RU2543521C1 - Method and system for multifrequency positioning in shielded space - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: method comprises simultaneously receiving positioning signals for bandwidths of satellite navigation systems: L1 GPS, L1 GLONASS, L2 GPS, L2 GLONASS, L3 GLONASS, L5 GPS. Each used signal is re-emitted by a separate frequency-selective relay which selects, using a band-pass filter, only the bandwidth used by a receiving and a radiating antenna. The method includes simultaneously obtaining digital information from all received positioning signals; simultaneously calculating coordinates and current time for each of the received bandwidths of the satellite navigation systems; the obtained different coordinates correspond to coordinates of receiving antennae, and the time obtained when calculating each coordinate is equal to the sum of the delay time in the relay and the propagation time of the signal from the emitter to the receiver; comparing the obtained coordinates for each bandwidth of the corresponding satellite navigation system; the divergence of coordinates indicates that a multifrequency receiver is located in shielded space; solving the task of determining the position of the antenna of the multifrequency receiver.

EFFECT: high accuracy of positioning in shielded space.

7 cl, 1 dwg

Description

The invention relates to satellite navigation systems (SNA) positioning, in particular to the provision of positional information in places beyond the reach of radio signals SNA GPS, GLONASS, Galileo, Compass, GAGAN, QZSS, and can be used in positioning systems in a shielded space, for example, in underground passages , metro stations, indoors, tunnels, gorges, etc.

SNA, such as GPS, GLONASS, Galileo, Compass, GAGAN, are used globally by users to determine their location in space. Each SNA includes a series of navigation spacecraft (NSC) orbiting around the Earth, and each NSC transmits radio signals with navigation messages containing ephemeris information with time stamps and an almanac.

Using the information of navigation messages received by the navigation equipment of consumers (NAP), in particular, the receiver of SNA signals, and measuring the pseudorange to several selected satellite, establish functional relationships between the known coordinates of the satellite and the unknown coordinates of the users of the SNA. Assessment of user coordinates is reduced to solving a navigation problem.

Often, the signals emitted by the SNA NSA cannot be received using NAP, due to various obstacles, for example, indoors or in shielded spaces.

A technical solution is known (1 analogue) - the method and positioning system, patent of the Russian Federation for invention No. 2161318 dated 12/27/2000, which offers a system and method for determining the position for use in a shielded space. The system includes a GPS receiver for receiving GPS signals and transmitting navigation data, a clock synchronization recovery unit for receiving navigation data and restoring an accurate time signal, a computer processor for obtaining an accurate time signal and navigation data, and at least four pseudo-satellites, installed inside a shielded space, and at least one of the four pseudosatellites is not coplanar relative to the others. A method for providing an internal positioning system includes the following steps: obtaining GPS signals, reconstructing an accurate time signal from GPS signals, calculating orbital parameters for at least four pseudo-satellites, and transmitting pseudo-satellite data signals using the reconstructed time signal and orbital parameters for at least , four pseudo-satellites, generating navigation data information (NAVDAT) from the received GPS signals, using navigation data information (NAVDAT) to calculate bit parameters of pseudo-satellites and the inclusion of an offset in the navigation information (NAVDAT) when calculating orbital parameters, additionally includes a delay in the reconstructed time signal to account for different signal travel times to each of the pseudo-satellites. The disadvantage of this technical solution is that the positioning system receives pseudosatellite signals of one SNA (GPS), while it is necessary to use a SNA signal receiver with specialized software for processing pseudosatellite signals. Another disadvantage is the complexity of the system, which increases the time to obtain a solution to the navigation problem, and the difficulty of ensuring high positioning accuracy.

A technical solution is known (2 analogs) - a system and method for a GPS repeater ("SYSTEM AND METHOD FOR GLOBAL POSITIONING SYSTEM REPEATER"), US application for invention No. 20060208946 of 09.21.2006, which contains a directional receiving antenna for receiving GPS signals from one or more satellites in a pre-selected area of the sky, a transmitting antenna for transmitting the received GPS signals, and a radio frequency amplifier, to increase the gain level of the received GPS signals before transmitting to the room. One or more of these GPS repeaters are used to play satellite constellations inside buildings or underground to provide GPS coverage in these environments. The disadvantage of this technical solution is the use of signals from one SNA (GPS), moreover, the system described in the invention uses directional receiving antennas covering various segments of the celestial hemisphere. This technical solution does not have high positioning accuracy.

A technical solution is known (3 analogs) - a system for providing positional information, a device and a transmitter for providing positional information, a patent of the Russian Federation for invention No. 2440590 of 05/10/2010, which allows you to provide positional information without loss of accuracy even in places beyond the reach of radio signals from the NCA, provides the need for time synchronization with the NCA. To this end, the process performed using the positional information providing device includes the steps of: receiving the received positioning signal, specifying the radiation source of the positioning signal, receiving, when the radiation source of the positioning signal is outside, a navigation message included in the positioning signal, performing the process, designed to calculate the position based on the signal, when the radiation source of the positioning signal is inside scheniya, message data from the positioning signal, obtaining coordinate values from the data and displaying positional information based on the coordinate values. The disadvantage of this invention is that the received signals from the NSC are subjected to modification in the transmitting device, and this complicates the construction of the NAP, in particular the SNA signal receiver, and increases the time for obtaining a solution to the navigation problem.

As a prototype, an indoor positioning system based on global positioning system (GPS) signals and pseudosatellites with external directional antennas (“INDOOR POSITIONING SYSTEM BASED ON GPS SIGNALS AND PSEUDOLITES WITH OUTDOOR DIRECTIONAL ANTENNAS”), international patent application No. 20111080541 dated 07.07. 2011. This invention comprises three GPS receiving antennas for receiving GPS signals originating from at least three GPS satellites, at least three radio frequency (RF) GPS relays designed to amplify GPS signals x of directional GPS receiving antennas, the RF GPS repeater consisting of a bandpass filter to reduce noise, a low noise amplifier to amplify the GPS signal, a transmission line for transmitting signals from GPS receiving antennas to GPS emitting antennas, at least three GPS radiating antennas, for transmitting GPS signals from RF GPS repeaters to shielded space, at least one GPS receiver for receiving GPS signals from GPS radiating antennas, GPS receiver antenna and method for determining positioning, which includes the following operations: receiving GPS satellite positioning signals (pseudorange and digital information), receiving data from a positioning signal (digital information) about the position of each satellite, processing navigation messages, calculating position (coordinates) and UTC (Coordinated Universal Time ) GPS NAP.

The disadvantage of this invention is that when it enters the shielded space, the GPS receiver must obtain data on the location of the emitting antennas (pseudosatellites) or extract information about their location from the received signal. At the same time, the satellite’s orbit data obtained by the GPS signal receiver while in the external navigation field are not used in any way, so there will definitely be a break in determining the position. This is one of the important deterrents to the widespread use of pseudosatellites.

The objective of the invention is to increase the accuracy of positioning in a shielded space using signals from the SNA, for example, GPS, GLONASS, Galileo, Compass, GAGAN.

An additional objective of the invention is the creation of a method and system that will allow you to create a navigation field corresponding to the external navigation field and provide a continuous solution to the navigation problem when moving from an external navigation field to the inside of the shielded space.

Another additional objective of the present invention is to increase the number of situations in which the method and system of multi-frequency positioning in a shielded space based on SNA positioning and positioning can be used.

The tasks are solved due to the fact that in the method of multi-frequency positioning in a shielded space, they simultaneously receive positioning signals for the SNS frequency ranges: L1 GPS, L1 GLONASS, L2 GPS, L2 GLONASS, L3 GLONASS, L5 GPS, while the frequency range L1 GPS can be replaced by the Galileo L1 frequency range, and the GPS L5 frequency range on the Galileo E5a; moreover, each of the signals used is re-emitted by a separate frequency-selective repeater that selects only the used frequency band, receiving and emitting antenna with a band-pass filter; simultaneously receive digital information from all received positioning signals; simultaneously calculate the position (coordinates) and current time UTC separately for each of the accepted SNA frequency ranges: L1 GPS, L1 GLONASS, L2 GPS, L2 GLONASS, L3 GLONASS, L5 GPS, while the frequency range L1 GPS can be replaced by the frequency range L1 Galileo, the frequency range L5 GPS on E5a Galileo, and the different coordinates obtained correspond to the coordinates of the receiving antennas, and the time obtained in the process of calculating each coordinate is equal to the sum of the UTC time, the delay time in the repeater and the propagation time of the signal from the emitter to the receiver; moreover, to increase the accuracy of positioning, the propagation time of the signal from the receiving to the transmitting antenna is leveled by any of the known methods (for example, selecting the cable length); comparing the obtained coordinates for each range of the corresponding SNA, and the coincidence of the coordinates corresponds to the fact that the multi-frequency receiver is in the external real navigation field, and the difference of coordinates corresponds to the fact that the multi-frequency receiver is located in the shielded space; they solve the problem of determining the position of the antenna of a multi-frequency receiver, and for this, the coordinates of the radiating antennas that correspond to the coordinates obtained for each frequency range of the corresponding SNA and the time difference between the antennas are used.

This method is implemented by a multi-frequency positioning system in a shielded space in which the repeaters are frequency-selective, each of the signals being used is re-emitted by a separate frequency-selective repeater, which selects only the used frequency band, the receiving and radiating antennas, and the radiating antennas are located in different places of the shielded room coaxially with receiving antennas, the SNA signal receiver is multisystem with the ability receiving SNA signals in at least three different frequency ranges from the following set: L1 GPS, L1 GLONASS, L2 GPS, L2 GLONASS, L3 GLONASS, L5 GPS and provides the determination of coordinates and time separately and simultaneously for each of the received frequency ranges.

Also, in the frequency-selective repeaters of the system, the L1 GPS frequency range transmit-receive can be replaced by L1 Galileo, and L5 GPS by E5a Galileo.

Also in frequency selective repeaters of the system, the filter bandwidths emitting the operating frequency range should not overlap in frequency.

Also in the system, the receiving antennas and the emitting antennas of the SNA signals have the same coordinates, respectively, and the propagation time of the signal from the receiving to the emitting antenna is the same.

Also in the receiver of signals of the SNA system, the frequency range L1 GPS can be replaced by the frequency range L1 Galileo, and the frequency range L5 GPS by the frequency range E5a Galileo.

Also, the signal receiver of the SNA system is configured to solve the navigation problem by the difference in the propagation time of the SNA signal from radiating antennas located at least at three different points in the screened space.

The shielded space of the system has dimensions that are many times greater than the wavelength of the signals used by the spacecraft, and the radiating antennas are located in the upper part of the shielded space at the maximum distance from each other.

The technical result is to increase the accuracy of positioning in shielded space using SNA signals, for example, GPS, GLONASS, Galileo, Compass, GAGAN and to provide a continuous solution to the navigation problem when moving from the external navigation field of the SNA to the inside of shielded space using a multi-frequency positioning system in shielded space.

An additional technical result is to obtain positioning coordinates without using any data sources about radiating antennas in a shielded space, including databases.

An additional technical result is the expansion of the scope of multi-frequency and multi-system NAPs, namely, it allows the use of conventional multi-system, multi-frequency receivers of SNA signals for positioning in a shielded space, without changing their structure.

An additional technical result is the use of the same NSA SNA signals (pseudorange, digital information) for positioning outside and inside the shielded space.

An additional technical result is an increase in the number of situations in which global navigation positioning systems can be used.

Figure 1 shows the structural diagram of a multi-frequency positioning system in a shielded space, which contains 1, 4, 7 - receiving antennas, 2, 5, 8 - bandpass filters, 3, 6, 9 - low noise amplifiers, 10 - shielded space, 11, 12, 13 - radiating antennas, 14 - multi-frequency receiver of SNA signals, 15 - antenna of a multi-frequency receiver of SNA signals.

The method and system of multi-frequency positioning in a shielded space are implemented as follows.

In the shielded space (10), which has dimensions many times greater than the wavelength of the used SNA signals, in the upper part, at a maximum distance from each other, there are emitting antennas (11, 12 and 13) in an amount of at least three. Each radiating antenna is connected, through a transmission line, the length of which is selected in such a way as to ensure the same delay of the signals from the receiving to the transmitting antenna, the corresponding frequency-selective repeater. The repeater consists of a low-noise amplifier, respectively (3, 6, 9), the gain of which is selected in such a way as to compensate for the path loss from the receiving antenna (1, 4, 7) to the radiating antenna (11, 12, 13), and a band-pass filter ( 2, 5, 8), which makes it possible to single out one of the frequency ranges of the SNA, for example, L1 GLONASS, or L1 GPS, or L2 GLONASS, or L2 GPS. Bandpass filters are connected to receiving antennas, respectively.

The SNA signal receiver (14) with the SNA signal receiver antenna (15), falling into the navigation field thus formed, will receive different coordinates for the selected frequency ranges and SNA corresponding to the phase centers of the corresponding receiving antennas. At the same time, as a result of solving the navigation problem, a different path length will be obtained from the radiating antenna to the SNA signal receiver. Knowing the path length and the coordinates of the emitting antennas, the problem of positioning the antenna of the SNA signal receiver is solved by the method of multi-frequency positioning in a shielded space. This method allows the use of conventional multisystem, multi-frequency receivers of SNA signals for positioning in a shielded space, without changing their structure.

The CMC signal receiver provides the determination of coordinates and time for each of the received frequency ranges, and also provides a solution to the navigation problem by the difference in the propagation time of the signal from the radiating antennas located at least three different points of the shielded space.

The antennas for receiving and emitting GNSS signals are a broadband antenna with a range of operating frequencies from 1.1 GHz to 1.67 GHz.

A frequency selective repeater consists of a band-pass filter, a low-noise amplifier and a transmission line, and the band-pass filters are filters with the following characteristics: attenuation in the working frequency band no more than 3 dB, outside the working frequency band more than 40 dB, and low-noise amplifiers are low-noise amplifiers with amplification from 10 to 40 dB (depending on the length of the transmitting path).

The navigation receiver for receiving SNA signals is any multi-frequency satellite receiver of SNA signals, for example, PSNM, developed by ZAO KB NAVIS.

Shielded space - a space in which GPS, GLONASS, Galileo, Compass, GAGAN GPS signals are not available for reception.

The transmission line is an RF connection cable.

This technical solution can be used in positional orientation systems of moving objects of various physical nature inside a shielded space using a conventional multi-frequency receiver of SNA signals for positioning without changing their structure, for example, in underground passages, metro stations, indoors, tunnels, gorges, etc.

Claims (7)

1. A method of multi-frequency positioning in a shielded space, including receiving GPS positioning signals (GPS) in the form of pseudorange and digital information, receiving data from a positioning signal in the form of digital information about the position of each satellite, processing navigation messages, calculating position (coordinates) and UTC (Coordinated Universal Time) GPS time of navigation equipment of consumers (NAP), characterized in that they simultaneously receive signals positioning for the SNS frequency ranges: L1 GPS, L1 GLONASS, L2 GPS, L2 GLONASS, L3 GLONASS, L5 GPS, while the frequency range L1 GPS, for example, is replaced with the frequency range L1 Galileo, and the frequency range L5 GPS with E5a Galileo; moreover, each of the signals used is re-emitted by a separate frequency-selective repeater that selects only the used frequency band, receiving and emitting antenna with a band-pass filter; simultaneously receive digital information from all received positioning signals; simultaneously calculate the position in the form of coordinates and the current time UTC separately for each of the accepted SNA frequency ranges: L1 GPS, L1 GLONASS, L2 GPS, L2 GLONASS, L3 GLONASS, L5 GPS, for example, the frequency range L1 GPS, for example, is replaced by a frequency range L1 Galileo, the frequency range L5 GPS on E5a Galileo, and the received different coordinates correspond to the coordinates of the receiving antennas, and the time obtained in the process of calculating each coordinate is equal to the sum of the UTC time, the delay time in the repeater and the propagation time of the signal from the emitter to the receiver; moreover, to improve positioning accuracy, the propagation delay of the signal from the receiving to the transmitting antenna is aligned; comparing the obtained coordinates for each range of the corresponding SNA, and the coincidence of the coordinates corresponds to the fact that the multi-frequency receiver is in the external real navigation field, and the difference of coordinates corresponds to the fact that the multi-frequency receiver is located in the shielded space; solve the problem of determining the position of the antenna of the multi-frequency receiver, and for this, the coordinates of the radiating antennas are used, which correspond to the coordinates obtained for each frequency range of the corresponding SNA, and the difference in the propagation time of the signals between the radiating antennas. 2. A multi-frequency positioning system in a shielded space, containing three GPS receiving antennas, designed to receive GPS signals from at least three GPS satellites, at least three radio frequency (RF) GPS repeaters, designed to amplify GPS signals, outgoing from directional GPS receiving antennas, the RF GPS repeater consists of a bandpass filter to reduce noise, a low-noise amplifier to amplify the GPS signal, a transmission line for transmitting signals from GPS receiving antennas to radiating m GPS antennas, at least three GPS emitting antennas designed to transmit GPS signals coming from RF GPS repeaters to a shielded space, at least one GPS receiver designed to receive GPS signals coming from GPS emitting antennas, GPS antenna a receiver, characterized in that the repeaters are frequency-selective, each of which provides reception and transmission of one frequency range of the SNA: L1 GPS, or L1 GLONASS, or L2 GPS, or L2 GLONASS, or L3 GLONASS, or L5 GPS, respectively, emitting en the tents are located in different places of the shielded room coaxially with the receiving antennas, the SNA signal receiver is multisystem capable of receiving SNA signals in at least three different frequency ranges from the following set: L1 GPS, L1 GLONASS, L2 GPS, L2 GLONASS, L3 GLONASS , L5 GPS and provides the determination of coordinates and time separately and simultaneously for each of the received frequency ranges. 3. The multi-frequency positioning system in the shielded space according to claim 2, characterized in that in frequency selective transponders the transmit-receive frequency range of the L1 GPS, for example, is replaced by L1 Galileo, and L5 GPS by E5a Galileo. 4. The multi-frequency positioning system in the shielded space according to claim 2, characterized in that in the frequency-selective repeaters of the system, the passband of the bandpass filters that select the operating frequency range do not intersect in frequency. 5. The multi-frequency positioning system in the shielded space according to claim 2, characterized in that the receiving antennas and emitting antennas of the SNA signals have the same coordinates, respectively, and the propagation time of the signal from the receiving to the emitting antenna is the same. 6. The multi-frequency positioning system in the shielded space according to claim 2, characterized in that in the SNA signal receiver the frequency range L1 GPS, for example, is replaced by the frequency range L1 Galileo, and the frequency range L5 GPS by the frequency range E5a Galileo. 7. The multi-frequency positioning system in the shielded space according to claim 2, characterized in that the SNA signal receiver is configured to solve a navigation problem in terms of the difference in the propagation time of the SNA signal from radiating antennas located at least at three different points in the shielded space.