmitter 1 A-m2.
The sensitivity of the ELF cube baseline antenna of 15.24 centimeters for the receiver is cited as dfTesla at 10 kHz. Assuming that this sensitivity is tangential (SNR = 66B), the invention uses a SNR of 20 dB, and band limit noise at 1 Hz to provide a satisfactory dynamic system response. The calculation of the required force of the transmitter 12 shows that the dipole moments used are 1.6 x 10-3 A-m2 at 100 meters depth, and 0.8 A-m2 at 300 meters depth. These are intensities of
easily generated signal in a relative manner in the range of 5 to 10 kHz. For example, the Zonge NT-20 TEM battery operated transmitter that drives a 1 m2 loop can easily generate a dipole moment of 25 A-m2. Much larger moments can be generated by this transmitter using a larger antenna. Figure 3 illustrates a dipole antenna 20 and a horizontal loop antenna 21. As shown in Figure 3, a compact antenna 20, 21 is preferred. A typical design would have the following characteristics: air core, 100 wire turns of aluminum # 4, thickness of two layers, radius of 0.1 m and height of 0.26 m. This antenna weighs approximately 3.7 kg and would have an input impedance at 10 kHz of 1 + J48O. To create a dipole moment 1 A-m2, this could be driven at 0.3 amps at an input power of 15 volts or 5 watts. An efficient Class D power amplifier could be used to produce the impulse signal with acceptable levels of harmonic distortion and efficiencies of 90%. Therefore, for approximately 6 watts of battery power, the transmitter could provide a constant CW transmitter signal. For a design that uses a 10S cell LiS02 primary battery that delivers 175 watt-hours at 15 volts, transmitter 12 could run in excess of 30 hours.
Each transmitter 12 can carry a GPS receiver
18 to be located at +/- lm. The coordinates will be transmitted as configuration data 22 to the software radio unit defined prior to entering the space, either above or below the ground. The antenna parameters 20, 21 will use optimization to minimize the power consumption and produce the largest transmitted dipole moment. The design of the amplifier electronics can be direct. The elements of the system including the time / phase synchronization associated with the rest of the system can be integrated into the design of the transmitter. For the final system, the packaging and complete integration of the components can use additional design engineering. A preferred antenna for use with this invention is the Raytheon Cube sensor 24, as shown in Figure 4, a triaxial air coil magnetic receiver that is currently one of the most sensitive instruments available with a 10 kHz noise floor. of 0.6 ftesla / sqrt Hz for the antenna of 30.48 centimeters and 5 ftesla / sqrt Hz for the antenna of 15.24 centimeters. By comparison, the manufacturers of Schlumberger EMI Technology Center developed a triaxial magnetometer widely used for geophysical applications that is
approximately 20db louder than the 15.24 centimeter cube sensor. Once the signals of the three orthogonal antennas are received by the defined software radius 14, they can be processed to determine the azimuth of the primary magnetic field vector of each transmitter as received. Figure 5 is an example of the energy distribution 26 for an elliptically polarized signal received by the Raytheon Cube 24. When executed in the positioning system 10, each channel corresponding to the transmission antennas 12 on the surface can be processed in This way to determine the solid angles between the vector fields of each transmitter 12. These vector fields can be corrected by the curvature of the lines of the magnetic field so that the location of the unit can be determined. In addition to signals from surface transmitters 12, other opportunity signals such as navigation beacons, very low frequency communication systems, and the High-Frequency Active Aurora Research Program (HAARP) may be used to provide restrictions. additional in the location.
A key to the accuracy of the location of the system 10 in one mode is the ability to understand and compensate for propagation anomalies in the medium between the surface transmitters and the underground receiver. Opportunity signals can be used to characterize the medium. Distant sources of opportunity signals can produce essentially uniform fields on the surface of the region around the operating area. These uniform fields can provide an excellent source of signals that can be measured at the receiver. By accurately measuring these signals, the effects of inhomogeneities in coating material can be calculated. These effects can then be used to adjust the measured direction of arrival of signals from the beacons of the surface transmitter 12 to a location of the more accurate prediction receiver 14. Figure 5 shows an elliptically polarized signal 28 and a signal power diagram received versus antenna orientation 26. The received signals are not expected to be as "clean" as shown in the example of Figure 5. It is anticipated that there will be multipath energy as well as secondary induced magnetic sources. However, this "" apparent parasite echo "can be discriminated from the primary field due to its signal characteristics and phase shift in
quadrature. In order to further restrict the location, additional sensors 30 (Figure 1) may be employed with the receiver 14 to provide independent information either to contribute directly to the location or to assist in the weighting of the contribution of beacon signals. Additional sensors 30 may include a magnetic compass, accelerometers / tilt measuring devices, a microbargraph, oscillating between relay cards of return channel communications, and a pedometer for the male package version and an odometer for a unit mounted on vehicle. The foundation for return channel and supplementary sensor communications will exploit micro-electromechanical sensor-based technologies. An inertial guidance system 19 (Figure 1) can be included in the design so that the positioning system 10 provides location information updated several times per second. This ensures smooth operation at times when the transmitters 12 are temporarily out of range or major anomalies of the receiver 14 occur which distort magnetic fields to negatively impact the calculated location. Figure 6 provides an error analysis for the positioning system. This analysis assumes that
there is a +/- 5 ° error in the measurement of the direction of the vector. Through integration and signal processing, this can be reduced to +/- 1 °. However, geological effects and the presence of anomalous secondary radiators will increase the uncertainty to approximately +/- 5 °. Through the use of precision frequency control and external synchronization of the beacons 12 and the receiver 14 through the initial establishment data and communications of the return channel, it is possible to reduce this final uncertainty by an additional factor that results in the predicted location uncertainty. Due to the curvature of the lines of the magnetic field 32 relative to the horizontal plane, it is anticipated that the real error ellipsis can be oriented along the vertical axis approximately 30% more than the horizontal axes. The positioning system 10 can use a distant but cooperative potential source to assist in the reduction of depth uncertainty. The highest power transmitters 12 can be used to excite a sweep frequency chirp or other multi-frequency signal. Due to the frequency dependence of the penetration depth of electromagnetic waves in the ground, the antenna of the
Subsurface reception positioning can detect the increased attenuation of higher frequencies within the chirp signal and thus provide additional restriction of receiver depth. In one embodiment of the invention, such as in Figure 7, the very low ground frequency receiver is based on the Raytheon 24 cube antenna that was described above. By notion, the vector output of this antenna 24 can be measured continuously as the user moves through the underground complex 34. Associated with the antenna can be found processing electronics that can calculate the direction of arrival of the magnetic fields received. Stored in the processor may be reference locations of each of the transmitters 12 as well as the information surveyed with respect to the opportunity signals. These can be used to calculate the user's current position. The GPS locations of the entry points will provide the "truth" for the starting positions. The outputs of the microbarometer can also be used to help provide incremental updating and error correction for elevation calculations. By using this data, the calculated location can be continuously updated on the GPS screen. An objective of one embodiment of the invention is
reduce the noise induced by movement below the noise floor of the system 10 for typical user movements. The frequency of operation helps in this problem, since the components of user noise induced at the operating frequency will be small. The design approach can take this into account to ensure that moving components in the very low frequency range of interest (-10kHz) are minimal. For example, the antenna can be enclosed in foam cushioning materials that substantially attenuate moving components in this range. This can be done with relatively small volumes of cushioning foam material. The invention can provide sufficient dynamic range at the antenna outputs so that the noise induced by the out-band movement (mainly in the extremely low frequency range) does not overload the electronic circuits. The baseline design also includes antenna tilt sensors to measure antenna movement. Solid state inclination sensors based on microelectromechanical sensors can be used for this purpose. With convenient movement information, adaptive filtering can be used to further reduce the effects of antenna movement. The complete protection with Faraday from the
antenna can be useful to reduce the potential interference from outside interference. The receiver may include an integrated return channel communications path that may allow the user to have elementary communications outside the subsoil location linked to traditional communication systems located near the entry point. As shown in Figure 8, one embodiment of the invention utilizes miniature disposable easily disguised ad hoc mesh-connected network transceivers 36 for this purpose. The network connection protocol allows the connection of automatic network, relay and update functions. The current 2.4 GHz base line radius 36 measures less than 21 x 27 x 6 mm including the antenna, or approximately the area of a postage stamp 38, which is illustrated in Figure 8. By concept, the user may release or place these small spokes 36 as a path of "bread crumbs" as you move along the tunnel or facility. When placed at corners or reactance points, radios 36 may communicate several hundred meters before another must be deployed. The very low frequency receiver will have one of these small communication transceivers built into the electronic circuits that communicates with the path of
"bread crumbles". At the other end of the road, a conventional communication transceiver can then be connected to the communication channels for the rest of the network that supports the operation. Small transceivers as they are currently designed are developed to send and receive data only. The very low frequency receiver has methods for the operator to easily and quickly enter coded commands that can be connected in relay to and from the communications network. A portable personal digital assistant or small manual can be used for this purpose. It is also possible to send and receive voice over this same network either intermittently or continuously. Users can not only determine their own position, but also send their position to the rest of the operations team. Similarly, they can also receive through the same network the locations of other users on the computer as they report their positions. In traditional geophysical surveying using electromagnetic approaches, the presence of conductors near the source and the receiver can be minimized through careful collection planning. However, in the positioning system, the anticipation of operational sites may have surface conductors near the locations in
where the transmitters 12 are deployed, that these conductors in the form of tubes, tunnel cover, and holes will be present through the operated area, and that there will be conductors in the near field of the receiver 14 in the sub-floor. All of these are problematic and represent an important source of "clutter" or noise which can impede the proper operation of the positioning system 10. The invention addresses all of these functional elements: validation of theoretical models; development of magnetic field templates, to support the location algorithms; and development of automated procedures to separate the parasitic echo from the direct transmitted signals. For the positioning aspects of this system, this natural and man-made "echo parasite" is a potential obstacle to the performance of the positioning system 10. In another potential application of this system, the "parasitic echo" is actually a source useful signal which can be analyzed to reveal significant or important information regarding the composition of the material and / or hydrology of the land within the volume of influence of the beacons of the positioning system 12. Different different means are possible to alter the behavior and performance of the positioning system 10 to drive the
investigation of the geophysical properties of sub-surface materials. Multiple surface transmitters / beacons 12 in extremely low / very low / low frequency ranges are used as radiobeacons in the radiofrequency magnetic field. Depending on the desired information and the availability of specific access, similar beacons are also used within the underground space and in vertical and / or horizontal holes. The locations and orientations of beacon 12 are passed through a radio frequency link to an underground receiving unit 14 as "configuration data" 23 before the unit goes underground. The underground receiving unit 14 can also be used above the ground and / or in vertical or horizontal holes to improve the collections of geophysical signatures. Additional sensors are included in the receiving unit to include, but are not limited to, magnetic compass, magnetometers, microbarographs, and accelerometers. Additional geophysical sensors can be deployed simultaneously to assist in interpretation. A general perspective of the concept of the positioning system 10 of operations is described in the following paragraphs. The positioning system 10
It can have a short configuration time, it can be easily operated by personnel in the field, and it supports the capacity for worldwide deployment. System 10 consists of reinforced magnetic transmitters (radio beacons) 12 operating in the very low / low frequency range. The system can be delivered by air or through manual means and is not affected by the closest structures. A magnetic antenna is used in the subsoil to receive signals from transmitters 12 on the surface. The defined software radio receiver 14 has a manual screen and can be set by man or mounted on all-terrain vehicles as the situation dictates. The development of electromagnetic transmitters 12 can be performed in various ways. The transmitter 12 can be thrown into the air by a fixed-wing aircraft, rotating aircraft or manually deployed. An all-terrain vehicle may be used to place the beacon 12 transmitters in the desired location providing the optimum superposition pattern. The transmitters 12 should be placed in such a manner that at least three of the signals 40, 40 ', 40"overlap each other in the effective beacon range, as shown in Figure 9. To ensure adequate coverage of the range of radio beacon
transmitter, signal emissions 40, 40 ', 40"can form an umbrella over the target area To initiate the use of positioning system 10, field personnel can be synchronized with transmitters 12 that verify connectivity by signal deployment in manual receivers The locations and orientation of the transmitter 12 are sent to the receiver 14 prior to entering an underground facility The operator can ensure that the receiver 14 initializes with the transmitters 12 before going underground and that the track record is operational An operations center located off-site, but close to the application site could monitor the current position of the receivers of the underground positioning system 14. The receiver of the positioning system 14 can be mounted on an all-terrain vehicle or used in A backpack The receiver uses the radio beacon signals 12 to geo-locate itself inside the subsoil. 14 reinforced manual navigation can display the current grid location, portation, trajectory tracking, critical reference points of interest, and battery life. The receiver 14 can be a controllable operator, back lighting, platform based on the drilling menu. It can easily be
navigate in the menus and these are user friendly. By blocking GPS, the transmitter 12 will begin to emit signals of location and orientation to the receiver 14. The receiver 14 can easily be reconfigured from the man-made mode to the ATV configuration. All necessary accessories are compatible with any configuration. Transmitters 12 and receivers 14 can have an active life cycle of up to 30 or more continuous operating hours, being able to extend with additional batteries. In the case that field operations exceed the life cycle, batteries can be replaced manually or new transmitters can be deployed 12. An internal memory battery 42 (figure 1) can prevent data loss in the event of failure of the primary battery. To conserve battery power 42 and limit operational signature, programmable time delay and wake-up ability can be used when transmitters are deployed prior to operations. Once each transmitter 12 is placed and activated, these can be turned on and auto-located by the use of a Global Positioning System 10. A return channel communication link using disposable relay cards, "crumbs of
The "bread crumbs" can be used to establish communication with the surface transmitter / receiver and other operational elements.These "bread crumbs" can provide site line data relay along the tunnels. A network capable of transmitting data between the units that are above the ground and below the ground The receiver 14 may have the capability to send communications of low data transfer rate to the receiver above ground. Remote control center tracks the location of the receivers of the underground positioning system 14 and communicates with each receiver operator.The underground navigation and mapping can be executed in multiple ways.In the backpack configuration, a single operator can operate and charging the receiver 14 while exploring the underground environment.With the receiver 14 mounted on a vehicle, the vehicle operator can operate the hands-free positioning system 10 while the data is sent to the receiver of the surface. The manual receiver 14 can be attached to the operator's equipment. The mobile control center can have the same graphic representation of the underground navigation and mapping as the underground operator. Beyond geophysical exploration, other
Potential applications of the positioning system concept 10 include the remote geodesy of abandoned underground mines, exploration of natural caverns and geodesy, and rescue of mines and underground caverns. Furthermore, the invention is not limited to underground applications but can be applied to a variety of environments, including above-ground locations. The processes and devices described above illustrate preferred methods and typical devices of many that could be used and produced. The above description and the figures illustrate modalities, which achieve the objectives, characteristics and advantages of the present invention. However, it is not intended that the present invention be strictly limited to the modalities described above and illustrated. Any modification, although currently unpredictable, of the present invention that is within the spirit and scope of the following claims should be considered part of the present invention.
Claims (50)
- NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, the content of the following is claimed as a priority: CLAIMS 1. - A positioning system comprising: at least two electromagnetic radio beacons; a sensor that measures instantaneous vector values of the magnetic field produced by the radio beacons; a processing algorithm that calculates a position of the sensor and based on the values and orientations of the magnetic vectors; at least one data acquisition system and computing devices that execute the algorithm; and at least one unit that displays navigation information to an operator. 2. - The positioning system according to claim 1, characterized in that the algorithm comprises measurements of the magnetic field vector of the local earth and direction of gravity to improve the accuracy of navigation. 3. - The system of positioning of conformity with claim 1, characterized in that the algorithm comprises additional opportunity signals from the transmitters in the very low / low / medium frequency range and AM radio signals to improve the navigation accuracy. 4. The positioning system according to claim 1, characterized in that the algorithm comprises signals coming from a navigation system by inertia, atmospheric pressure altimeters, and odometers that measure a displaced total distance to improve the navigation precision. 5. The positioning system according to claim 1, characterized in that the algorithm comprises signals from a network of transceivers placed between a navigation system and a location where there is a reference to an external navigation system to improve the accuracy of navigation. 6. The positioning system according to claim 1, wherein the algorithm comprises signals from all sources in claims 2-5 to improve the accuracy of navigation. 7. The positioning system according to claim 1, characterized in that the electromagnetic radiobeacons are magnetic coils with or without a ferromagnetic core having a well-characterized spatial distribution of the magnetic field with respect to a body of the radio beacon. 8. The positioning system according to claim 7, characterized in that the electromagnetic beacons can measure their own position and orientation in an external coordinate system and communicate that information to the computing devices that execute the navigation algorithm to transform the distribution of the spatial magnetic field in the spatial distribution with respect to the external coordinate system. 9. The positioning system according to claim 7, characterized in that the electromagnetic beacons can measure their position and physically change their orientation in space and, therefore, change the orientation of their magnetic field in an external coordinate system and communicate that information to the computing devices that execute the navigation algorithm to transform the spatial distribution of the magnetic field into the spatial distribution with respect to the external coordinate system. 10. The positioning system according to claim 7, characterized in that the electromagnetic radio beacons control a field electromagnetic emitting by reference to an internal clock and can synchronize the internal clocks with each other and with an internal clock of the magnetic field sensor and / or the data acquisition systems. 11. The positioning system according to claim 10, characterized in that the radio beacons synchronize the internal clocks, with respect to any signal of opportunity, before deployment in a field and maintain the synchronization maintaining the accuracy of the clocks. 12. The positioning system according to claim 10, which also includes radio beacons and data acquisition systems that synchronize internal clocks using the very low frequency signals generated by the radio beacons or by other cooperative sources. 13. The positioning system according to claim 10, further comprising radio beacons that radiate signals at exactly the same frequency or fractional frequency, such as the beacon frequency ratios of 1: 1, 1: 2, 2: 3, and 3: 4. 14. The positioning system according to claim 1, characterized in that the processing algorithm improves the accuracy of the navigation data by correcting local magnetic anomalies. 15. - The positioning system according to claim 14, further comprising the processing algorithm that characterizes the local magnetic anomalies by comparing the true geographic North-South direction as measured by a gyro compass with the magnetic North as measured. by the magnetic compass. 16. The positioning system according to claim 14, characterized in that the processing algorithm characterizes the local magnetic anomalies by comparing the true vertical direction as measured by an inclinometer and an electromagnetic vertical as measured by a propagation direction. of a flat electromagnetic wave from a cooperative source. 17. The positioning system according to claim 14, characterized in that the processing algorithm characterizes the local magnetic anomalies by comparing the true geographic East-West direction as measured by a gyro compass and the magnetic "East" created by a artificial magnetic dipole placed near a navigation site. 18. The positioning system according to claim 17, characterized in that the artificial magnetic dipole is formed by two or more radio beacons synchronized ones placed in a close horizontal orientation near a navigation site that are separated by a relatively large distance and are oriented in a direction that is not parallel to the North-South. 19. The positioning system according to claim 14, characterized in that the processing algorithm characterizes the local magnetic anomalies by comparing the directions of the magnetic fields produced by the navigation radio beacons and measured by the magnetic field sensor versus the coordinates. actual magnetic field sensor as measured by other devices such as a GPS when the magnetic field sensor is above the ground, or by positioning the magnetic field sensor on known landmarks or other triangulated points. 20. The positioning system according to claim 14, characterized in that the processing algorithm determines local magnetic anomalies by measuring the magnetic field in multiple positions with known geographical coordinates above or below the ground. 21. The positioning system according to claim 20, characterized in that the above-ground measurements are made in the processing algorithm so that the positions can be measures independently with respect to a GPS or a similar navigation system. 22. The positioning system according to claim 20, characterized in that the characterization of the magnetic anomalies is performed using a magnetic field sensor associated with the data acquisition and computation system, but the characterization thus derived is used by all the magnetic field sensors with their data acquisition systems and their computing devices and screens. 23. The positioning system according to claim 1, characterized in that the radio beacons of claim 13 that change their frequencies in a predetermined manner to form temporary artificial beacons of claim 17. 24.- The positioning system in accordance with claim 13, characterized in that the radio beacons transmit at 2 or more frequencies so that one of these signals forms the artificial dipoles of claim 27 while the other frequencies do not, but form a pulse frequency signal. 25. The positioning system according to claim 10, characterized in that the data acquisition system executes the synchronous detection of the signals coming from the radio beacons, synchronous detection occurs where the measured signal received by the magnetic field sensor is correlated with a profile that depends on the expected time of the signal that is generated based on a synchronization clock, the detection is made by maximizing the signals in phase and minimizing the out-of-phase and random signals. 26. The positioning system according to claim 25, characterized in that the synchronous detection comprises that the signal generated by the radiobeacons has frequency ratios in fractions. 27. The positioning system according to claim 25, further comprising the synchronous detection wherein each of the frequencies of all the radio beacons changes in a predetermined pseudo-random manner. 28. The positioning system according to claim 25, which also comprises the synchronous detection of the place where some of the radio beacons transmit at various frequencies simultaneously. 29. The positioning system according to claim 1, characterized in that the beacon signals are modulated to transmit information to the deployment units. 30.- The system of positioning of conformity with claim 1, characterized in that the magnetic field sensor is based on a coiled antenna comprising at least 3 coils of wire with orientations that are not parallel to a single plane. 31.- The positioning system according to claim 1, characterized in that the magnetic field sensor is based on a magnetic ferrite antenna placed in a vicinity of a magnetic field sensitive element, such as a coil, a flow gate , a magnetoresistor, a Hall effect sensor, and a superconduction quantum interference device magnetometer. 32. The positioning system according to claim 31, characterized in that the ferrite magnetic antenna is formed by a rectangular piece of material of high magnetic permeability with a high length-to-diameter ratio. 33. The positioning system according to claim 7, characterized in that the radio beacons communicate information unrelated to the navigation of navigation devices. 34.- The positioning system according to claim 33, characterized in that the communication system uses harmonic or sub-harmonic frequencies, where the use of the frequencies facilitates the synchronous detection of the radio beacon system to communicate information unrelated to the navigation of the navigation devices. The positioning system according to claim 14, characterized in that the algorithm uses magnetic anomalies to determine the geological and hydrological characteristics of the means and characteristics of man-made structures surrounding the magnetic field sensor. 36. The positioning system according to claim 14, characterized in that the navigation system has an ability to measure electromagnetic radiation at frequencies other than those used for navigation that can be initiated by other sources. 37.- The positioning system according to claim 36, characterized in that the navigation system combines the navigation data and the non-navigational electromagnetic data to determine the geological and hydrological characteristics of the means and characteristics of structures made by the man surrounding the magnetic field sensor. 38.- The positioning system according to claim 1, characterized in that the navigation system uses the radio beacons to transmit electromagnetic radiation that is used for geological and hydrological characterization. 39.- The positioning system according to claim 38, characterized in that the navigation system uses the electromagnetic signal in multiple spectral regions for navigation and characterization of a sub-surface geophysical environment. The positioning system according to claim 35, characterized in that the navigation system algorithm uses the radio beacon of claim 8 with known locations to characterize other RF sources. 41. The positioning system according to claim 30, characterized in that the navigation system uses at least one coil of the coil antenna to transmit information to a surface. 42. The positioning system according to claim 41, characterized in that the navigation system uses the radio beacons as receivers for the signal transmitted by the coil antenna. 43.- The positioning system according to claim 7, characterized in that the radio beacon comprises the coil wound around a ferromagnetic sphere and digitally controlled circuits with a synchronized clock are designed to introduce a current in the coil. 44.- The positioning system according to claim 43, characterized in that the coil is placed either around a larger cross section of a sphere, or uniformly around the sphere, or some intermediate partial coverage of the sphere. 45.- The positioning system according to claim 7, characterized in that the algorithm uses effects of known geological and hydrological characteristics to improve the navigation precision. 46.- The positioning system according to claim 45, characterized in that the algorithm can optimize a location of the radio beacons for better navigation results. 47.- The positioning system according to claim 7, characterized in that the beacon can be moved in a predetermined manner to improve a navigation and / or a geological characterization of a site. 48. The positioning system according to claim 7, characterized in that the beacon can scan a space in a predetermined way to improve a navigation and / or a geological characterization of a site, the exploration is a C exploration or conical exploration. 49. - The positioning system according to claim 7, characterized in that a delivery and placement of the beacon use manual positioning, parachutes, and penetrometers, the penetrometers are a delivery system comprising a large diameter penetrometer that encloses the entire the radio beacon and a small diameter penetrometer that are attached to the beacon and used as a mount. 50.- The positioning system according to claim 48, characterized in that the radio beacons are located on board stationary and moving vehicles, helicopters and drones.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US60/750,787 | 2005-12-16 |
Publications (1)
Publication Number | Publication Date |
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MX2008007805A true MX2008007805A (en) | 2008-09-26 |
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