Method for geolocating a receiver

Abstract

Method for certifying the geolocation of a receiver. Method for geolocating a receiver (10) by measuring the reception times by the receiver (10) of a plurality of geolocation signals (23) originating from a plurality of transmitters (20), the geolocation signals (23) being emitted on several different wavelengths, at least one geolocation signal having a frequency below 1 GHz. Figure for the abstract: Fig. 1

Description

Description Title of the invention: Method for geolocating a receiver technical field

[0001] The present invention relates to a method for geolocating a receiver.

[0002] — The invention also relates to a receiver, a system, and applications using one of such a process. Previous technique

[0003] It is known to use satellite positioning systems for geolocation a receiver, to know its speed or to broadcast the time by measuring the times of propagation of electromagnetic waves emitted by a set of satellites in constellation. One of the drawbacks of these systems, in addition to their imprecision, is that The various elements, satellites and receiver, need to be in direct line of sight. In urban and wooded environments, building interiors, and basements, This constraint is not respected. Indeed, the calculation of the position relies on a hypothesis of propagation of electromagnetic signals in a direct line between the sa- tellites emitters and receivers, and therefore proves difficult or even impossible when the signals are blocked or significantly attenuated by the receiver's environment. These systems then operate in a degraded mode, or cease to function altogether.

[0004] Furthermore, such systems require the launch and maintenance of numerous sa- Tellites vulnerable to attacks or collisions with satellite debris.

[0005] Moreover, the accuracy of these systems can be affected by the conditions climatic and by ionizing radiation from the sun stopped by the atmosphere.

[0006] Finally, electromagnetic signals from these satellites can be Easily imitated for fraudulent purposes, this threat poses significant challenges. security issues, particularly with regard to applications requiring certification of the recipient's geographical location, such as, for example, se- secure. One way to authenticate a transaction is to use its location and a hour as a means of certification; however, this requires being able to guarantee the integrity of this location.

[0007] — Furthermore, DCF radio-controlled clock systems broadcasting the time via the Large waves exist, such as those emitted in Japan from Mount Otakadoya, Fukushima. in the United Kingdom issuing from Anthorn, Cumbria, in France issuing from d'Allouis and many other countries. However, these systems do not allow for geolocation of the nor to know the precise time, as the receiver's geolocation is not not defined, the time taken for the signal to reach the one not being known.

[0008] A system called BOX NTP BiaTime makes it possible to certify a time but requires a connection to a data network such as the internet. Similarly, the SCP Time system allows for the certification of a time but using bidirectional communication between the time sender and receiver, and therefore bidirectional means of communication, essentially via wired or wireless computer network. More generally, there remains a need to improve geolocation processes and in particular to provide a geolocation process that is effective and accurate everywhere, and especially in dense urban and indoor environments. Description of the invention The invention aims to meet this need, and has as its object, according to a first of its aspects, a method of geolocating a receiver by measuring reception times from a plurality of geolocation signals from a plurality of transmitters, the geolocation signals being emitted on several different wavelengths, at least one geolocation signal being of a frequency below 1GHz. By "geolocation" we mean the position of the receiver, in particular its coordinates in an absolute reference frame or in a local reference frame. The invention offers a simple, inexpensive, and effective solution for certifying the geolocation of the receiver. By using additional certification signals alongside the signals used to calculate the receiver's position, the method reduces or even eliminates sources of error and, in particular, prevents the use of fraudulent geolocation signals, as will be described later. The invention proves useful for applications requiring certification of the receiver's position, particularly in the context of secure transactions, licenses or rights, or in the context of tracking goods or synchronizing computer systems or any kind of clock with the transmitter's clock. Preferably, geolocation signals are emitted at a fixed repetition frequency, and therefore at predictable times according to the transmitters' clocks, and are received offset from one another by known time intervals with an uncertainty that depends, in particular, on the distance the transmitter may be from the receiver, their maximum relative speed, and the maximum differences in signal propagation speed in the media they traverse. All these physical uncertainties allow for the determination of a time between two dates on the receiver's clock for signal reception. Alternatively, the signals may be emitted at predetermined dates or at predetermined but variable transmission frequencies. These date or frequency schedules can advantageously be modified and combined. communicated by any means of communication using messages preferably signed, or alternatively any signal emitted by a transmitter which may include the date of remittance of the next signal or a period of time during which the next signal may be emitted. Preferably, the process includes the reception of additional electromagnetic signals. Preferably, each of the additional electromagnetic signals has a digital signature. A "digital signature" is a mechanism that guarantees the integrity of an electronic message and authenticates its author. This can be achieved, for example, by means of a hash of the message, encrypted with a cryptographic key such as the private key of an asymmetric key pair, or a key shared between the sender and recipient of the message, such as a one-time key. Alternatively, the digital signature can be created by combining the message's hash with a secret number known only to the sender and recipient. The digital signature of a piece of data can be composed of the hash of the data combined with a secret number known during the verification of the signature by a device performing this verification. Qi isati. ificati d'informati In a preferred embodiment, a subset of supplementary electromagnetic signals accompanies the geolocation signals and is referred to as "information signals." The information signal accompanying a geolocation signal includes data relating to the position of the transmitter of said geolocation signal and / or an identifier indicating the position of said transmitter. The information signal preferably includes temporal information enabling the identification of the date and time of transmission of said geolocation signal. The information signal may be received before, after, or simultaneously with the reception of the geolocation signal. In this embodiment, a portion of the additional electromagnetic signals received following the geolocation signals are called "certification signals." Preferably, the method comprises the receiver receiving, within a predetermined time period, a predefined number of certification signals following the geolocation signals used to calculate said geolocation. The information signal may also include meteorological data providing information on the weather, including pressure, cloud cover, temperature, and humidity of an area surrounding the transmitter, and / or velocity data providing information on the propagation speeds of electromagnetic waves in directions and at distances where the geolocation signal is likely to be used. The use of meteorological data can help to account for disturbances that may be experienced by the geolocation signals and / or the certification signals. tracking their route from the transmitter to the receiver. This can, in particular, increase the accuracy of geolocation calculations. The information signal may also include information indicating the time at which the following certification signal(s) must be issued. The certification and information signals can each include a digital signature of the data being transported. In one embodiment, certification signals correspond to information signals. Geolocation signals can be integrated with information signals. Thus, the geolocation signal and the information signal can correspond to a single electromagnetic signal. Geolocation, information and certification signals can be emitted at the same frequency, including a fixed repetition frequency. Information signals may be emitted in contradiction with the frequency at which certification signals are sent. The geolocation signal, the certification signal, and certification signals from the same transmitter can be emitted at different frequencies. Geolocation signals can be emitted on different wavelengths. In particular, these geolocation signals can originate from at least two different transmitters. Preferably, at least one geolocation signal is / are of frequency in the long wave range, in particular with a frequency between 3Khz and 300Khz. At least one geolocation and certification signal can be of frequency between 30 MHz and 3 GHz, corresponding to wavelengths between 10 cm and 10 m. At least one of the geolocation signals and / or at least one of the certification signals can correspond to a GPS (Global Positioning System) signal, specifically of frequency L1 or L2, corresponding to 1575.42 MHz and 1227.60 MHz, respectively. Thus, the geolocation method according to the invention can be implemented using any GPS system. This provides a simple and effective method for certifying the receiver's compatibility with existing GPS systems. Alternatively or additionally, at least one geolocation signal is of frequency belonging to the HF, VHF, UHF, FM or TV bands. The FM band includes electromagnetic signals with a frequency between approximately 88 and 108 MHz. The VHF band includes electromagnetic signals with frequencies between 30 MHz and 300 MHz. The UHF band includes electromagnetic signals with frequencies between between 300 MHz and 3000 MHz. The HF band includes electromagnetic signals with frequencies between 3 MHz and 30 MHz. The TV band includes electromagnetic signals with frequencies between 30 and 3000 MHz. Geolocation and / or certification signals can originate from transmitters located on a satellite, a flying object, or an object floating in the sky. Geolocation signals, for example, can be emitted by satellites in geostationary orbit or moving around the Earth. At least one of the transmitters may be terrestrial, for example, located on a tower. In a preferred embodiment, the geolocation and / or certification signals originate from terrestrial transmitters, particularly transmitters located at altitude or on the tops of buildings such as towers, or even underwater for frequencies below 10 MHz. Such an arrangement increases the accuracy of geolocation and transmission speed measurement. Geolocation signal verification The process may include, for at least one geolocation signal emitted by one transmitter out of a plurality of transmitters, the steps of: Verify the authenticity of the geolocation signal, in particular that of the information signal accompanying the geolocation signal, using a or several control terminals, and If not, trigger a predefined action for fraudulent signaling. in order to perform at least one of the following actions: Prevent the sending of at least one certification signal for certification geolocation calculated using said fraudulent signal, Incorporate the information signal accompanying the signal of geolocation and must be emitted following the geolocation signal fraudulent attribution, or at least one of the certification signals, and preferably the first expected certification signal following the fraudulent geolocation signal for certification purposes, in- formations indicating that the geolocation signal is fraudulent and / or that the accompanying information signal is or are fraudulent, To prevent or cause to be prevented, in particular by jamming, the reception by the receiver, of one of the certification signals, and preferably the first certification signal issued following the geolocation signal fraudulent and expected by the recipient for certification. Verification of certification signals The process may include, for at least one certification signal issued by one issuer out of a plurality of issuers, the steps of: Verify the authenticity of said certification signal, in particular using a or several control points, and in particular his signature and the fact that said A certification signal should not certify a geolocation signal. fraudulent, If not, trigger a predefined action for certification signal incorrect so as to perform at least one of the following actions: Prevent sending, preferably by the sender referenced by the erroneous certification signal from at least one other certification signal fication to be issued following the erroneous certification signal and used for certifying geolocation calculated using the fraudulent geolocation signal or one that can be verified using of the erroneous certification signal, Incorporate at least one of the certification signals in front information to be issued following the erroneous certification signal indicating that said erroneous certification signal cannot be used to certify geolocation, To prevent or cause to be prevented, in particular by jamming, the reception by the receiver of at least one other necessary certification signal to the certification of the geolocation calculated using the signal of fraudulent geolocation or geolocation that can be verified using the Incorrect message. Verification of the authenticity of geolocation data is controlled Control points are receivers of geolocation signals and, preferably, certification signals, communicating with or linked to geolocation or certification signal transmitters and / or jamming stations. Verification of the authenticity of a geolocation signal by each control point can be performed by: Verifying the digital signature contained in the information signal accompanying the geolocation signal, * Calculating an average transmission speed of the geolocation signal between the transmitter and the control terminal, "Comparing said calculated average transmission speed with a range of possible transmission speeds. Information signals can be addressed, in particular, to the terminal(s) of The monitoring system collects data on the transmission speed of electromagnetic waves between the transmitter and the locations where the signal is likely to be used by the receiver, including average minimum and maximum transmission speeds, or meteorological data such as atmospheric pressure, temperature, and humidity in the areas traversed by the geolocation or certification signal. Based on this data, the system then determines the range of possible transmission speeds. Alternatively, the monitoring terminals, or some of them, can collect this data independently, for example, by querying a computer server. If the procedure involves sending information indicating the detection of fraudulent signals to a transmitting station or a jamming station, a process for detecting any malfunction in the sending of such information is preferably put in place, and which may, for example, trigger, after possible verification that a signal which could have been detected as fraudulent has not been detected as valid elsewhere, the procedure provided for in the event of detection of a fraudulent message. Signature verification is done, for example, by calculating the hash of the signal from which the attached signature has been previously removed, by deciphering the attached signature, itself composed of the encrypted hash, and by comparing the calculated hash to the product of the deciphering of the signature. The verification of the authenticity of a geolocation signal or a certification signal by a control terminal that is not fixed can be done by first calculating, using other geolocation signals, a certified position of said mobile terminal, and then, taking into account the uncertainty on its own position, verifying the authenticity of the new geolocation signal or a certification signal. Verified the authenticity of the certificates The control terminals verify the authenticity of a certification signal by Receiving the certification signal within the allotted time, that is to say by example after the supposed date of emission of said signal and before the date assumed where said signal can reach the maximum range to which it can to be used, Verifying the digital signature of said certification signal Receiving the geolocation signal that the said certification signal can certify. Verifying the authenticity of said geolocation signal. Predefined action of the control terminals As described above, when the verification of a geolocation or certification signal is negative, a predefined action for the geolocation signal is triggered. A fraudulent or erroneous certification signal is triggered. As mentioned previously, the predefined action can aim to prevent the sender from transmitting the certification signal following the fraudulent geolocation signal or the erroneous certification signal, or to prevent the receiver from receiving this certification signal. In this case, the predefined action for fraudulent signals can be to jam the certification signal following the fraudulent or erroneous signal expected by the receiver to authenticate the geolocation, for example, using one or more associated or networked jamming stations. Jamming can be restricted to an area defined by: The position of the transmitter of the fraudulent geolocation signal, calculated in particular by triangulation or trilateration using control points as well as by: ii. Let the range be deduced from both the position of the transmitter of the geo- signal. fraudulent calibration, of its power observed upon its reception by the control terminal and the minimum reception power associated with said signal fraudulent geolocation, whether generic, for example associated with the emitter and wavelength, or specific, that is to say inscribed in the information signal accompanying the geolocation signal lisation iii. Let the range of the fraudulent geolocation signal be, starting from its transmitter, as inscribed in the information signal associated with it or associated also with the fraudulent information message. iv. Let the intersection of the two zones defined above in ii) and iii). Jamming can occur over a wider area including the area identified above. A minimum threshold can be predetermined for one of the multiple senders, for a subgroup of these senders, or for one of these senders, below which the receiver cannot use the certification signal to authenticate the geolocation signal. This threshold is advantageously included in the message accompanying the geolocation signal or the certification signal to which it applies. The control system In what follows, "control system" means the set formed by the control terminals and the jamming stations. Preferably, the control system also includes a self-monitoring system whereby any malfunction of the control system gives rise to a predefined self-monitoring action. The malfunction of the control system may, for example, correspond to has: A malfunction in one of the control terminals, A jamming station malfunction, A failure in the communication network used by the control terminals, Detection by a control terminal of the action's malfunction predefined for fraudulent signal triggered by another control terminal, The detection by another control terminal of a fraudulent signal not having no predefined action was taken for fraudulent reporting. In the following, "a faulty control terminal" corresponds to a terminal exhibiting a malfunction as detailed above. Each control point can calculate an area, called a "no-control zone", in which the inaccurate geolocation signal cannot be detected or in which the predefined action, including jamming the fraudulent signal, cannot be carried out. Each control terminal can calculate an area, called a "control zone", in which the fraudulent geolocation or certification signal can be detected and for which the predefined action, including jamming the fraudulent signal, can be carried out. Preferably, the control points, jamming stations, and transmitters are networked; for example, via a 4G, 5G, internet, LoRa, Sigfox, or other communication method. The control points are preferably fixed and time-synchronized. Jamming stations can be combined with the control points and can jam electromagnetic signals emitted by the transmitters, including geolocation and / or certification signals. The preferred predefined self-monitoring action is to attach information about non-control and / or control zones to geolocation signals, specifically by including the coordinates of the zone centers and a parameter indicating their extent, such as the radius, within the accompanying information signal. Alternatively or additionally, the predefined self-monitoring action may consist of attaching information to one or more geolocation signals emitted by a transmitter, specifically within the accompanying information signal, indicating that one or more control points are not connected to that transmitter. In some cases, the predefined self-monitoring action may include, in addition to geolocation signals, information on areas corresponding to overlapping zones of one or more non-monitored areas with monitored areas, particularly in the information signals accompanying the geolocation signals; some monitoring points may be faulty while others are still functioning. valid, a signal located both in a control zone and a non-control zone is considered to be controlled by the receivers and therefore usable for the calculation and certification of a geolocation. When transmitters use varying ranges of wavelengths, only geolocation signals sent with wavelengths in the range of signals detected by the defective control terminal(s) preferentially carry this information. The control terminals can be arranged to calculate the position of a transmitter from the geolocation signals emitted by that transmitter: Compare the calculated transmitter position with a reference position, the reference position corresponding to a position transmitted by said issuer and / or to a pre-recorded position in a database at which the control terminals have access to, Detect a change in the transmitter's position based on this communication. comparison, To transmit, in particular via the sender or by through another issuer, information relating to the position or upon a change in the position of this transmitter relative to the server or said transmitter. Calculation of the position by the receiver Preferably, the calculation of the position is only carried out with geolocation signals whose authenticity, in particular the integrity of the associated data, especially their digital signature, has been verified, as described above. In one embodiment, the receiver has a clock synchronized to the transmitters and calculates its position by: - determining the propagation times of geolocation signals from the transmitters to the receiver, - calculating the distances between the receiver and the transmitters from these propagation times, and - determining the position of the receiver by a localization technique, in particular triangulation and / or trilateration, on the basis of the calculated distances. Alternatively, the receiver lacks a clock synchronized with the transmitters. We will detail below an example of a method that can be used for calculating geolocation when the receiver does not have a clock synchronized with the transmitters. In this embodiment, the receiver is located at point M on a hyperbolic surface of revolution around the axis M1M2, where the transmitters M1 and M2 are the positions of two of the received electromagnetic geolocation signal transmitters. The hyperbola, in a plane containing the axis M1M2, is defined by the position of points M1 and M2, as well as by the difference in distance Ad between each point M1 and M2. point of said hyperbola at the positions of emitters M, and M2, which is calculated by the formula Ad =c,* dt,-c2*dt, — dt*(c,-c2) where dt1 is the difference between the arrival time of the signal from M1 provided by the clock of the receiver, and the sending time of the signal indicated in the information signal attached to said signal, dt2 is likewise, for the signal from the emitter located at M2, dt is the offset between the clock of the receiver and the clock of the emitters and c1 and c2 are the propagation speeds of the signals from emitters M1 and M2 respectively; c1, c2 and dt being known only approximately. However, by using a second, virtual clock internal to the receiver, which provides a time offset from the receiver's actual internal clock at time -dt1, Ad can be recalculated using this new internal clock. With this new clock, the time difference dt'1 between the date the geolocation signal was sent from point M, as recorded in the information signal sent from M, and its arrival time as determined by the new clock is zero. We denote this difference for the clock originating from M as dt', and dt' the difference between the transmitter's clock and the receiver's new clock. Ad == -c2*dt'; +dt**(c;-c2) Now, the speeds c and cz greater than | and close to 1.000293 are known to within 210#, therefore c - c < 4104. and dt' being the time taken by the signal from M to reach the receiver at M, if the authorized or effective range of the signals is less than, for example, 299 km, dt' < 300, 10³ / cc being the speed of light in a vacuum, i.e., 3 * 10⁸ m / s then dt'< | 10- seconds Therefore the uncertainty on Ad =d1-d2 is less than 1 107 # 4 104 # 3 108 =120 m. The receiver is therefore included in a slice delimited by two hyperbolic surfaces of revolution around the line linking M, and Ma, places of emission of the signals, the two hyperbolas being defined by the emitters M, and M and a difference in length from the points of the hyperbolas to the two points M, and M; of c,*dt'; ± 60 m. A shorter signal range reduces this uncertainty accordingly; similarly, the presence in the signal of a minimum average speed and a maximum average speed for reaching any point within its range also reduces the thickness of this slice. Finally, the uncertainty can also be reduced by using another signal from a different transmitter M, received by the receiver, and with a shorter range than the other two transmitters. Slices are thus calculated for various pairs of transmitters, at least three if the altitude is unknown, but preferably from four non-coplanar transmitters; this non-coplanarity characteristic can be deduced from reading the message. accompanying each certification signal, this allows the transmitter of said signal to be located. The fourth non-coplanar transmitter makes it possible to reduce the intersection volume of the different slices or to choose the intersection volume of the slices if this intersection results in two different volumes symmetrical with respect to the plane of the transmitters and no other clue, such as an external indication of the receiver's altitude, can be used to determine in which of the two volumes the receiver is located. Then an intersection of these different slices is calculated; To this end, we can calculate the intersection coordinates of each surface delimiting each slice with two other surfaces delimiting each of another slice, using for example a first orthogonal coordinate system xyz, xy being the pan of the positions of the first 3 emitters and x being an axis linking the positions of two of the 3 emitters. The first hyperbolic surface has the following equation: Xx2 / a? —(y?+2?) / b?=1 We use a parameter t such that t=x / ay / b therefore t* (x / a+y / b)=1+z? / b; therefore x / a+y / b = (1+2° / b? ) / t x / a = V2 [(1+2 / b2) / t + t] y / b = 4 [(1 + 2? / b?) / tt] The second hyperbolic surface is the result of rotating another hyperbolic surface of revolution around the x-axis around an axis parallel to z and perpendicular to the xy plane, and therefore has an equation of the form: ax? + By? + yxy + ez2=1 This equation allows us to find, for each z, one or more values ​​of t: a (a* V2 (t+(1+22 / b2) / t))2? +B*(b 2 (-t+(1+22 / b2) / t))2 +yab*(t2-(1+22 / b2) 2 / t2) / 4 + ez2=1 a (a* V2 (t?+(1+22 / b2))? +B*(b V2 (-12+(1+22 / 62)))? +yab*(t#-(14+22 / b2)) / 4+ ez?t?= t2 a (a* Va (t +(1+27 / 62)42*(1422 / 02)*1) +P*b 72% 14H(1+22 / 07)2-2*(1+22 / 67)*P) +yab*(t#- (1422 / b2)) / 4 + ez? 2=t 1*(aa / 2 + Bb / 2+ yab / 4)412*( 0 a(1+27 / 67)- Bb(14+22 / 02) + ez?-1)+ aa / 2 *(1422 / 6?P + B*b / 2 *(1+22 / 6?}- vab / 4*(1+22 / 62)=0 This is an equation that allows us to give t? as a function of z, and therefore x and y as functions of z. The possibility of finding four different values ​​for a single value of z reflects the symmetry of hyperbolic surfaces with respect to a plane perpendicular to their axis of symmetry, as well as with respect to the plane formed by the positions of the three emitters. Checking each of the solutions, taking into account the sign of the difference d, -d, between the distances to the emitters and the position of the receiver relative to the plane of the emitters, allows us to find the unique intersection of the three surfaces. If no assumption can be made about the position of the receiver relative to the plane of the emitters, then the calculation of the position can be continued for each of the two possibilities and the use of a geolocation signal emitted by a fourth transmitter not coplanar to the first three, in particular after refinement of the calculated position, then makes it possible to determine said relative position of the receiver with respect to the plane formed by the positions of the first three transmitters. The Cartesian equation of the third parabolic surface can therefore generate, for each hypothesis of the receiver's situation relative to the plane formed by the positions of the emitters, an equation in z whose solution(s) can be found by numerical techniques, notably by dichotomy. We can then determine, for each of the two hypotheses of the transmitter's location relative to the plane formed by the positions of the transmitters, the points of intersection of all the surfaces and then verify that the volume in which the receiver is located is within range of the electromagnetic geolocation signals used, and if not, use another combination of transmitters preferably excluding the transmitters calculated to be out of range, and so on until an acceptable combination is found.If the intersection volume is composed of the intersection of more than three layers, it is preferable to first determine the relative position of the receiver with respect to the plane of the three positions of the first three emitters, preferably chosen from triplets of emitters whose emitters are the least aligned. Then, the intersections of the three layers with each of the two surfaces delimiting the fourth layer are determined. These intersections allow the calculation of two reduced volumes relative to the previous volume, and it is determined in which of these two volumes the receiver is located. This process is repeated for all surface intersections to ultimately obtain a minimum intersection volume. Refinement and precision of geolocation. Consulting meteorological data between each of the previously selected transmitters and the volume determined above, or consulting the minimum and maximum average propagation speeds towards this volume for each transmitter, as well as determining the receiver's geolocation more precisely, further reduces the uncertainty in signal propagation speeds and the discrepancy between the receiver's clock and the transmitters' clocks. A precision of 60m on the volume and an uncertainty in signal propagation speed of 2 x 10⁻⁶ instead of 2 x 10⁻⁶ thus reduces the clock uncertainty to 60 / 3 x 10⁸ s + 300 x 10³ / 3 / 10⁸ * 2 x 10⁻⁶ = 2 x 10⁻⁷ + 2 x 10⁻⁶ seconds. This new precision on the clock, as well as the localization of the receiver within a reduced volume, then allows for geolocation calculations to be performed again using the same measurements on the received signals but with more precise signal propagation speeds and a more precise receiver clock. The inaccuracy of the geolocation dt'*(c,-c;) is then 2 107 *3 108 * 2 106 = 12 107 m if cl and c2 are equal to the in- With certainty, or 2 10⁷ * 3 10⁵ * 4 10⁻¹¹ = 24 10⁻¹¹ m if the two propagation speeds are very different, for example if the signal passes through a cyclone. However, the accuracy of the measurement of the signal's arrival time or transmission time can degrade the accuracy of geolocation calculations. Calculating the position of a moving receiver If the receiver is moving, the Doppler effect allows us to calculate the velocity component of the receiver parallel to the line connecting the transmitter, located for example at point M1, and the receiver. This velocity component, combined with the signal propagation speed around the receiver and the time elapsed between receiving the signal from the receiver and receiving the signal from the last receiver used, allows us to calculate the time difference between the time the signal would have been received by the receiver if it were located where it is at the time of receiving the last signal, and the time the signal was emitted. This calculation is performed for each transmitter other than the last one used for geolocation.The calculation described above for a stationary receiver can be used for geolocation calculation; moreover, once the receiver's location is determined, the use of its speed data from geolocation allows its speed to be calculated in the three directions of space. Moving transmitter If a transmitter is moving when the geolocation signal is transmitted, the direction and magnitude of the transmitter's speed are preferably specified in the certification signal accompanying the geolocation signal. After an initial geolocation calculation performed using a first series of geolocation signals, the velocity projection onto each axis linking the receiver to the various transmitters, derived from the Doppler effect, is then adjusted by removing the component of the transmitter's velocity on that axis at the time of transmission, before being used to calculate the receiver's velocity. Receiver in accelerated motion If the receiver is in accelerated motion, it can use the Doppler effect to calculate the projection of its velocity onto the axis connecting it to each transmitter over two successive sets of signals. From this, it can deduce the velocity variation along these axes and thus the receiver's acceleration vector. This calculation is advantageously used to increase the accuracy of the time difference calculation mentioned above, which can be repeated, for example, on the first set of signals, taking into account the previously calculated acceleration to determine even more precise geolocation. The calculation can also be repeated on the second set of signals, allowing for a second, more precise acceleration calculation. This new acceleration enables then possibly recalculate more precise speeds for both sets of signals then a more precise acceleration, and so on until the improvement in accuracy on speeds and accelerations is no longer significant for the user. Receiver clock resynchronization The calculated accuracy advantageously allows the receiver's clock to be resynchronized. A register storing the inaccuracy of this time can be entered, then a calculation, depending in particular on the accuracy of the measuring devices, advantageously allows, at the time of consulting said clock, an updated value of the accuracy of said clock, this time can then be used again for a new geolocation if this accuracy is better than that relating to the times calculated by the methods mentioned above. Location in enclosed spaces If one or both signals travel through a medium other than air or space, or if the signal transmission speed depends on altitude, meteorological data may provide different signal transmission speeds depending on the altitude or depth of the receiver. The receiver can then perform different geolocation calculations by making several assumptions about its altitude or depth. These different assumptions group together different average transmission speed values ​​until the intersections of the calculated segments overlap at a point consistent with the assumption about its depth or altitude.then use the uncertainty in the calculated depth or altitude for the receiver to examine, based on the recorded environment or meteorological data, whether the different average propagation speeds of signals to these different depths or altitudes vary sufficiently within the domain formed by the intersection of the slices to induce a difference in the calculation of said depth or altitude greater than the desired accuracy, and if so, make new assumptions about depth or altitude in this restricted area or simply calculate the geolocation using the data corresponding to the estimated location; then possibly perform a final calculation using the propagation speed values ​​for that location. In enclosed spaces, the average propagation speed can be altered by materials with a refractive index much higher than that of air. Measuring these materials can therefore be difficult, particularly because they are not always visible. One can thus measure the average propagation speeds of waves originating from one or more receivers within a volume and record these measurements, preferably also recording the accuracy of this data, for subsequent use in geo- Precise localization. The recorder's location can be determined using geolocation markers, for example, temporary ones located in the room where the measurements are taken, or using any other localization technique, such as lidar or conventional measuring instruments. The use of lidar also allows for the determination of the volume(s) occupied by air or vacuum, and therefore the extrapolation of transmission velocities within these volumes, particularly if transmission velocity measurements are taken on a surface traversing any concave sub-volume perpendicular to the wave propagation axis. Since the refractive index often varies with temperature, it is preferable to take several measurements, at least two, at times when the temperature of the materials may be different, for example, one in winter and one in summer.These recordings are advantageously disseminated by local transmitters or, alternatively, for example, embedded with the receiver, or accessible via a server. The use of such measurements by a receiver for geolocation can be noted in the certified geolocation record, and the system may advantageously refuse to certify geolocation in an underground location or in a thick-walled building for which such measurements have not been made available to the receiver, or alternatively certify the measurement only with a special note such as 'an unadjusted measurement', such a measurement possibly still allowing the location where the said geolocation was carried out to be found later. A geolocation calculation in a location for which such a record is not available to the receiver can nevertheless use such measured propagation speed data for locations between the transmitter and receiver to adjust the calculation of the average transmission speed of the geolocation signal, for example by making an assumption about the unmeasured part of the space traversed, this assumption being for example that this space is composed of soil, or on the contrary composed of the same materials as those traversed by the wave up to the nearest location to the receiver where the precise measurements were made and use the same average transmission speed. ii Access to average propagation speed data is advantageously obtained by querying a server during which the location, including the uncertainty about it, is advantageously transmitted to said server. The receiver may also possess a map of the terrain, the surface area and height of buildings, the thickness and composition of floors and walls, and possibly the depth of water surfaces and the propagation speeds of waves in this water and soil at the different wavelengths likely to be received by the receiver. The use of such a map can allow to improve positional accuracy by taking into account disturbances and modifications that electromagnetic signals may undergo along their path from transmitter to receiver. The data needed to create such a map can be provided by Lidar scanning the terrain, particularly during construction. The process may include calculating, in addition to the position of the receiver, a temporal information indicating the time at which the geolocation and / or certification signals were received. The process may include calculating, in addition to the receiver's position, the receiver's velocity, the direction of that velocity, and its acceleration vector. Certification Preferably, the method includes certification of the geolocation calculated using geolocation signals. This certification is preferably granted only after the predetermined number of information and certification signals have been received within predetermined timeframes. Before geolocation certification, the process may include at least one of the following actions: The verification of digital signatures of certification signals and information, Verification that none of the certification or information signals includes a message refuting the validity of one of the geolocation signals used for geolocation calculation, Verification that none of the certification signals contain a message invalidating the validity of one of the certification signals used for certification of said geolocation, or Verification based on information and certification signals that said certification signals are certification signals of the signal of geolocation, including verifying the identity or location of the sender said certification signal and the time of its transmission, in particular the date and its time as recorded or referenced in the certification signals fiction and information, Verification that the receiver is located in a controlled area by at least one control point, the information on such areas being provided either by the information signal accompanying the geolocation signal- lisation, either by one of the certification signals, or by a means of communication other communication such as another radio signal or a LoRa or Sigfox network or a means of two-way communication such as a 4G network, Wifi, or a satellite communication connected to transmitters. The process may also include, before certifying the geolocation, verification that at least one certification signal, preferably all certification signals, was received at times compatible with: The time lag between the clocks of the certification signal transmitter and the receiver as determined upon receipt of the geolocation signal having been emitted by this transmitter or during the reception of the certification signal fiction, ii. The distance between the receiver and the transmitter, for example, determined using the geolocation signal emitted by the same transmitter, iii. The time of emission of the geolocation signal, including its date and its time of transmission, as recorded or indicated in the information signal ac- accompanying the geolocation signal or in another certification signal fication, or iv. Meteorological data or known wave propagation speeds by the receiver, this data being transmitted in the certification signal or accessible via a remote server. The receiver, for the purpose of certifying its position, can send a message to one or more control terminals allowing the selection or determination of one or more keys enabling the digital signature of the certification signal(s). The receiver preferably carries an encryption key, private or symmetric, or several single-use keys, allowing it to sign its own geo-location calculations. The receiver software is preferably equipped with a system to check that its own update is not fraudulent, for example by verifying before authorizing said update that the version to be installed has been digitally signed by the publisher of said software or by the operator of the geolocation system. The receiver's position can be certified using an encrypted hash, notably using asymmetric encryption where the private key is stored in the sender's device. Alternatively, a digital signature can be associated with this data, composed of the hash of the data combined with a secret number that is also known during the verification of said signature. The calculated time, speed, or acceleration can also be certified, preferably using an encrypted hash with asymmetric encryption where the private key is stored in the senders. Alternatively, a digital signature can be associated with this data, consisting of the hash of the data mixed with a secret number known at the time of signature verification. A method for obtaining and verifying the digital signature described above is, for example, described in WO2020169542. The receiver's position, the calculated time, the accuracy with which these values ​​were calculated, as well as information relating to the received signals used in their calculation and the meteorological or signal propagation speed data used, along with the uncertainty or accuracy of this data, can be recorded; this information may potentially be used for a subsequent recalculation of the geolocation. The receiver's position, the calculated time and / or speed and other data used in their calculation, as well as their digital signature(s), may be recorded in a storage unit. Alternatively or additionally, this data is transmitted, either in plain text or encrypted, to a remote server for storage. The receiver's position and / or the time and / or the calculated speed are preferably recorded and / or transmitted along with information regarding the accuracy with which this data was calculated. Transmission can be carried out, for example, using a wired or wireless internet network, a 4G or 5G network, or a LoRa or Sigfox network. The receiver can also be configured to certify a position, time, speed or acceleration using a certified position and speed deduced from the received signals and various other instruments including an internal clock, acceleration sensor and / or gyroscope. In one embodiment, certification signals are also used as information and geolocation signals. In this embodiment, the process may include the steps in which: The receiver performs an initial calculation of its position using the signals from geolocation data emitted by the transmitters, The receiver also performs at least a second, and preferably a third calculation of its position using consecutive certification signals to the geolocation signals used for the initial calculation, If at least one of the second and third position calculations fails, the receiver refuses to certify the position calculated using geo- signals location, Otherwise, the receiver compares the first, second, and third calculations. In the event of a significant difference, particularly one showing acceleration or receiver speeds incompatible with nature, particularly non-relativistic, the The receiver refuses to certify the position. In the absence of a significant difference, the receiver certifies the position obtained using geolocation signals. When certification signals are used as geolocation signals Before certifying the geolocation calculated using geolocation signals, the receiver preferably verifies that it can determine the same geolocation at least twice in succession, but preferably three times in succession, using consecutive certification signals emitted by each of the same geolocation signal transmitters. If the receiver takes acceleration into account for these calculations, it can omit this factor for the third geolocation calculation to avoid having to use yet another subsequent signal.The geolocation calculation performed using the first geolocation signals is preferably used to give the spatial and temporal coordinates of the receiver, while the calculation using the following certification signals serves to verify that these certification signals have not been jammed by a control terminal or jamming station, and the calculation using the third certification signals serves to verify that none of these said second certification signals have been jammed as a result of a malfunction of the control system. Receiver The invention also relates, independently or in combination with the foregoing, to a receiver, in particular for the implementation of the certification process as defined above. The receiver can be configured to: To receive electromagnetic signals from a plurality transmitters and used to calculate the geolocation of the receiver, called "geolocation signals", at least one geolocation signal being frequency below 1GHz Determine the geolocation of the receiver by measuring reception time geolocation signals, The receiver can be configured to: To receive additional electromagnetic signals from said emitters, and Determine the authenticity of the geolocation based on the electro- signals additional magnets. Preferably, each additional electromagnetic signal should have a digital signature. Advantageously, the receiver is arranged to be able to decode the digital signatures of additional electromagnetic signals. Additional electromagnetic signals may include signals received as a result of geolocation signals, known as "certification signals". Additional electromagnetic signals may include signals accompanying geolocation signals, known as "information signals". The information signal accompanying a geolocation signal may include data relating to the position of the transmitter of said geolocation signal and / or include an identifier indicating the position of the transmitter, the information signal preferably including temporal information on the date and time of emission of said geolocation signal. The information signal may also include meteorological data, such as pressure, cloud cover, temperature, and humidity, for an area surrounding the transmitter, and / or velocity data, indicating the propagation speeds of electromagnetic waves in directions and at distances where the geolocation signal is likely to be used. The use of meteorological data can account for disturbances that may affect geolocation and / or certification signals on their path from transmitter to receiver. This can, in particular, improve the accuracy of geolocation calculations. The information signal may also include information indicating the time at which the next certification signal should be issued. The certification and information signals can each include a digital signature of the data being transported. The receiver preferably includes: An internal clock A means of communication with a computer network allowing review weather information or information on the speed of propagation of geolocation signals and / or certification signals, A means of communication with a computer network could be that described above, but it can also be a directional network that does not allow that the sending of data, such as a Sigfox or Laura network to transmit the geolocation data, including its position, A means of storing data in environments where the the receiver is likely to be used, including data relating to buildings, for example the thickness of their partitions and walls and / or in the subsoil, including data on soil composition and the depth of rivers, seas, lakes, as well as the salinity of said places This data can influence the signal transmission speed for the places in which said receiver is likely to be used; this a means of data storage that can also be used to record geo- calibrations carried out, particularly during the passage of said receiver, ac- accompanied by time information and speed information and acceleration. Calculation methods for calculating the coordinates and velocities of the transmitter thanks to geolocation and / or certification signals, to data associated with the signals and data available in said receiver. Certification methods to verify digital signatures, create digital signatures and possibly encrypt and sign data. Preferably, the receiver comprises a plurality of receiving antennas, for example three, in particular circular magnetic induction antennas, the antennas preferably being placed in orthogonal planes so as to be able to receive signals from all directions of space. The receiver may include a detection unit configured to detect the time of reception of signals emitted by the transmitters, said unit preferably comprising an integrated circuit or a sub-integrated circuit, the circuit or sub-circuit preferably being configured to operate at a frequency of 60GHz. The receiver can be placed in any environment, particularly in an indoor environment, including inside a building. The receiver can also be configured to receive meteorological data on the weather in an area surrounding the transmitter, and / or velocity data on the propagation speeds of electromagnetic waves in directions and over distances where geolocation signals are likely to be used, including minimum and maximum average signal propagation speeds to reach points within said area surrounding the transmitter. This meteorological and / or velocity data can be included in the information signal accompanying the geolocation signal. Alternatively, the receiver is configured to query a server providing information on meteorological data or speed data, as described above. The receiver can be configured to calculate, in addition to its position, a temporal information indicating the time at which the geolocation and / or certification signals were received. The receiver can be arranged to calculate, in addition to its position, the speed of the receiver and / or transmitters and the direction of said speed. The receiver can be configured to certify its position and / or calculated time, for example using a hash, notably using asymmetric encryption where a private key is stored in the transmitters. The receiver can be configured to record the calculated receiver position and / or calculated time in the storage medium and / or to transmit this data, in clear or encrypted form, to a remote server for storage therein, the receiver position and / or calculated time and / or speed preferably being recorded and / or transmitted with information relating to the accuracy with which this information was calculated. The transmission can be carried out, for example, using a wired or wireless internet network or a 4G or 5G network or a LoRa or Sigfox network or even by satellite transmission, notably desynchronized from the actual location measurement. The receiver can be configured to receive at least one signal with a frequency below 1GHz, preferably in the long wave range, specifically with a frequency between 3Khz and 300Khz. The receiver can be configured to receive geolocation and certification signals with frequencies between 30 MHz and 3 GHz, corresponding to wavelengths between 10 cm and 10 m. The receiver can also be configured to receive GPS (Global Positioning System) signals, including L1 or L2 frequency signals, corresponding to 1575.42 MHz and 1227.60 MHz, respectively. System The invention also relates, independently or in combination with the above, to a system, in particular for the implementation of the certification process as defined above. The system may include: a. A plurality of transmitters, each arranged to emit electromagnetic signals genetics used for geolocation, known as "geolocation signals" and additional electromagnetic signals, b. At least one receiver arranged to receive electromagnetic signals issued by the issuers and configured for: Determine the receiver's position from the geolocation signals, and Determine the authenticity of the geolocation based on the electro- signals additional magnets. The system can be configured to: Calculate, in addition to the receiver's position, temporal information ren- indicating the time at which the geolocation and / or certification signals were received, and / or the speed and / or acceleration of the receiver, and Verify the receiver's position, speed or acceleration and / or time calculated, for example using a hash, notably using asymmetric encryption metric of which a private key is recorded in the issuers. The system may advantageously include at least one control terminal to verify the authenticity and validity of the geolocation signals. The system may include a control system as described previously. Specifically, the control system includes the control terminal(s). The system may include one or more jamming stations. The system can advantageously be arranged to deduce from its clock, synchronized by a certified signal, the position, speed and certified acceleration, as well as possibly from an accelerometer, the time, position, speed and acceleration at a time different from the time of reception of one of the geolocation signals, the calculated data can then be certified by said transmitter, their accuracy being nevertheless adjusted by the accuracy of the clock, and for the calculations of position, speed and acceleration also by the accuracy of the accelerometer. The system is preferably arranged to record, in particular by means of the receiver, the calculated certified position of the receiver and / or the calculated time in a storage unit of the system and / or to transmit this information, in plain text or encrypted, to a remote server for storage therein, the position of the receiver and / or the calculated time and / or speed and acceleration being preferably recorded and / or transmitted with information relating to the accuracy with which this information was calculated as well as with information relating to the received signals which were used in its calculation. Issuers Preferably, transmitters with time-synchronized clocks. Preferably, the transmitter clocks take into account the altitude and speed at which they have traveled or been located since their last synchronization to calculate the time, said calculation taking into account in particular the time flow differentials of clocks according to their altitude, as described by the principle of general relativity. Preferably, at least two transmitters emit geolocation and / or certification signals that overlap in time, with each of the two transmitters emitting geolocation signals at different wavelengths. Preferably, the transmitters are arranged to emit geolocation signals with a predefined offset from a given time zone. At least one transmitter can be arranged to emit a signal in the long wave range, in particular with a frequency between 3kHz and 300kHz. At least one of the transmitters can be arranged to emit a geolocation signal with a frequency below 1GHz. At least one transmitter can be arranged to emit a frequency signal belonging to the HF, VHF, UHF, FM or TV bands. At least one transmitter can be arranged to emit a signal with a frequency between 30 MHz and 3 GHz. At least one transmitter being a GPS (Global Positioning System) transmitter, emitting in particular geolocation signals of frequency LI or L2, corresponding to 1575.42 MHz and 1227.60 MHz, respectively. In one embodiment, at least one of the transmitters is terrestrial, for example, located on a tower, in particular at least one transmitter located at altitude or on the top of buildings such as towers. Such an arrangement increases the accuracy of geolocation and transmission speed measurement. Alternatively or additionally, at least one transmitter is disposed on a satellite, a flying object or an object floating in the sky, said transmitter preferably being arranged to emit a signal of frequency greater than 250 MHz. In particular, the transmitters can be placed in satellites in geostationary orbit or moving around the earth. The fact that transmitters are placed in geostationary orbit improves the accuracy of altitude and transmission speed data, but restricts the wavelengths that can be used to carry the geolocation signals they emit. The transmitter(s) can be configured to transmit the geolocation signal directionally, said transmitter having a directional antenna, for example a dipole antenna and / or at least one director and / or reflector being arranged in the path of the signal emitted by the transmitter so as to direct it in a predefined direction. Each transmitter can be configured to transmit, with the information signal or with at least one certification signal, data relating to the transmitter's range as well as the minimum intensity of its signal when received, the control and non-control zones that are within its range, i.e. within the permit in which it can be received and used. The transmitters can each be arranged to transmit information relating to changes in their own position, speed, and acceleration, in particular on a periodic basis, to the receiver and / or control terminals, or to a server to which the control terminals are connected. Other possible applications Transaction Certification The invention also relates to a method of certifying a transaction or payment, in which the geolocation, or even the time of the transaction, is calculated by implementing the geolocation method according to the invention or using the receiver according to the invention or using the system according to the invention, and optionally the certification of said geolocation and / or the geolocation of the co-signatories is carried out. The process of certifying a transaction or payment described above may also include the steps of: - if the transaction is carried out using two terminals located far apart, display on one or both terminals the location of the other terminal. - to allow and possibly assist signatories in entering their address at the time of signing, as well as the date and time - compare the geolocation, or even the calculated time of the transition or payment, to a position, or even to the transaction or payment time declared by the co-signatories, - In case of discrepancy, the transaction certification is refused. Transaction security The invention also relates to a method for securing a transaction or payment, comprising the steps of: Calculate the geolocation of a receiver associated with a system transaction or payment by implementing the geolocation process lisation according to the invention or using the receiver according to the invention or by using the system according to the invention, In case of calculation failure, or if the geolocation calculation is not sufficiently accurate in relation to predefined geolocation accuracy for said transaction or for said payment, to prevent the transaction or the payment. Preferably, the geolocation calculation is not sufficiently accurate with respect to a predefined geolocation accuracy if the calculation accuracy is greater than the predefined geolocation accuracy, for example Im if the transaction requires only one signatory or 5cm in horizontal coordinates and 50cm in vertical coordinates if it requires several. The invention also relates to a method of controlling a transaction or payment, in which the transition or payment is conditional on the possibility of geolocating the terminal enabling said transaction or payment by implementing the geolocation certification method according to the invention or using the receiver according to the invention or using the system according to the invention. Spatio-temporal usage restriction The invention also relates to a method for restricting a user's use of a license or right, in which: The user's geolocation is then tracked, and the time and / or date is recorded. which the user requests access to, by implementing the geo- calibration according to the invention, using the receiver, or using the system according to the invention, We check if the geolocation belongs to a list of authorized positions. or even if the said time and / or date is within a predetermined time range, And If not, the use of the license or right is prevented. The invention also relates to a method for restricting access to data readable by a device: The geolocation of a receiver associated with the device is calculated. or even the time and / or date when access was requested, by putting in implements the process according to the invention, or by using the receiver or the system according to the invention, We check if the geolocation belongs to a list of authorized positions. even if the time and / or date is within a predetermined time range, and If not, deny access to the data. Route tracking The invention also relates to a method for tracking a journey of goods or a vehicle in which one or more receivers periodically record the certified geolocation, or even the certified time and / or date and / or speed and / or acceleration of the goods or the vehicle by implementing the method, using the receiver or the system according to the invention. Alerts The invention also relates to a position tracking method where an alert signal is triggered when the receiver is detected outside or within a predefined area, or enters or leaves it, the alert being audible, visual, or the subject of a message emitted for example by a LoRa, Sigfox or 4G or 5G network. Clock synchronization, scuba diving, swimming, tunnel drilling and cable and pipeline installation The use of the geolocation method according to the invention, or using the receiver according to the invention, or using the system according to the invention, for: Synchronize remote clocks, Scuba diving as well as swimming, For tunnel boring or the installation of underground cables or pipes without digging trenches, preferably using at least two re- receivers placed at the measurement points, Allowing a user to certify their position, especially if the receiver is equipped with means of capturing secret codes or bio- recognition metric; such a system capable of emitting a readable signature of a few dozens of characters, allowing for the verification of identity, location and the user's time, which can then be verified by a correspondent of said user, who can thus verify this information. To reverse a transaction, including a payment transaction by a means of payment based on the recording of the date and time of said transaction, committed after a cancellation; the cancellation possibly- potentially lead to the cancellation of subsequent transactions. Brief description of the drawings The invention will be better understood upon reading the detailed description that follows, the non-limiting examples of its implementation, and upon examination of the attached drawing, on which: [Fig.1] [Fig.1] schematically and partially represents a system for implementing a geolocation method according to the invention, [Fig.2] [Fig.2] represents an example of a geolocation method according to the invention. [Fig.3] [Fig.3] is a block diagram illustrating different steps of an example process implementing the process of [Fig.2]. [Fig.4] [Fig.4] is a block diagram illustrating different steps of an example process implementing the process of [Fig.2], [Fig. 5] [Fig. 5] is a block diagram illustrating different steps of an example process implementing the process of [Fig. 2], and [Fig.6] [Fig.6] is a block diagram illustrating different steps of an example process implementing the process of [Fig.2]. Detailed description [Fig.1] Figure 1 illustrates an example of system 1 for the implementation of a certification process according to the invention. This system 1 includes a receiver 10. Preferably, the receiver 10 includes a plurality of receiving antennas, for example three, in particular circular magnetic induction antennas, the antennas preferably being placed in orthogonal planes so as to be able to receive signals from all directions of space. In the illustrated example, the receiver 10 further includes a detection unit configured to detect the reception time of signals emitted by the transmitters, said unit preferably comprising an integrated circuit or a sub-integrated circuit, the circuit or sub-circuit preferably being configured to operate at a rate of 60GHz. The receiver 10 can be placed in any environment, in particular in an indoor environment, particularly inside a building. As illustrated in [Fig.1], system 1 also includes a plurality of emitters 20. The transmitters 20 emit electromagnetic signals 23 used to calculate the position of the receiver 10, called "geolocation signals". In addition to the geolocation signals 23, the transmitters 20 each emit additional electromagnetic signals containing data used to calculate the position and to authenticate that position. The additional electromagnetic signals include 25 signals received following the geolocation signals, known as "certification signals". The additional electromagnetic signals include 27 signals accompanying the geolocation signals, known as "information signals". The information signal 27 accompanying a geolocation signal 23 includes data relating to the position of the transmitter of said geolocation signal and / or includes an identifier providing information on the position of the transmitter, the information signal preferably including temporal information on the date and time of emission of said geolocation signal. The information signal 27 also includes meteorological data providing information on the weather, including pressure, cloud cover, temperature, humidity of an area surrounding the transmitter, and / or speed data providing information on the propagation speeds of electromagnetic waves in directions and at distances where the geolocation signal is likely to be used. Alternatively, weather and speed data are accessible from a remote server 40. In the illustrated example, information signal 26 also includes information indicating the time at which the next certification signal must be issued. The certification and information signals each include a digital signature of the data being transported. The transmitters 20 can be terrestrial. For example, they are placed at altitude or on the top of buildings, especially towers, and preferably at different altitudes. Alternatively, the 20 transmitters are placed on satellites in geostationary orbit or moving around the earth. Preferably, these transmitters 20 are suitable for directionally transmitting geolocation signals 23 and certification signals 25. For example, the 20 transmitters each include a directional antenna, for example a dipole antenna. Alternatively, the 20 transmitters each include a director and / or reflector positioned in the path of the signal emitted by the transmitter. so as to direct it in a predefined direction. [Fig.2] In the following, referring to [Fig.2], we will describe a geolocation process according to the invention. Step 101 corresponds to the reception by receiver 10 of geolocation signals 23 emitted by transmitters 20. Prior to, or simultaneously with, or subsequently to step 101, the geolocation signals are analyzed in step 102 to verify their authenticity. For this purpose, system 1 may include a plurality of control terminals 30. The verification of the authenticity of the geolocation signals by each control terminal 30 by verifying the digital signature of the information and certification signals, by calculating an average transmission speed of the geolocation signals between their transmitters and the control terminal, and by comparing said calculated average transmission speed with a range of possible transmission speeds. In the example, the range of possible transmission speeds is determined by taking into account the meteorological situation, including atmospheric pressure, temperature and humidity of the spaces traversed by the signal between its transmitter and the control terminal. If the result of the analysis carried out for a geolocation signal 23 in step 102 is negative, i.e. if the transmission speed of this signal is not within the range of possible values ​​and / or if the integrity of the data of the message attached to the signal is not valid, then a predefined action for fraudulent signal is triggered in step 103 so as to prevent the sender of the fraudulent geolocation signal from sending a certification signal following this fraudulent signal or the receiver from receiving this certification signal. In the illustrated example, the predefined action for fraudulent signal involves jamming, notably through one or more jamming stations associated with the control terminal, the certification signal expected by the receiver 10 for geolocation certification following the reception of the fraudulent geolocation signal. In the illustrated example, the jamming is restricted to a zone Z defined by: i the position of the transmitter 20 of the inaccurate geolocation signal 23, calculated by trilateration using the control terminals, as well as by ii. A geolocation signal strength 23, the identified Z zone cor- corresponding to an area that has been traversed by the geolocation signal inaccurate with a signal strength greater than or equal to a minimum threshold. The minimum threshold can be predetermined for a plurality issuer of transmitters, for a group of these transmitters, or for all of these transmitters, below which the receiver cannot use said certification signal to certify a geolocation. Conversely, if the result of the analysis is positive, the receiver receives at step 104 a first certification signal 25 from each transmitter that emitted the geolocation signals 23. In the same way as for the geolocation signal, the process may include a step 105 in which the authenticity of the certification signal is verified by the control terminals 30. If the result of the analysis performed for certification signal 25 in step 105 is negative, then a predefined action for fraudulent signal in step 106 is triggered to prevent the sender of the fraudulent certification signal from sending a second certification signal following this fraudulent signal or the receiver from receiving this second certification signal. Similar to the geolocation signal, the predefined action is preferably to jam the second fraudulent certification signal. Conversely, if the result is positive, the receiver receives a second certification signal at step 107 from each transmitter that emitted the geolocation signal and the first certification signal. The receiver calculates its position in step 108 using geolocation signals if it has not already been calculated. In the illustrated example, the position of receiver 10 is calculated by trilateration. At this calculation step 108, the receiver can also calculate temporal information indicating the time at which the geolocation and / or certification signals were received. The process also includes in step 108 the calculation, in addition to the position of the receiver, of the speed of the receiver and the direction of said speed. Preferably, the process includes, in step 109, the certification of the receiver's position. For this certification, the receiver calculates its position a second and a third time using the first and second certification signals. The calculation using the first certification signals following the geolocation signals serves to verify that these certification signals have not been jammed by a control terminal or a jamming station controlled by a control terminal. The calculation using the second certification signals makes it possible to verify that the control system did not detect any anomaly in its operation during the possible jamming of the first certification signal. If no problems were detected during these position calculations, then the receiver can certify in step 110 its position calculated in step 108 using the signals from geolocation. Preferably, the certification of the receiver's position can be achieved using an encrypted hash employing asymmetric encryption, the private key of which is stored in the sender 20. Step 110 also includes certification of the calculated receiver time and / or speed; certification is preferably carried out using an encrypted hash with asymmetric encryption, the private key of which is recorded in the transmitters 20. Step 111 involves recording the receiver's position, the calculated time, and information relating to the received signals used in their calculation. The recording is done in a storage unit of the system, specifically the receiver. Alternatively, this information is transmitted to a remote server 40 so that it can be stored there. In the illustrated example, the receiver's position and / or time and / or speed are recorded and / or transmitted with information about the accuracy with which this information was calculated. This information may be recorded and / or transmitted with information relating to the received geolocation signals used in its calculation. [Fig.3] Figure 3 illustrates an example of a method for securing a transaction according to the invention. As illustrated in step 201, the calculation, and even certification, of the position of a receiver associated with a transaction system is carried out by implementing the geolocation process described above. If the calculation of said position or the certification of the position fails, the transaction is prevented at step 202. [Fig.4] Figure 4 illustrates a method for restricting the use of a license or right by a user according to the invention. This process includes, in step 301, determining the user's position, or even the time at which the user requests access, by implementing the geolocation process described above. In step 302, we check if this position belongs to a list of authorized positions, or if said time is within a predetermined time range. If not, the use of the license or right is prevented, which corresponds to step 303. [Fig. 5] Figure 5 illustrates a method for restricting access to readable data. by a device according to the invention. This process involves, in step 401, the geolocation, and optionally the certification of the geolocation, of a receiver associated with the device at the time when access was requested by implementing the geolocation process described previously. In step 402, we check if the geolocation belongs to a list of authorized positions, or even if the time in question is within a predetermined time range, and If not, access to the data is denied at step 403. [Fig.6] Figure 6 illustrates an example of a process for certifying a transaction according to the invention. In step 501, the geolocation of the transaction, or even the time of the transaction, is carried out by implementing the geolocation process according to the invention, and optionally, this geolocation, as well as that of the co-signatories of the transaction, is certified. In step 502, the geolocation, or even the calculated transition time(s), is compared to a geolocation, or even a transition time declared by the co-signatories, and optionally the geolocation of the transition co-signatories is compared to a declared geolocation of the co-signatories. If there is a discrepancy, the transaction certification is refused at step 503. Conversely, the transaction is certified at step 504. Of course, the invention is not limited to the examples described.

Claims

Demands

1. Method for geolocating a receiver (10) by measuring the times of reception by the receiver (10) of a plurality of geolocation signals lisation (23) originating from a plurality of emitters (20), the signals of geolocation (23) being emitted on several different wavelengths different, at least one geolocation signal being of different frequencies less than 1GHz.

2. A method according to the preceding claim, the receiver (10) having a clock synchronized to the transmitters (20), the method comprising the steps consisting of: determine the propagation times of geolocation signals lisation (23) from the transmitters (20) to the receiver (10), Calculate the distances between the receiver (10) and the transmitters. (20) from these propagation times, and to determine the position of the receiver (10) by a technique of localization, particularly triangulation and / or trilateration, based on the calculated distances.

3. Method according to claim |, the receiver (10) being devoid of a clock synchronized to the transmitters (20), the method comprising the steps consisting of: Determine, for several pairs of emitters M1 and M2, a slice delimited by two hyperbolic surfaces of re- evolution around the line linking the emitters M, and M, the two hyperbolas being defined by the position of the emitters M 1 and M; and a difference in length between the points of the hyperbolas to the two positions of the emitters M, and M', Determine the position of the receiver by intersecting the slices.

4. Method according to the preceding claim, the difference in length of the points of the hyperbolas at the two positions of the emitters M, and M'; being calculating in: measuring the reception times of geolocation signals lisation emitted by emitters M1 and M2, respectively, calculating the differences dt, and dt, between the reception times of the geolocation signals and their emission time by the emitters M1 and M2 respectively, calculating the offset dt between the receiver's clock and the transmitter clock, the difference in length being equal to c,* dt,-c2*dt, — dt*(c;-c2), cl and c2 being the velocities of pro- paging of geolocation signals emitted by transmitters M1 and M2, respectively.

5. A method according to any one of the preceding claims, comprising before, after or simultaneously with the reception of geolocation signals (23), reception of signals additional electromagnetic (25; 27) containing data used to calculate and authenticate geolocation.

6. Method according to the preceding claim, a portion of the electrical signals additional tromagnetic signals accompanying geolocation signals lisation, called “information signals” (27), the information signal ac- accompanying a geolocation signal containing data relating to the position of the transmitter of said geolocation signal and / or containing an identifier indicating the sender's location, the information signal preferably containing temporary information porelles on the date and time of emission of said geolocation signal- lisation.

7. A method according to the preceding claim, wherein the signal information (27) also includes meteorological data providing information on the weather, including pressure, cloud cover, temperature, humidity of an area surrounding the emitter, and / or of velocity data providing information on wave propagation speeds electromagnetic fields in directions and at distances where the signal from Geolocation (23) is likely to be used.

8. A method according to any one of claims 5 to 7, a portion of the signals additional electromagnetic (25; 27) being received as a result of the geolocation signals, known as "certification signals" (25), of Preference is given to reception by the receiver within a predetermined timeframe. of at least two consecutive certification signals for each signal of geolocation (23) used for the calculation of said geolocation and issued by the same issuer (20).

9. A method according to any one of the preceding claims, including the calculation, in addition to the position of the receiver (10), of an in- temporal formation indicating the time at which the geo- signals location data has been received.

10. A method according to any one of the preceding claims, including the calculation, in addition to the position of the receiver (10), of the speed of the receiver and the direction of said speed.

11. A method according to any one of the preceding claims, including the step of certifying the position of the receiver (10), particularly using an encrypted hash, notably using encryption asymmetric, in which a private key is stored in the issuers (20).

12. | Method according to any one of claims 10 and 11, wherein The calculated time, speed, or acceleration is certified. preferably being carried out using an encrypted hash, using a asymmetric encryption where a private key is stored in the emitters (20).

13. A method according to any one of the preceding claims, wherein one- record of information relating to the signals received which were used for their calculation and / or details of the geolocation calculations performed, particularly regarding time, position and speed.

14. A method according to any one of the preceding claims, in which the receiver (10) possesses a map of the relief, the surface and the height of buildings, and thickness and spacing of floors and walls as well as their composition, and / or the depth of the surfaces in water as well as wave propagation speeds in these waters, and / or in the soil at the different wavelengths that can be received by said receiver.

15. A method according to any one of the preceding claims, in which of the geolocation signals (23) originating from at least two emitters overlap in time, these geolocation signals- lisation (23) being of different wavelengths.

16. A method according to any one of the preceding claims, the geolocation signals (23) being emitted over several lengths of different wavelengths.

17. A method according to any one of the preceding claims, at least one of the transmitters being terrestrial, in particular located on a tower.

18. | Method according to any one of the preceding claims, the geolocation signals (23) from transmitters having Clocks synchronized in time.

19. Method according to the preceding claim, the clocks of the transmitters taking into account the altitude and speed at which they traveled or have been located since their last synchronization to calculate the time, the said calculation taking into account in particular the differences of clock time flow according to their altitude, as described by the principle of general relativity.

20. | Receiver (10), in particular for the implementation of the geo- calibration according to any one of the preceding claims, configured for: receive geolocation signals (23) from a plurality of emitters, at least two emitters transmitting at different wavelengths, at least one geolocation signal since the frequency of the lisation is less than 1GHz, Determine the geolocation of receiver (10) by measuring geolocation signal reception time.

21. Receiver according to the preceding claim, comprising a unit of detection configured to detect the moment signals are received emitted by the transmitters, said unit preferably comprising a circuit integrated or a sub-integrated circuit, the circuit or sub-circuit being preference configured to operate at a frequency of 60 GHz.

22. | Receiver according to any one of claims 20 and 21, being placed in an indoor environment, particularly inside a building.

23. System for implementing the process according to any one of the claims 1 to 19, comprising a plurality of emitters (20), each arranged to emit geolocation signals, at least one of the transmitters emitting electromagnetic signals over wavelengths of different waves from one of the other transmitters, at least one Since the geolocation signal has a frequency below 1GHz, At least one receiver (10) arranged to receive the signals electromagnetic fields emitted by the transmitters and configured for: Determine the position of receiver (10) from the signals geolocation.

24. System according to the preceding claim, with at least two emitters each emitting geolocation signals at different wavelengths of different wavelengths.

25. Method for certifying a transaction or payment, in which : The geolocation of the transaction is calculated or of the payment, or even the time of the transaction or the payment by implementing the geolocation process according to any one of claims 1 to 19 or using the receiver according to any one of claims 20 to 22 or using the system according to any of the claims instructions 23 to 24, and optionally the certification is carried out geolocation and / or geolocation of co-signatories of the transaction or payment.

26. | A method for securing a transaction or payment, comprising the steps involved in: If the transaction is carried out using two terminals distant from each other, display on one of the terminals or on the two terminals, the location of the other terminal, Calculate the geolocation of an associated receiver to a transaction or payment system by putting in implements the geolocation process according to any of claims 1 to 19 or using the receiver according to one any of claims 20 to 22 or using the system according to any one of claims 23 to 24, In case of calculation failure, or if the geolocation calculation The definition is not sufficiently precise with regard to a predefined geolocation accuracy for said transaction or for said payment, prevent the transaction or the payment.

27. ​​Method of restricting the use of a license or right by a user, in which: The user's geolocation is calculated. or even the time and / or date that the user requests access, by implementing the geolocation process according to any one of claims 1 to 19 or using the receiver according to any one of claims 20 to 22 or using the system according to any of the claims instructions 23 to 24, We check if the geolocation belongs to a list of authorized positions and / or if said date and / or time is in a predetermined time slot, and If not, prevent the use of the license or the right.

28. Method for restricting access to device-readable data: The geolocation of a receiver is calculated. associated with the device, or even the time and / or date at which Access was requested, implementing the geo- calibration according to any one of claims 1 to 19 or using the receiver according to any one of the claims instructions 20 to 22 or using the system according to one any of claims 23 to 24, We check if the geolocation belongs to a list of authorized positions, or even if said time and / or date is in a predetermined time slot, and If not, deny access to the data.

29. A method for tracking the journey of goods or a vehicle in which one or more receptors periodically record the geolocation lisation, or even the certified time and / or date or the speed of the mar- goods or the vehicle by implementing the geolocation process lisation according to any one of claims 1 to 19 or using the receiver according to any one of claims 20 to 22 or using the system according to any one of claims 23 to 24, the position of the receiver(s) and / or the time and / or date at which this The position was calculated, preferably certified, by implementing the method according to claim 11.