Telecommunications device, radiolocation system, and implementation method

Abstract

The invention relates to a telecommunications device (10), comprising a generator (DAC) of one or more signals to be transmitted (Tx); a power amplifier (PA) exhibiting output noise (Npa); a coupler (DC) arranged behind the amplifier (PA); a transmit and receive antenna (AN); a circulator (CC) arranged between the coupler (DC) and the antenna (AN); a first element (ADC A) for measuring a signal (SA), connected to the coupler (DC); a second element (ADC B) for measuring a signal (SB), connected to the circulator (CC); and a computing unit (CU) receiving the signals (SA, SB). Transfer functions (H1; H2) are defined on paths from the output of the amplifier (PA) to the first element (ADC A) or second element (ADC B). The computing unit (CU) is configured to extract the received signal (Rx).

Description

[0001] Telecommunications device, radiolocation system, and implementation method

[0002] [1] Technical field

[0003] [2] The present invention relates to a telecommunications device, of the transceiver type, configured to receive and transmit radio frequency signals. The invention also relates to a radiolocation system comprising such a device. The invention further relates to a method for implementing such a telecommunications device.

[0004] [3] The field of the invention is that of radio frequency communication devices.

[0005] [4] Prior art

[0006] [5] The location of receiving mobile devices in outdoor environments has seen a major technological leap with the deployment of the GPS (Global Positioning System) in the 1980s. However, GPS technology does not work in indoor environments, typically inside buildings, and relatively poorly in urban environments.

[0007] [6] There is therefore a need for radiolocation systems for receiving mobile devices which have both a long range (typically greater than 10 km) and which work well both outdoors and indoors.

[0008] [7] As is known, a location system in an outdoor or indoor environment most often includes, in addition to the mobile device to be positioned, a set of at least three beacons. These beacons are distinguished by the fact that their position is known. Furthermore, they are usually fixed. In such a system configuration, the beacons control the transmissions: a beacon transmits to a mobile device, and the mobile device responds by retransmitting to the beacon. Measuring the transmission time, by taking the difference between the transmission time and the reception time, makes it possible to determine the distance between the beacon and the mobile device. However, such a system requires the receiving mobile device to retransmit signals to the beacons so that a remote server can deduce the mobile device's position, and therefore does not allow the mobile device to perform its own positioning.

[0009] [8] Radiolocation systems also commonly use modulated radio frequency signals, emitted by fixed beacons or antennas, to transmit, for example, positioning data or random data to a receiver. Such random data, for example, data known in advance to the receiver, helps the receiver synchronize with the random data by performing signal correlations. However, such systems require a large frequency transmission bandwidth, typically several tens or hundreds of MHz for radiolocation systems with meter or sub-meter accuracy. Such operation is particularly expensive. Furthermore, such radiolocation systems do not allow for dual operation in either outdoor or indoor environments.

[0010] [9] EP 2822 189 Al, US 2018 / 254787 Al, US 2021 / 258037 Al and US 2023 / 318639 Al describe various examples of telecommunication devices, illustrating the general technological background of the invention.

[0011]

[0010] WO44A219286A1 describes a system and method for radiolocating at least one receiving mobile device, by the mobile device itself, in both outdoor and indoor environments. By overcoming the drawbacks of the prior art, this technology constitutes a particularly advantageous solution, which can be further improved.

[0012]

[0011] In a transceiver, when the received signal (Rx) is frequency-dependently close to the signal to be transmitted (Tx), the reception sensitivity of the received signal (Rx) is degraded due to noise near the power amplifier of the signal to be transmitted (Tx). It is necessary to reduce this noise in order to limit the degradation of sensitivity.

[0013]

[0012] The known solutions for this purpose are:

[0014] a) Classical duplexer: analog filtering allows the noise from the amplifier to be filtered out upstream of the receiving chain. However, this solution does not work when the signals (Tx, Rx) are too close to be filtered.

[0015] b) Reduce the power of the signal to be transmitted (Tx), which reduces noise proportionally. However, this solution has the disadvantage of limiting the transmission power.

[0016] c) Use of cavity filters, which have an excellent quality factor. However, these filters have the disadvantage of being very bulky, especially for low frequencies, and the number of filters must be multiplied if different signals (Tx / Rx) are used simultaneously.

[0017]

[0013] Description of the invention

[0018]

[0014] The object of the present invention is to remedy the above problems.

[0015] To this end, the invention relates to a telecommunications device, comprising: - a signal generator to be transmitted;

[0019] - a power amplifier located downstream of the signal generator to be transmitted and exhibiting noise at the output;

[0020] - a coupler positioned downstream of the power amplifier;

[0021] - a transmitting and receiving antenna;

[0022] - a circulator which is positioned between the coupler and the antenna, and which is configured to receive a signal received from the antenna and transmit the signal to be transmitted to the antenna;

[0023] - a first measuring element for a first signal connected to the coupler; - a second measuring element for a second signal connected to the circulator; and - a computing unit configured to receive the first signal measured by the first element and the second signal measured by the second element; wherein:

[0024] - a first transfer function is defined on a first path going from the output of the power amplifier to the first measuring element of the first signal, passing through the coupler;

[0025] - a second transfer function is defined on a second path going from the output of the power amplifier to the second measuring element of the second signal, passing through the coupler and the circulator;

[0026] the first signal is equal to Npa x H1;

[0027] the second signal is equal to Npa x H2 + Rx; and

[0028] The calculation unit is configured to extract the received signal from the second signal measured by the second element, even if the level of Npa x H2 is higher than the level of the received signal, by applying the formula:

[0029] Rx = SB - SAx H2 / Hl.

[0030]

[0016] Thus, the invention makes it possible to reduce the impact of noise at the output of the power amplifier in order to extract the received signal (Rx). The invention uses simple and inexpensive components, rather than expensive or bulky components such as cavity filters. The invention makes it possible to maintain maximum transmission power of the signal to be transmitted (Tx) and to maintain good sensitivity of the received signal (Rx), even when the received signals (Rx) are very close in frequency to the signals to be transmitted (Tx).

[0031]

[0017] According to other advantageous features of the telecommunications device according to the invention, taken individually or in combination:

[0032] According to one embodiment, the first signal measurement element and the second signal measurement element are two separate analog-to-digital converters.

[0033] In one variant, the first signal measurement element and the second signal measurement element are a single dual analog-to-digital converter. In another embodiment, the processing unit is a microprocessor.

[0034] According to one variant, the computing unit is a programmable logic circuit.

[0035] According to one embodiment, the coupler is a directional coupler.

[0036] According to one variant, the coupler is a resistive coupler.

[0037]

[0018] The invention also relates to a radiolocation system, characterized in that it comprises at least one telecommunication device as described above.

[0038]

[0019] According to a particular embodiment, the radiolocation system comprises:

[0039] at least one mobile receiver to locate;

[0040] at least two fixed transmitting bases, each transmitting base being configured to transmit radio frequency signals, the transmitting bases being synchronized with each other to transmit their respective signals, each transmitting base being configured to transmit a sum of at least two unmodulated pure carrier signals of distinct frequencies, each pure carrier signal being in the form of an unmodulated sustained wave, preferably sinusoidal;

[0041] the receiving mobile being configured to receive and process said radio frequency signals and to deduce its position by calculating the difference(s) in time of flight between the receiving mobile and the transmitting bases, the receiving mobile comprising means for storing position data of the fixed transmitting bases,

[0042] the receiving mobile unit, which also includes:

[0043] Measurement means, for each given signal frequency and for each respective transmitting base, of the phase and amplitude of the signal consisting of the different signals originating from said base and exhibiting said frequency; and computing means connected to the measurement means and storage means, and configured to:

[0044] o apply, for each transmitting base, a high-resolution spectral analysis algorithm on a signal consisting of the different phases and amplitudes measured from the radio frequency signals from said base; o determine, for each transmitting base, from the spectral analysis carried out for said base, a time of flight between the receiving mobile and said base;

[0045] to calculate at least one difference in flight time between the mobile and two transmitting bases, said difference being calculated as the difference between the flight times determined for said bases;

[0046] o determine the position of the receiving mobile, from the calculated time-of-flight difference(s) and the position data of the transmitting bases;

[0047] characterized in that at least one transmitting base includes a telecommunications device as described above.

[0048]

[0020] Preferably, each of the transmitting bases includes a telecommunications device as described above.

[0049]

[0021] The invention also relates to a method for implementing a telecommunications device as described above, characterized in that it comprises the following successive steps:

[0050] the first element measures the first signal equal to Npa x Hl, while the second element measures the second signal equal to Npa x H2 + Rx;

[0051] The processing unit receives the first signal measured by the first element and the second signal measured by the second element; and

[0052] The processing unit extracts the received signal from the second signal measured by the second element, even if the level of Npa x H2 is higher than the level of the received signal, by applying the formula:

[0053] Rx = SB - SAx H2 / Hl.

[0054]

[0022] Description of the figures

[0023] The invention will be better understood upon reading the following description, given solely by way of non-limiting example and made with reference to the accompanying drawings in which:

[0055]

[0024] Figure 1 is a schematic representation of a radiolocation system according to the invention, comprising a receiving mobile and transmitting bases, the radiolocation system integrating a telecommunications device also according to the invention.

[0056]

[0025] Figure 2 is a graph representing two Fourier transforms as a function of time of flight, each Fourier transform corresponding to a distinct transmitting basis and having been applied by the receiving mobile to a signal consisting of the different measured phases of the radio frequency signals from that basis.

[0057]

[0026] Figure 3 is a graph illustrating the impact of noise associated with the signal to be transmitted on listening to the received signal.

[0058]

[0027] Figure 4 is a schematic representation of the telecommunications device and its constituent elements.

[0059]

[0028] Detailed description of the invention

[0060]

[0029] Figure 1 illustrates a radiolocation system (1) according to the invention, configured for positioning at least one receiving mobile device (2) relative to transmitting bases (4). The radiolocation system (1) incorporates at least one telecommunications device (10) also according to the invention, integrated into at least one of the transmitting bases (4). Preferably, each transmitting base (4) incorporates a telecommunications device (10) according to the invention.

[0061]

[0030] The receiving mobile (2) is configured to receive and process radio frequency signals from the transmitting bases (4) and to deduce its position by calculating the time-of-flight difference(s) between the receiving mobile (2) and the transmitting bases (4). The receiving mobile (2) includes means for storing position data from the fixed transmitting bases (4).

[0062]

[0031] Each transmitting base (4) is configured to emit a sum (SIA, S1B) of at least two unmodulated pure carrier signals of distinct frequencies, each pure carrier signal being in the form of an unmodulated continuous wave, preferably sinusoidal.

[0063]

[0032] The receiving mobile (2) further comprises: means for measuring, for each given signal frequency and for each respective transmitting base (4), the phase and amplitude of the signal consisting of the various radio frequency signals originating from said transmitting base (4) and exhibiting said frequency; and

[0064] computing resources connected to measurement and storage resources, and configured for:

[0065] to apply, for each transmitting base (4), a high-resolution spectral analysis algorithm on a signal consisting of the different phases and measured amplitudes of the radio frequency signals from said transmitting base (4);

[0066] to determine, for each transmitting base (4), from the spectral analysis carried out previously, a time of flight between the receiving mobile (2) and said transmitting base (4);

[0067] to calculate at least one difference in time of flight between the receiving mobile (2) and two transmitting bases (4), said difference being calculated as the difference between the times of flight determined for said transmitting bases (4);

[0068] to determine the position of the receiving mobile (2), from the calculated time-of-flight difference(s) and the position data of the transmitting bases (4).

[0069]

[0033] Advantageously, the radiolocation system (1) can be configured as follows:

[0070] - For each transmitting base (4), the frequency difference between the minimum frequency and the maximum frequency of the pure carrier signals emitted by said base (4) is greater than 50 MHz.

[0071] Each pure carrier signal emitted by a transmitting base (4) has a frequency located in the very high frequency band, in other words has a frequency in the range from 30 MHz to 300 MHz.

[0072] - The transmitting bases (4) are configured to transmit the same number of unmodulated pure carrier signals.

[0073] - The transmitting bases (4) are configured so as to transmit their sums (SIA, S1B) of unmodulated pure carrier signals in a frequency-shifted manner, with a predetermined frequency shift between two successive transmitting bases (4).

[0074] - The frequency offset is within the range of 100 Hz to 1 kHz.

[0034] With reference to Figure 1, the following description assumes that the environment in which the receiving mobile (2) operates includes a first obstacle (01) and a second obstacle (02). The two obstacles (01, 02) are buildings, but could alternatively be any other type of structure without affecting the reasoning that follows. For each transmitting base station (4), the radio frequency signals received by the receiving mobile (2) and originating from that base station (4) are divided into two types: the first type consists of SdA and SdB signals arriving along line of sight, and the second type consists of SrA and SrB signals arriving at the receiving mobile (2) following a reflection off an obstacle (01, 02).The signals SdA, SrA, sdB, and srB, respectively, each correspond to the sum S1B of unmodulated pure carrier signals, but they follow different paths. DA and DB, respectively, represent the line-of-sight distance between the receiving mobile (2) and the first transmitting base (4A) and the second transmitting base (4B), respectively, traveled by the signals SdA and SdB. DrA and DrB, respectively, represent the distance traveled by the signals SrA and SrB after bouncing off an obstacle (01) and an obstacle (02), respectively.

[0075]

[0035] For the sake of simplification, only the radio frequency signals originating from the first transmitting base (4A) and bouncing off the obstacle (01) closest to it are considered hereafter. Indeed, the impact of the signals originating from this base (4A) and bouncing off the other obstacle (02) is considered negligible. Similarly, only the radio frequency signals originating from the second transmitting base (4B) and bouncing off the obstacle (02) closest to it are considered hereafter. Indeed, the impact of the signals originating from this base (4B) and bouncing off the other obstacle (01) is considered negligible. Furthermore, for the sake of simplicity, it is assumed that the radio frequency signals bounce only once off one of the obstacles (01, 02).

[0076]

[0036] The positioning of the receiving mobile (2) by the radiolocation system (1) will now be described in detail, with reference in particular to Figure 1.

[0077]

[0037] The method includes an initial step of transmitting position data from the transmitting bases (4) to the storage means of the receiving mobile device (2). The transmission may, for example, consist of each transmitting base (4) transmitting its position coordinates to the receiving mobile device (2), or of pre-programming the position coordinates of the bases within the receiving mobile device (2) during its manufacture or configuration. Following this initial step, the storage means of the receiving mobile device (2) store the position data of the transmitting bases (4).

[0078]

[0038] The method includes a subsequent step in which each transmitting base station (4) emits the sum (SIA, S1B) of unmodulated pure carrier signals of distinct cok frequencies. The phase shift between the signals (SIA, S1B) emitted by the different transmitting bases (4A, 4B) is constant. The sums (SIA, S1B) of pure carrier signals emitted by the bases (4A, 4B) are thus frequency-shifted by a frequency shift Aco. The different cok frequencies used by the bases (4A, 4B), as well as the frequency shift Aco, are known to the receiving mobile device (2), being pre-implemented in or transmitted to it.

[0079]

[0039] In a subsequent step, the receiving mobile (2) receives the radio frequency signals SdA, SdB, SrA, SrB from the transmitting bases (4A, 4B). These signals SdA, SrA, and SdB, respectively, each correspond to the sum S1A and S1B, respectively, of unmodulated pure carrier signals, but they follow different paths. Because the sums S1A and S1B of signals are frequency-shifted by a predetermined frequency shift, known to the receiving mobile (2), the receiving mobile (2) can distinguish the SdA and SrA signals from the first transmitting base (4A) from the SdB and SrB signals from the second transmitting base (4B).

[0080]

[0040] In a subsequent step, the receiving mobile (2) determines, via its measuring means, for each given cok signal frequency and for each transmitting base station (4A, 4B), the phase of the signal consisting of the different signals SdA, SrA; respectively SdB, SrB, originating from that base station (4A, 4B) and exhibiting the cok frequency. Indeed, for example, for the first base station (4A) and for a given cok frequency, the two signals SdA(cok) and SrA(cok) are received by the receiving mobile (2) as a mixture. The phase measured by the receiving mobile (2) for the cok frequency then corresponds to the phase of the signal consisting of the sum of the direct signal SdA and the reflected signal SrA. The same reasoning applies to the signals SdB, SrB originating from the second base station (4B).

[0081]

[0041] In a subsequent step, the receiving mobile (2) applies, via its computing means and for each of the transmitting bases (4A, 4B), a Fourier transform to a signal consisting of the different measured phases and amplitudes of the radio frequency signals received from that base. Indeed, the principle used by the invention is that for a given time delay, the phase shift undergone by a signal with a pure, unmodulated carrier depends on the frequency of that signal. The Fourier transform is typically a discrete Fourier transform, and in particular a discrete Fourier transform with complex coefficients.

[0082]

[0042] Alternatively, it is possible to apply a high-resolution spectral analysis algorithm, without Fourier transform.

[0083]

[0043] For each transmitting base (4A, 4B), the Fourier transform TF applied to the measured phases and amplitudes of the signals from this base is then expressed mathematically via the following function:

[0084] [Math 1] T

[0085]

[0086] F(d n ) =

[0087]

[0044] In this way, by graphically representing, for each transmitting base (4A, 4B), the result of the applied Fourier transform, the computing means can in a subsequent step isolate different peaks corresponding to each signal SdA, SrA or SdB, SrB, and deduce the time of flight of each of these signals.

[0088]

[0045] This is illustrated in the graph in Figure 2, on which two graphical functions 3OA, 30B are represented. These two functions 3OA, 30B correspond respectively to the calculation of the Fourier transform for the first transmitting base (4A) and for the second transmitting base (4B), represented as a function of the time of flight (which is therefore read on the x-axis). During this step, the computing means of the receiving mobile (2) determine the time of flight between the receiving mobile (2) and each of the bases (4A, 4B). To do this, the computing means isolate the peak PlA, PIB having the shortest time of flight. This peak PlA, PIB corresponds to the SdA, SdB signal in line of sight. In the embodiment shown, for the first base (4A), the peak PIA corresponding to the SdA signal has a time of flight TVIA approximately equal to 230 ns. The time of flight TV1 A between the receiving mobile (2) and the first base (4A) is therefore approximately 230 ns.For the second base (4B), the PIB peak corresponding to the SdB signal has a time-of-flight TV1B of approximately 310 ns. The time-of-flight TV1B between the receiving mobile (2) and the second base (4B) is therefore approximately 310 ns. For each of the bases (4A, 4B), the second peak P2A, P2B, which has a lower amplitude than the first peak P2A, P2B and a longer time-of-flight, corresponds to the SrA, SrB signal having bounced off an obstacle (01, 02). This peak P2A, P2B can therefore be advantageously isolated from the first peak P2A, PIB, and not taken into account in the subsequent calculations.

[0046] In a subsequent step, the receiving mobile (2) calculates at least one time-of-flight difference TVdiff between the mobile (2) and two transmitting bases (4A, 4B). The flight time difference TVdiff is calculated as the difference between the flight times TV1A, TV1B determined for the transmitting bases (4A, 4B).In the embodiment shown in Figure 2, the time difference of flight time TVdiff is approximately equal to 80 ns (310 ns - 230 ns).

[0089]

[0047] In the case where the radiolocation system (1) has a number of transmitting bases (4) greater than or equal to three, the receiving mobile (2) calculates several time-of-flight differences between the mobile (2) and transmitting bases (4) taken two by two, each time-of-flight difference being calculated between the mobile (2) and two distinct transmitting bases (4).

[0090]

[0048] In a final step, the computing means of the receiving mobile (2) determine the position of the receiving mobile (2) from the calculated time-of-flight difference(s) TVdiff and the position data of the transmitting bases (4A, 4B), previously stored in the storage means. From the known position data of the transmitting bases (4A, 4B), the absolute position of the receiving mobile (2) is easily given by the classical relationship between wave speed and time-of-flight difference.

[0091]

[0049] In the case where the radiolocation system (1) has a number of transmitting bases (4) greater than or equal to three, the computing means of the receiving mobile (2) cross the different time-of-flight difference measurements in order to determine the position of the receiving mobile (2).

[0092]

[0050] Since the order of magnitude of the time-of-flight difference(s) thus determined is around the nanosecond, it is clear from the foregoing that the radiolocation system (1) advantageously allows for sub-meter accuracy (less than 1 m) for positioning the mobile device (2), even indoors or in urban environments. Furthermore, the receiving mobile device (2) performs its own positioning autonomously. Finally, the radiolocation system (1) has both a long range (typically greater than 10 km), operates equally well in outdoor and indoor environments, and exhibits limited spectral occupancy, increased sensitivity, and a minimal equivalent noise band.

[0051] In this context, we now turn our attention to the telecommunications device (10) integrated into the radiolocation system (1), particularly integrated into the transmitting bases (4).The signals sent by the transmitting bases (4) are received by the receiving mobile (2), but can also be received by the transmitting bases (4) themselves. According to a particular embodiment, the signals sent by the first base (4A) configured as a master device can be received by the second base (4B) configured as a slave device, so that the slave device synchronizes with the master device.

[0093]

[0052] Figure 3 shows a graph illustrating the impact of noise associated with the signal to be transmitted (Tx) on the reception of the received signal (Rx). Frequency is on the x-axis and amplitude is on the y-axis. When the received signal (Rx) is very close in frequency to the signal to be transmitted (Tx) but has a lower amplitude, the received signal (Rx) risks being overwhelmed by noise, caused in particular by the power amplifier. Among other advantages, the invention makes it possible to remedy this problem.

[0094]

[0053] Figure 4 shows the telecommunication device (10) according to the invention and its constituent elements.The device (10) includes a signal generator (DAC) for the signal to be transmitted (Tx); a power amplifier (PA) located downstream of the signal generator (DAC) for the signal to be transmitted (Tx) and having a noise (Npa) output; a coupler (DC) located downstream of the power amplifier (PA) and comprising an input, an output, and a coupled channel; a transmitting and receiving antenna (AN); a circulator (CC) located between the coupler (DC) and the antenna (AN), and configured to receive a received signal (Rx) from the antenna (AN) and transmit the signal to be transmitted (Tx) to the antenna (AN); a first element (ADC A) for measuring a first signal (SA) connected to the coupled channel of the coupler (DC); a second element (ADC B) for measuring a second signal (SB) connected to the circulator (CC); and a computing unit (CU) configured to receive the first signal (SA) measured by the first element (ADC A) and the second signal (SB) measured by the second element (ADC B).

[0095]

[0054] The signal generator (DAC) to be transmitted (Tx) can be any type of radio frequency signal generator, for example, a digital-to-analog converter, an FPGA, a DDS, a PLL, a modulator, etc. The coupler (DC) can be a directional coupler or a resistive coupler. The circulator (CC) can be a single-junction or double-junction circulator. The processing unit (CU) can be a microprocessor or a programmable logic circuit.

[0096]

[0055] The first element (ADC A) for measuring the first signal (SA) and the second element (ADC B) for measuring the second signal (NB) can be two separate analog-to-digital converters. Alternatively, the first element (ADC A) for measuring the first signal (SA) and the second element (ADC B) for measuring the second signal (SB) are a single dual analog-to-digital converter.

[0097]

[0056] For the implementation of the device (10), a first transfer function (H1) is defined on a first path from the output of the power amplifier (PA) to the first element (ADC A) for measuring the first signal (SA), passing through the coupler (DC). Also, a second transfer function (H2) is defined on a second path from the output of the power amplifier (PA) to the second element (ADC B) for measuring the second signal (SB), passing through the coupler (DC) and the circulator (CC).

[0098]

[0057] The first signal (SA) is equal to the noise (Npa) at the output of the power amplifier (PA) multiplied by the first transfer function (Hl).

[0099] [Math 2] SA = Npax Hl

[0100] The second signal (SB) is equal to the noise (Npa) at the output of the power amplifier (PA) multiplied by the second transfer function (H2), plus the received signal (Rx).

[0101] [Math 3] SB = NpaxH2 + Rx

[0102]

[0058] The processing unit (CU) is configured to extract the received signal (Rx) from the second signal (SB) measured by the second element (ABC B), even if the noise level (Npa) multiplied by the second transfer function (H2) is greater than the level of the received signal (Rx), by application of the formula:

[0103] [Math 4] Rx = SB - Npa x H2

[0104] = SB - (SA / Hl) x H2

[0105] = SB - SAx H2 / Hl

[0106]

[0059] Thus, the invention makes it possible to reduce the impact of noise (Npa) at the output of the power amplifier (PA) in order to extract the received signal (Rx).

[0107]

[0060] Furthermore, the system (1) and the device (10) can be configured differently from Figures 1 to 4 without departing from the scope of the invention, which is defined by the claims. In addition, the technical features of the various embodiments and variants mentioned above can be combined, in whole or in part. Thus, the system (1) and the device (10) can be adapted in terms of cost, functionality, and performance.

Claims

Demands 1) Telecommunications device (10), comprising: - a signal generator (DAC) to be transmitted (Tx); - a power amplifier (PA) located downstream of the signal generator (DAC) to be transmitted (Tx) and exhibiting noise (Npa) at the output; - a coupler (DC) located downstream of the power amplifier (PA); - a transmitting and receiving antenna (AN); - a circulator (CC) which is arranged between the coupler (DC) and the antenna (AN), and which is configured to receive a received signal (Rx) from the antenna (AN) and transmit the signal to be transmitted (Tx) to the antenna (AN); - a first element (ADC A) for measuring a first signal (SA) connected to the coupler (DC); - a second element (ADC B) for measuring a second signal (SB) connected to the circulator (CC); and - a computing unit (CU) configured to receive the first signal (SA) measured by the first element (ADC A) and the second signal (SB) measured by the second element (ADC B); in which: - a first transfer function (Hl) is defined on a first path going from the output of the power amplifier (PA) to the first element (ADC A) of measurement of the first signal (SA), passing through the coupler (DC); - a second transfer function (H2) is defined on a second path going from the output of the power amplifier (PA) to the second element (ADC B) of measurement of the second signal (SB), passing through the coupler (DC) and the circulator (CC); the first signal (SA) is equal to Npa x Hl; the second signal (SB) is equal to Npa x H2 + Rx; and The processing unit (CU) is configured to extract the received signal (Rx) from the second signal (SB) measured by the second element (ADC B), even if the level of Npa x H2 is higher than the level of the received signal (Rx), by applying the formula: Rx = SB - SAx H2 / Hl.2) Device (10) according to claim 1, characterized in that the first signal measurement element (ADC A) (SA) and the second signal measurement element (ADC B) (SB) are two separate analog-to-digital converters. 3) Device (10) according to claim 1, characterized in that the first signal measurement element (ADC A) (SA) and the second signal measurement element (ADC B) (SB) are a single dual analog-to-digital converter. 4) Device (10) according to any one of claims 1 to 3, characterized in that the computing unit (CU) is a microprocessor. 5) Device (10) according to any one of claims 1 to 3, characterized in that the computing unit (CU) is a programmable logic circuit. 6) Device (10) according to any one of claims 1 to 5, characterized in that the coupler (DC) is a directional coupler. 7) Device (10) according to any one of claims 1 to 5, characterized in that the coupler (DC) is a resistive coupler. 8) Radiolocation system (1), characterized in that it comprises at least one device (10) according to any one of claims 1 to 7. 9) Radiolocation system (1) according to claim 8, comprising: at least one mobile receiver (2) to be located; at least two fixed transmitting bases (4, 4A, 4B), each transmitting base (4, 4A, 4B) being configured to transmit radio frequency signals (SIA, S1B, SdA, SdB, SrA, SrB), the transmitting bases (4, 4A, 4B) being synchronized with each other to transmit their respective signals, each transmitting base (4, 4A, 4B) being configured to transmit a sum (SIA, S1B) of at least two unmodulated pure carrier signals of distinct frequencies, each pure carrier signal being in the form of an unmodulated continuous wave, preferably sinusoidal; the receiving mobile (2) being configured to receive and process said radio frequency signals (SdA, SdB, SrA, SrB) and to deduce its position by calculating the time-of-flight difference(s) between the receiving mobile (2) and the transmitting bases (4, 4A, 4B), the receiving mobile (2) comprising means for storing position data of the fixed transmitting bases (4, 4A, 4B), the receiving mobile (2) further comprising: means of measuring, for each given signal frequency and for each respective transmitting base (4A, 4B), the phase and amplitude of the signal consisting of the different signals (SdA, SrA; SdB, SrB) originating from said base and exhibiting said frequency; and computing resources connected to measurement and storage resources, and configured for: to apply, for each transmitting base (4A, 4B), a high-resolution spectral analysis algorithm on a signal consisting of the different phases and measured amplitudes of the radio frequency signals from said base (4A, 4B); to determine, for each transmitting base (4A, 4B), from the spectral analysis carried out for said base, a time of flight between the receiving mobile (2) and said base (4A, 4B); to calculate at least one difference in flight time between the mobile (2) and two transmitting bases (4A, 4B), said difference being calculated as the difference between the flight times determined for said bases (4A, 4B); o determine the position of the receiving mobile (2), from the calculated time-of-flight difference(s) and the position data of the transmitting bases (4A, 4B); characterized in that at least one transmitting base (4, 4A, 4B) comprises a telecommunications device (10) according to any one of claims 1 to 7. 10) A method for implementing a telecommunications device (10) according to any one of claims 1 to 7, characterized in that it comprises the following successive steps: The first element (ADC A) measures the first signal (SA) equal to Npa x Hl, while the second element (ADC B) measures the second signal (SB) equal to Npa x H2 + Rx; the processing unit (CU) receives the first signal (SA) measured by the first element (ADC A) and the second signal (SB) measured by the second element (ADC B); and The processing unit (CU) extracts the received signal (Rx) from the second signal (SB) measured by the second element (ADC B), even if the level of Npa x H2 is higher than the level of the received signal (Rx), by applying the formula: Rx = SB - SAx H2 / Hl.

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