Reconstruction de phase

Abstract

A method for controlling an opening (2) of a motor vehicle (1) by detecting the movement of a target, said method comprising the steps of: emitting a radio frequency signal called the emitted signal, intended to be reflected at least partially by said target (5), receiving a radio frequency signal called the return signal, resulting from the reflection of the emitted signal by said target (5), calculating an amplitude A1 and a phase φ1 of said return signal over time, calculating a reconstructed phase φ2 of said return signal, the reconstructed phase φ2 corresponding to the phase φ1 corrected for phase jumps related to the congruent nature of the temporal evolution of the phase φ1, controlling a locking or unlocking of the opening (2), respectively an opening or closing of the opening (2), respectively a tilting from a rest position to a gripping position of a flush handle of the opening (2). Abstract figure: Figure 2

Description

Title of the invention: Phase reconstruction

[0001] The present disclosure relates to a method for controlling an opening of a motor vehicle by detecting a movement of a target, such as a part of a user's body or a transmitter-receiver device. Technical field

[0002] The present disclosure relates to the field of managing access to a motor vehicle. State of the art

[0003] It is known to use radiofrequency signals to control the opening of a motor vehicle opening, for example a trunk door. A radiofrequency signal is an electromagnetic signal comprising a carrier with a frequency of, for example, between 3 kHz and 300 GHz but most often between 5 and 30 GHz in applications in the automotive world.

[0004] There are in particular gesture detection methods used for controlling a vehicle opening. In such a method, a radiofrequency signal is transmitted towards a target and the analysis of a return radiofrequency signal makes it possible to recognize a predetermined gesture made by a user's foot.

[0005] It is also known to use a pulse-type radiofrequency signal (as opposed to a continuous signal) having so-called radiofrequency pulses, i.e. whose carrier frequency belongs to a wide radiofrequency spectrum. The use of this type of signal makes it possible in particular to determine a distance between a target and a device for transmitting and receiving said pulse-type radiofrequency signal.

[0006] The detection of a gesture in the area considered controls the complete opening or closing of the opening.

[0007] It is also known to perform the analysis of radiofrequency signals in this context by calculating a phase of the signals. However, this phase calculation is sometimes difficult to exploit.

[0008] On the one hand, there is significant noise in the phase of the signal over time, for example when the target is stationary.

[0009] On the other hand, the phase of the signal is typically calculated over an angular interval ranging from -180° to +180° (i.e. from -ji to +ir radians) which makes analysis difficult for phase values ​​outside this angular interval.

[0010] An objective of the present invention is to propose a method and a device which overcome these limits. Summary

[0011] A method is proposed for controlling an opening of a motor vehicle by detecting a movement of a target, such as a part of a user's body or a transmitter-receiver device, said method comprising the steps of: a. transmitting, using at least one transmitter, a radiofrequency signal called the transmitted signal, intended to be reflected at least partially on said target, b. receiving, using at least one receiver, a radiofrequency signal called the return signal, originating from the reflection of the transmitted signal on said target, c. from the transmitted signal and the return signal, calculating an amplitude Ai and a phase q>i of said return signal over time, d. calculate a reconstructed phase q>2 of said return signal, the reconstructed phase q>2 corresponding to the phase q>i corrected for phase jumps linked to the congruent nature of the temporal evolution of the phase q>i, e. from the amplitude Ai and the reconstructed phase q>2, control a locking or unlocking of the opening, respectively an opening or closing of the opening, respectively a tilting from a rest position to a gripping position of a handle flush with the opening.

[0012] It is possible to represent a radiofrequency signal S in an orthonormal frame of reference (O, T, q) comprising as origin a point O, as abscissa vector 7 and as ordinate vector q.

[0013] In the orthonormal frame {(). the signal S is a complex number decomposed into the sum of a phase component I (real component along 7) and a phase quadrature component Q (imaginary component along q), so that the signal S is defined by the following equation:

[0014] [Math.l] I + iÇ

[0015] The phase q> of the signal S is equal to its argument:

[0016] [Math.2]

[0017] In the remainder of this document, the half-line corresponding to Q = 0 and I < 0 is called a phase jump line. The phase jump line divides one half of the plane of the reference frame ((A 7. into two quadrants: an upper quadrant and a lower quadrant.

[0018] The in-phase I and quadrature-phase Q components are related to the phase q> and the amplitude A of the signal by the following equations:

[0019] [Math.3] cos(ep) = f / 4

[0020] [Math.4] Oj?) = Ç / 4

[0021] [Math.5] , . ,v

[0022] The amplitude A of the signal S is equal to its modulus in this frame, i.e. the root of the sum of the in-phase component I squared and the quadrature phase component Q squared:

[0023] [Math.6] 4 = vV2 + Q2)

[0024] By congruent character is meant congruence modulo 2ir or circular character.

[0025] Step (e) may be performed as a function of a characteristic relating to the movement of the target.

[0026] Step (e) can further determine at least one characteristic relating to the movement of the target from among a speed of movement, a linear amplitude of movement and / or an angular amplitude of movement, relating to a movement of the target relative to a determined zone of the vehicle, before controlling a locking or unlocking of the opening, respectively an opening or closing of the opening, respectively a tilting from a rest position to a gripping position of a handle flush with the opening.

[0027] The flush handle of the opening may be a deployable or retractable handle, which is flush with an external surface of the opening in a rest position and which can tilt into a gripping position in which access to a cavity is released or a gripping member is deployed.

[0028] The opening can be a motorized opening or a manual opening.

[0029] For example, the opening may be a trunk, a door or a hood of the motor vehicle.

[0030] The transmitter and the receiver may be located in the same transmitting and receiving device. The transmitter and the receiver may be formed by an antenna.

[0031] Multiple transmitters and associated receivers may also be used, the transmitters (and associated receivers) may be located in areas of the vehicle spaced apart from each other.

[0032] The transmitted signal may be a pulse signal comprising a carrier modulated by a sequence of pulses.

[0033] The transmitted signal may be a radiofrequency signal. A radiofrequency signal means a frequency electromagnetic signal whose carrier frequency is between 3 kHz and 300 GHz. The carrier frequency may be between 5 GHz and 30 GHz, for example between 5 GHz and 10 GHz.

[0034] The transmitted signal may be an ultra-wideband signal.

[0035] An ultra-wideband (or UWB) signal is an electromagnetic signal that is characterized by pulses that are very short in time (e.g., of the order of a few nanoseconds) and a very wide bandwidth (e.g., greater than 500 MHz or even more than 1 GHz). The pulses are so short that they have a duration of the order of a few periods of the carrier frequency, which means that the signal can have a considerably wider bandwidth than conventional signals. A UWB signal also has very low transmitted energy. This type of signal is suitable for use in environments with a lot of radio noise or interference.

[0036] Examples of signal processing are described below, making it possible to characterize the movement of the target, in particular when the emitted signal is a pulse signal comprising a carrier modulated by a sequence of pulses. These examples of data processing are given by way of example, and are in no way limiting.

[0037] Step (c) may comprise the sub-steps consisting of:

[0038] (cl) generating a signal I(t) relating to an in-phase component of the return signal, by mixing between the return signal and an in-phase signal and at the frequency of the transmitted signal, and a signal Q(t) relating to a quadrature-phase component of the return signal, by mixing between the return signal and a quadrature-phase signal and at the frequency of the transmitted signal, the signals I(t) and Q(t) defining the two components of a demodulated return signal,

[0039] (c2) obtain sampled data I(t;) and Q(t;) corresponding to a sample time-domain mapping of the signals I(t) and Q(t),

[0040] (c3) extract, in the sampled data I(t;) and Q(f), those relating only to portions of the return signal, for which a time difference between the reception of each portion of the return signal and the emission of a corresponding pulse of the emitted signal, is between or equal to several thresholds,

[0041] (c4) for each sampling instant f, calculate a modulus of the data extracted 1(6) and Q(t;), equal to the amplitude Ai(ti) of the demodulated return signal, and of value equal to the square root of I2(t;)+Q2(ti).

[0042] (c5) search, on the calculated amplitudes Ai(ti), and successively for each

[0043]

[0044]

[0045]

[0046]

[0047]

[0048] pulse of the emitted signal, the presence of a peak of amplitude greater than or equal to a predetermined threshold Aseuib the first detection of such a peak corresponding to the identification of the start of a movement of the target, the instant tj associated with such a peak being recorded and a pulse of index k of the emitted signal being associated with the first detection of such a peak, k being a positive integer, (c6) calculate the phase q>i(k) of the demodulated return signal using the values ​​I and Q associated with said instant tj of the peak, using the following formulas: - if I(tj) >0, then q>i(k) = arctan (Q(tj) / I(tj)); - if I(tj) <0 and if Q(tj) <0, then q>i(k) = arctan (Q(tj) / I(tj)) - + ; and - if I(tj) <0 and if Q(tj) >0, then q>i(k) = arctan (Q(tj) / I(tj)) + ji, (c7) calculate the evolution of the value of the phase q>i, for the following pulses of index k+n of the emitted signal, n being a positive integer. Step (d) may include the substeps of: (dl) calculate the reconstructed phase <p2(k) du signal retour démodulé en utilisant les valeurs I et Q associées auxdits instants tj et tj i du pic et les valeurs de la phase q> i for the impulses of index k and k-1, using the following formulas: - if Q(tj.i) < 0, Q(tj) > 0 and q>i(k) - q>i(k-1) > ji, then<p2(k) = q> i(k) - 2*ji ; - if Q(tj.i) > 0, Q(tj) <0 and q>i(k) - q>i(k-1) < -ji, then<p2(k) = q> i(k) + 2*ji ; and - if not, then <p2(k) = cpi(k). (d2) calculate the evolution of the value of the reconstructed phase q>2, for the following pulses of index k+n of the emitted signal. In other words, the reconstructed phase <p2(k) du signal retour démodulé peut être calculée à l’aide des conditions suivantes : - in the reference frame (q if the displacement of the signal at tj4 to the signal at tj involves a rotation crossing the jump line from the low quadrant to the high quadrant (i.e. a phase jump in the anti-trigonometric direction), the reconstructed phase q>2 is equal to the phase q>i minus 360°; - in the frame (□. 7, if the displacement of the signal at tj4 to the signal at tj involves a rotation crossing the jump line from the high quadrant to the low quadrant (i.e. a phase jump in the trigonometric direction), the reconstructed phase q>2 is equal to the phase q>i plus 360°; - otherwise, the reconstructed phase q>2 is equal to the phase q>i. Rotation means the angular movement in the direction for which the angle formed between the signals at tj4 and tj is the smallest, the angle formed must be minimal. The reconstructed phase q>2 thus calculated allows phase jumps to be taken into account. The reconstructed phase q>2 presents an evolution with a smoothed profile over the pulses of index k (and therefore over time), unlike the phase q>i which presents an evolution with a profile presenting abrupt variations (in “saw teeth”) between two consecutive impulses corresponding to a variation of angle crossing the jump line.

[0049] In other words, the reconstructed phase q>2 makes it possible to overcome the gradients linked to the fact that a complete turn (a rotation of 2ir radians) of the phase has been carried out. Indeed, the phase q>i is calculated with a congruence modulo 2ir radians, it therefore only presents values ​​between -ji and +ir radians (i.e. between -180° and +180°) because of this congruence.

[0050] The phase of the return signal being proportional to the movement of the target, the calculation of the reconstructed phase q>2 allows in particular an easier analysis and more faithful to the movement of the target.

[0051] For example, the sudden variations of the phase q>i do not allow the derivative of the phase q>i to be calculated, unlike the evolution with the smoothed profile of the reconstructed phase q>2 which allows a correct calculation of the derivative of the reconstructed phase q>2, and therefore to deduce the speed and / or acceleration of the movement.

[0052] Furthermore, the reconstructed phase is suitable for long-duration movements, for example movements of a duration greater than the duration for which a phase jump is performed or a time of one cycle between two consecutive phase jumps.

[0053] The predetermined threshold Aseuii of step (c5) can be equal to 20, 50 or 200.

[0054] When the target is stationary, the phase q>i presents a significant noise. Also, it can be planned to select in advance the useful pulses for which the phase is relevant, i.e. the pulses of index k for which there is a movement of the target.

[0055] Since the amplitude Ai does not present any noise when the target is stationary, and presents variations when the target is in motion, it is possible to select the sampling instants tj for which there is a movement of the target, and therefore the pulses of index k associated with these instants tj. These sampling instants tj are then used to calculate the phase q>i.

[0056] In other words, it is possible to eliminate phase noise by selecting the phase values ​​q>i according to a window obtained on the amplitude Ab

[0057] Step (c5) can be performed by a threshold on the amplitude Ab

[0058] In this way, the window is delimited by discriminating the sampling instants f with ij, for which the amplitude is low, or the sampling instants for which there is no or little movement.

[0059] The direction of movement of the opening may depend on the direction of movement of the target, or its trajectory, for example.

[0060] This document also relates to a computer intended to be installed in a motor vehicle comprising at least one processor and at least one memory, said processor having access to the memory to read the steps stored in the memory, said calculator being characterized in that it is configured to implement each of the steps of a method of the aforementioned type.

[0061] This document also relates to a system for managing an opening intended to be installed in a motor vehicle, characterized in that it comprises:

[0062] - at least one antenna intended to emit the transmitted signal and to receive the return signal, And - an electronic management module comprising a computer according to the aforementioned type.

[0063] The management system may be a system for locking or unlocking the opening, a system for opening or closing the opening, and / or a system for tilting from a rest position to a gripping position of a handle flush with the opening.

[0064] This document also relates to a motor vehicle equipped with a movable opening, characterized in that it comprises a system for managing said opening according to the aforementioned type.

[0065] The disclosed features may, optionally, be implemented independently of one another or in combination with one another. Brief description of the drawings

[0066] Other characteristics, details and advantages will appear on reading the detailed description below, and on analyzing the attached drawing showing various figures, in which:

[0067] [Fig-1] is a schematic view of a motor vehicle according to the present document,

[0068] [Fig.2] illustrates the different steps of the method according to the present document,

[0069] [Fig.3] is a graphical representation of a signal in an orthonormal reference frame according to the present document,

[0070] [Fig.4] is a graphical representation of the amplitude Ai over time t according to the present document,

[0071] [Fig.5] is a graphical representation of the phase q>i over time t according to the present document,

[0072] [Fig.6] is a graphical representation of the phase <ps après fenêtrage au cours du temps t selon le présent document,

[0073] [Fig.7] is a graphical representation of a positive phase jump, according to the present document,

[0074] [Fig.8] is a graphical representation of a negative phase jump, according to the present document,

[0075] [Fig.9] is a graphical representation of the evolution of the reconstructed phase q>2 over time t, according to this document. Description of the embodiments

[0076] [Fig.l] schematically represents a motor vehicle 1 comprising a movable opening 2, capable of being controlled by a system for managing said opening 2.

[0077] In the example illustrated, the opening 2 is the rear trunk of the motor vehicle 1.

[0078] Said management system comprises: - at least one antenna 4 intended to transmit and receive a pulsed radiofrequency signal, and - an electronic management module including a calculator. The calculator comprises a processor and at least one memory, and is configured to implement each of the steps of a method for managing the opening of the opening 2 described below.

[0079] The calculator is capable of generating an output signal making it possible to control the opening 2.

[0080] The method for managing the opening of the opening 2 is described below with reference to [Fig.2],

[0081] This method makes it possible to control said opening 2 by detecting a movement of a target 5, such as a part of a user's body or a transmitter-receiver device.

[0082] This method comprises the successive steps described below.

[0083] During a step (a), a signal is emitted, using the antenna, this signal being intended to interact with the target. This signal is an ultra-wideband pulse signal, comprising a carrier modulated by a sequence of pulses, and characterized by pulses that are very short in time (for example of the order of a few nanoseconds) and a very wide bandwidth (for example greater than 500 MHz, or even more than 1 GHz).

[0084] During a step (b), the signal reflected on the target is returned and captured by the antenna, this signal being called the return signal.

[0085] Figure 3 is a representation of any signal S (in vector form $) in an orthonormal frame fa

[0086] The axis along the vector 7 corresponds to the in-phase component I of the signal S and the axis along the vector q corresponds to the in-phase quadrature component Q of the signal S.

[0087] The signal $ is defined by a module (an amplitude) A and an argument (a phase) q>.

[0088] A half-line corresponding to Q = 0 and I < 0 corresponds to a phase jump line 30, this separates a left half 32 of the plane of the reference frame 7, q) into two quadrants: a top quadrant 32a and a bottom quadrant 32b.

[0089] During a step (c) of [Fig.2], an amplitude Al and a phase <pl du signal retour sont calculées au cours du temps.

[0090] Optionally, during a sub-step (cl), we generate: - a signal I(t) relating to an in-phase component of the return signal by in-phase mixing between the return signal and a signal at the frequency of the emitted signal, and - a signal Q(t) relating to a quadrature phase component of the return signal by quadrature phase mixing between the return signal and a signal at the frequency of the transmitted signal. This amounts to carrying out a demodulation of the return signal.

[0091] Then, during a sub-step (c2), sampled data I(t;) and Q(t;) are obtained corresponding to a time sampling of the signals I(t) and Q(t). The sub-step (c22) can be implemented using an analog-digital converter. This time sampling can be implemented downstream of the generation of the signals I(t) and Q(t). The sampling step can be between 0.8 ns and 2 ns, for example equal to 1 ns.

[0092] In a sub-step (c3), in the sampled data I(ti) and Q(ti), those relating only to portions of the return signal are then extracted, for which a time difference between the reception of said portion of the return signal and the emission of a corresponding pulse of the emitted signal is between or equal to several thresholds.

[0093] In this sub-step (c3), it is a matter of extracting, for each pulse of the transmitted signal, data relating to a portion of the corresponding pulse of the transmitted signal, a portion for which the difference between the instant of emission of the pulse of the transmitted signal and the instant of reception of said portion of the corresponding pulse of the return signal is within the thresholds.

[0094] Then, during a sub-step (c4), for each sampling instant h, a modulus of the extracted data I(t;) and Q(L) is calculated, equal to the amplitude Ai(t;) of the demodulated return signal, and of value equal to the square root of I2(ti)+Q2(ti).

[0095] During a sub-step (c5), the presence of an amplitude peak greater than or equal to a predetermined threshold Aseun is searched for on the calculated amplitudes Ai(t;), and successively for each pulse of the emitted signal, such a peak corresponding to the identification of the start of a gesture, the instant tj associated with such a peak being recorded and a pulse of index k of the emitted signal being associated with said peak.

[0096] A time interval 40 corresponding to the sampling instants tj for which Al is greater than Aseuii is then defined.

[0097] We then calculate, during a sub-step (c6) of [Fig.2], the phase q>i(k) of the demodulated return signal using the values ​​I and Q associated with said instant tj of the peak, using the following formulas: - if I(tj) >0, then q>i(k) = arctan (Q(tj) / I(tj)); - if I(tj) <0 and if Q(tj) <0, then q>i(k) = arctan (Q(tj) / I(tj)) - ir; And - if I(tj) <0 and if Q(tj) >0, then q>i(k) = arctan (Q(tj) / I(tj)) + ji.

[0098] The evolution of the value of the phase q>i is then calculated, during a sub-step (c7), for the following pulses of index k+n of the transmitted signal.

[0099] The interest of the time interval of sub-step (c5) is illustrated in figures 4 to 6.

[0100] Figures 4 and 5 are graphical representations of the amplitude Ai and a raw phase q>0 of the return signal over time t.

[0101] The time interval 40 is defined by a lower bound 40a and an upper bound 40b and includes all the sampling instants for which Ai is greater than a value of Aseuiinulle.

[0102] This time interval 40 translates the instants h for which the target is in motion, and contains sampling instants tj.

[0103] We observe in [Fig.5] that the raw phase <poprésente un bruit important en dehors de l’intervalle temporel. Afin de supprimer ce bruit, la phase q> i, illustrated in [Fig.6], is calculated only on the sampling instants tj, i.e. in the time interval 40 (i.e. after the windowing in step (c5)).

[0104] Although the noise has been filtered, the phase q>i remains difficult to exploit, because it presents sudden variations when it reaches ±180°, the calculation of q>i represents a congruence modulo 2+ radians.

[0105] These sudden variations are due to the phase jumps illustrated in Figures 7 and 8.

[0106] [Fig.7] illustrates a first case of phase jump, called positive phase jump.

[0107] We consider a first point M of the signal corresponding to a pulse of index k and a second point N of the signal corresponding to pulse of index k+1.

[0108] In this case, the phase difference between points M and N involves a rotation cop crossing the phase jump line 30 in the trigonometric direction, i.e. from the high quadrant 32a to the low quadrant 32b.

[0109] A rotation is defined in this document as the angular movement in the direction for which the angle formed is minimal.

[0110] This positive phase jump corresponds, in [Fig.6], to a sudden variation of a high peak (a phase q>i approximately equal to +180°, for example a point 60) and to a low peak (a phase q>i approximately equal to -180°, for example a point 62).

[0111] [Fig.8] illustrates a second case of phase jump, called negative phase jump.

[0112] We consider a first point V of the signal corresponding to a pulse of index k and a second point W of the signal corresponding to a pulse of index k+1.

[0113] In this case, the phase difference between points V and W involves a rotation con crossing the phase jump line 30 in the anti-trigonometric direction, i.e. from the low quadrant 32b to the high quadrant 32a.

[0114] This negative phase jump corresponds in [Fig.6] to a sudden variation of a peak low (a phase q>i approximately equal to -180°, for example point 63) to a high peak (a phase approximately q>i equal to +180°, for example point 64.

[0115] In order to take into account these positive and negative phase jumps, during a step (d) of [Fig.2], a reconstructed phase q>2 of said return signal can be calculated, the reconstructed phase q>2 corresponding to the phase q>i corrected for phase jumps linked to the congruent nature of the temporal evolution of the phase q>i.

[0116] During a sub-step (dl), the reconstructed phase is calculated <p2(k) du signal retour démodulé en utilisant les valeurs I et Q associées auxdits instants tj et tj i du pic et les valeurs de la phase pour les impulsions d’indice k et k-1, à l’aide des formules suivantes : - if Q(tj.i) < 0, Q(tj) > 0 and q>i(k) - q>i(k-1) > ji, then<p2(k) = q> i(k) - 2*ji ; - if Q(tj.i) > 0, Q(tj) <0 and q>i(k) - q>i(k-1) < -ji, then<p2(k) = q> i(k) + 2*ji ; and - if not, then<p2(k) = q> i(k).

[0117] Then, during a sub-step (d2), we calculate the evolution of the value of the reconstructed phase q>2, for the following pulses of index k+n of the emitted signal.

[0118] An evolution of the reconstructed phase q>2 over time t is illustrated in [Fig.9].

[0119] Unlike the phase q>i of [Fig.6], the reconstructed phase q>2 presents a smoothed profile: the abrupt variations from a high peak to a low peak, or vice versa (in other words the positive and negative phase jumps), have been removed.

[0120] In this way, the analysis of the characteristics of the target through its reconstructed phase q>2 is facilitated.

[0121] During a step (e) of [Fig.2], from the amplitude Ai and the reconstructed phase q>2, a locking or unlocking of the opening, respectively an opening or closing of the opening, respectively a tilting from a rest position to a gripping position of a handle flush with the opening, is controlled.

Claims

Claims

1. Method for controlling an opening (2) of a motor vehicle (1) by detecting a movement of a target, such as a part of the body of a user or a transmitter-receiver device, said method comprising the steps of: a. transmitting, using at least one transmitter, a radio frequency signal called the transmitted signal, intended to be reflected at least partially on said target (5), b. receiving, using at least one receiver, a radio frequency signal called the return signal, originating from the reflection of the transmitted signal on said target (5), c. from the transmitted signal and the return signal, calculating an amplitude Ai and a phase q>i of said return signal over time, d. calculating a reconstructed phase q>2 of said return signal, the reconstructed phase q>2 corresponding to the phase q>i corrected for phase jumps linked to the congruent nature of the temporal evolution of the phase q>i, e.from the amplitude Ai and the reconstructed phase q>2, control a locking or unlocking of the opening (2), respectively an opening or closing of the opening (2), respectively a tilting from a rest position to a gripping position of a handle flush with the opening (2).

2. Method according to the preceding claim, in which the transmitted signal is a pulse signal comprising a carrier modulated by a sequence of pulses.

3. A method according to the preceding claim, wherein the transmitted signal is an ultra-wideband signal.

4. Method according to one of claims 2 or 3, in which step (c) comprises the sub-steps consisting of: (cl) generating a signal I(t) relating to an in-phase component of the return signal, by mixing between the return signal and a signal in phase and at the frequency of the transmitted signal, and a signal Q(t) relating to a quadrature phase component of the return signal, by mixing between the return signal and a signal in phase quadrature and at the frequency of the transmitted signal, the signals I(t) and Q(t) defining the two components of a demodulated return signal, (c2) obtain sampled data I(t;) and Q(f) corresponding to a time sampling of the signals I(t) and Q(t), (c3) extracting, from the sampled data I(t;) and Q(t;), those relating only to portions of the return signal, for which a time difference between the reception of each portion of the return signal and the emission of a corresponding pulse of the emitted signal, is between or equal to several thresholds, (c4) for each sampling instant h, calculate a modulus of the extracted data I(t;) and Q(t;), equal to the amplitude Ai(t;) of the demodulated return signal, and of value equal to the square root of I2(ti)+Q2(ti). (c5) searching, on the calculated amplitudes Ai(ti), and successively for each pulse of the emitted signal, for the presence of an amplitude peak greater than or equal to a predetermined threshold Aseuii, the first detection of such a peak corresponding to the identification of the start of a movement of the target, the instant tj associated with such a peak being recorded and a pulse of index k of the emitted signal being associated with the first detection of such a peak, k being a positive integer, (c6) calculate the phase q>i(k) of the demodulated return signal using the values ​​I and Q associated with said instant tj of the peak, using the following formulas: - if I(tj) >0, then q>i(k) = arctan (Q(tj) / I(tj)); - if I(tj) <0 and if Q(tj) <0, then q>i(k) = arctan (Q(tj) / I(tj)) - ir; And - if I(tj) <0 and if Q(tj) >0, then q>i(k) = arctan (Q(tj) / I(tj)) + ji, (c7) calculate the evolution of the value of the phase q>i, for the following pulses of index k+n of the emitted signal, n being a positive integer.

5. Control method according to the preceding claim, in which step (d) comprises the sub-steps consisting of: (dl) calculate the reconstructed phase <p2(k) du signal retour démodulé en utilisant les valeurs I et Q associées auxdits instants tj et tj i du pic et les valeurs de la phase q> i for the impulses of index k and k-1, using the following formulas: - if Q(tj.i) < 0, Q(tj) > 0 and q>i(k) - q>i(k-1) > ji, then<p2(k) = q> i (k) - 2*Jt ; - if Q(tj-i) > 0, Q(tj) <0 and cpi(k) - q>i(k-1) < -ji, then<p2(k) = q> i (k) + 2*ji ; and - otherwise, then<p2(k) = cpi(k). (d2) calculer l’évolution de la valeur de la phase reconstruite q> 2, for the following pulses of index k+n of the emitted signal.

6. Control method according to one of claims 4 and 5, in which the predetermined threshold Aseuii of step (c5) is equal to 20, 50 or 200.

7. Control method according to one of claims 4 to 6, in which step (c5) is carried out by a threshold on the amplitude Ab

8. Computer intended to be installed in a motor vehicle (1) comprising at least one processor and at least one memory, said processor having access to the memory to read the steps stored in the memory, said computer being characterized in that it is configured for the implementation of each of the steps of a method according to one of the preceding claims.

9. System for managing an opening (2) intended to be installed in a motor vehicle (1), characterized in that it comprises: - at least one antenna (4) intended to emit the transmitted signal and to receive the return signal, and - an electronic management module comprising a computer according to the preceding claim.

10. Motor vehicle (1) provided with a movable opening (2), characterized in that it comprises a system for managing said opening (2) according to the preceding claim.

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