KR20250038999A - Roll angle estimating apparatus and method - Google Patents

Abstract

The present disclosure relates to a roll angle estimation device and method. Specifically, the roll angle estimation device according to the present disclosure includes a receiving unit that receives an external signal including a satellite signal at predetermined intervals, an anti-jamming unit that performs a beamforming algorithm on the external signal to improve the signal gain of the satellite signal, a correlation unit that extracts a satellite signal using Pseudo-random Noise (PRN) code correlation, and an estimation unit that estimates the roll angle of an antibody based on the extracted satellite signal.

Description

ROLL ANGLE ESTIMATING APPARATUS AND METHOD

The present embodiments relate to a roll angle estimation device and method.

Roll angle provides information about the direction in which the system is moving, which can be used to estimate the attitude, position, and orientation of the system. Roll angle is the angle at which the system rotates around its head, and is the angle between the horizontal and vertical axes.

Roll angles are used in many places. For example, in aircraft, roll angles play an important role in controlling the direction and altitude during flight. By changing the roll angle, the aircraft flies left and right, which can be used to change the direction. Roll angles are also used to estimate the attitude of the aircraft and maintain stability during flight.

In addition, the roll angle of a missile is essential to accurately determine the attitude of the missile and control the flight trajectory. When a missile approaches a target while rotating during flight, the roll angle estimation helps to determine the inclination of the missile and adjust the flight direction to accurately attack the target. The roll angle estimation is also used to compensate for flight errors or shocks that occur during the missile flight. In target attack, the roll angle estimation plays an important role in determining the attack angle of the missile.

As such, roll angle is an important factor used in various fields, but there are cases where devices utilizing roll angle cannot estimate roll angle due to signal interference caused by jamming.

Jamming is a type of interference signal transmitted on a frequency within the radar's reception band to obscure or distort the radar signal. Typically, a noise signal is used. As a type of electronic interference (ECM), when jamming is applied to a device that utilizes roll angle, its original function is not implemented.

Accordingly, research is being conducted to estimate roll angle in a jamming environment.

Against this backdrop, the present disclosure seeks to provide a roll angle estimation device and method for estimating the roll angle of a missile by improving the gain of a satellite signal through a beamforming algorithm.

In order to solve the above-mentioned problem, in one aspect, the present disclosure provides a roll angle estimation device including a receiving unit that receives an external signal including a satellite signal at predetermined intervals, an anti-jamming unit that performs a beamforming algorithm on the external signal to improve the signal gain of the satellite signal, a correlation unit that extracts the satellite signal using Pseudo-random Noise (PRN) code correlation, and an estimation unit that estimates the roll angle of the satellite based on the extracted satellite signal.

In another aspect, the present disclosure provides a roll angle estimation method including a satellite signal receiving step of receiving an external signal including a satellite signal at predetermined intervals, an anti-jamming step of improving a signal gain of the satellite signal by performing a beamforming algorithm on the external signal, a correlation step of extracting a satellite signal using Pseudo-random Noise (PRN) code correlation, and a roll angle estimation step of estimating a roll angle of an antibody based on the extracted satellite signal.

According to the present disclosure, the roll angle estimation device and method can maintain the attitude of an antibody by extracting satellite signals in a jamming environment to estimate a more accurate roll angle.

FIG. 1 is a diagram for explaining a jamming environment according to one embodiment.
FIGS. 2 and 3 are block diagrams illustrating a roll angle estimation device according to one embodiment of the present disclosure.
FIG. 4 is a drawing for explaining calculating the incidence angle of a satellite according to one embodiment.
FIGS. 5 and 6 are diagrams for explaining the results of performing a beamforming algorithm on an external signal according to one embodiment.
FIGS. 7 and 8 are diagrams for explaining increasing the gain of a satellite signal by updating a beam steering vector according to one embodiment.
FIG. 9 is a diagram for explaining the gains of antennas arranged in the first direction and the second direction according to one embodiment.
FIG. 10 is a drawing to more specifically explain a correlation unit according to one embodiment.
FIG. 11 is a flowchart illustrating a roll angle estimation method according to one embodiment of the present disclosure.

Hereinafter, some embodiments of the present disclosure will be described in detail with reference to exemplary drawings. When adding reference numerals to components of each drawing, the same components may have the same numerals as much as possible even if they are shown in different drawings. In addition, when describing the present embodiments, if it is determined that a specific description of a related known configuration or function may obscure the gist of the technical idea of the present invention, the detailed description thereof may be omitted. When "includes," "has," "consists of," etc. are used in this specification, other parts may be added unless "only" is used. When a component is expressed in the singular, it may include a case where it includes plural unless there is a special explicit description.

Additionally, in describing components of the present disclosure, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only intended to distinguish the components from other components, and the nature, order, sequence, or number of the components are not limited by the terms.

In a description of the positional relationship of components, when it is described that two or more components are "connected", "coupled" or "connected", it should be understood that the two or more components may be directly "connected", "coupled" or "connected", but the two or more components and another component may be further "interposed" to be "connected", "coupled" or "connected". Here, the other component may be included in one or more of the two or more components that are "connected", "coupled" or "connected" to each other.

In the description of the temporal flow relationship related to components, operation methods, or manufacturing methods, for example, when the temporal chronological relationship or the chronological flow relationship is described as "after", "following", "next to", or "before", it can also include cases where it is not continuous, as long as "immediately" or "directly" is not used.

Meanwhile, when a numerical value or its corresponding information (e.g., level, etc.) for a component is mentioned, even if there is no separate explicit description, the numerical value or its corresponding information may be interpreted as including an error range that may occur due to various factors (e.g., process factors, internal or external impact, noise, etc.).

Hereinafter, a roll angle estimation device (10) according to one embodiment of the present disclosure will be described with reference to the attached drawings.

FIG. 1 is a diagram for explaining a jamming environment according to one embodiment.

Referring to Fig. 1, an antibody (20) flying through general GNSS satellite (30) navigation transmits and receives data with satellites (30, 30-1, 30-2), calculates the location of the antibody (20), and can fly to a designated location.

However, when the jamming signal generating device outputs a jamming signal around the antibody (20), the area around the antibody (20) changes into a jamming environment.

In the case of an antibody (20) flying with a general GNSS satellite (30) navigation, the gain of the satellite signal received from the satellite (30) is low, making it difficult to estimate the roll angle of the antibody (20) with the signal.

To solve these problems, we propose a roll angle estimation device (10) with an anti-jamming function.

FIG. 2 and FIG. 3 are block diagrams for explaining a roll angle estimation device (10) according to one embodiment of the present disclosure.

Referring to FIG. 2, a roll angle estimation device (10) according to one embodiment of the present disclosure may include a receiving unit (110), an anti-jamming unit (120), a correlation unit (130), an estimation unit (140), and a calculation unit (150).

The roll angle estimation device (10) of the present disclosure receives an external signal including a satellite signal at predetermined intervals, performs a beamforming algorithm on the external signal to improve the signal gain of the satellite signal, and extracts the satellite signal using PRN (Pseudo-random Noise) code correlation, and can estimate the roll angle of the antibody (20) based on the extracted satellite signal.

The roll angle estimation device (10) of the present disclosure is mounted on an antibody (20) and transmits and receives data with surrounding satellites (30) to calculate the position and roll angle of the antibody (20), and can assist in attitude control of the antibody (20) and flight to a target position of the antibody (20).

The receiving unit (110) can receive an external signal including a satellite signal at predetermined intervals. Here, the interval can mean the time from when the external signal is received, to when the roll angle estimation device (10) of the present disclosure estimates the roll angle of the current stock price based on the external signal, and before receiving the external signal again. Accordingly, each roll angle can be calculated at each interval.

To this end, the receiver (110) may include a first array antenna (111), a second array antenna (112), a third array antenna (113), and a fourth array antenna (114). The first to fourth antennas may be arranged on the same plane.

And, the first array antenna (111) and the second array antenna (112) may be arranged to face the first direction, and the third array antenna (113) and the fourth array antenna (114) may be arranged to face the second direction. For example, the first array antenna (111) may be arranged so that the center of the azimuth angle faces the first direction.

Here, the first direction may be the opposite direction to the second direction. For example, in a flying antibody (20), the first direction may be the direction toward the ground, and the second direction may be the direction toward the sky.

Accordingly, the first array antenna (111) and the second array antenna (112) can transmit and receive data with a satellite (30) located at a predetermined azimuth according to the specifications of the array antennas with respect to the first direction.

These first to fourth array antennas (114) may be planar array antennas.

Accordingly, the first to fourth array antennas (114) are arranged in the first and second directions on the surface of the antibody (20) to detect in the ground or ground direction, respectively.

The anti-jamming unit (120) can improve the signal gain of a satellite signal by performing a beamforming algorithm on an external signal.

The correlation unit (130) can extract the satellite signal using PRN (Pseudo-random Noise) code correlation.

The estimation unit (140) can estimate the roll angle of the antibody (20) based on the extracted satellite signal.

In addition, it may further include a calculation unit (150) that receives an estimated roll angle, calculates a beam steering vector based on the roll angle, and updates the beam steering vector calculated in the previous cycle.

That is, when extracting a satellite signal from an external signal, the present disclosure can utilize a beam steering vector of a previous period and estimate a roll angle from the satellite signal to derive a beam steering vector of a current period.

The output unit (150) can select the first direction or the second direction described above based on the estimated roll angle.

Specifically, the calculating unit (150) can determine the antennas from which external signals are received in the next cycle based on the estimated roll angle. For example, the calculating unit (150) can select a first direction, which is a direction in which satellite signals are determined to be received, based on the value of the estimated roll angle. Since the first array antenna (111) and the second array antenna (112) are arranged to face the first direction, when the calculating unit (150) selects the first direction, the receiving unit (110) can receive external signals from the first array antenna (111) and the second array antenna (112).

As described above, the beam steering vector can be derived more quickly by updating the beam steering vector using the estimated roll angle for each cycle.

FIG. 4 is a drawing for explaining calculating the incidence angle of a satellite (30) according to one embodiment.

Referring to FIG. 4, the anti-jamming unit (120) can improve the signal gain of a satellite signal by performing a beamforming algorithm on an external signal.

Specifically, the anti-jamming unit (120) can use an array antenna and a beamforming algorithm to effectively remove jamming signals and increase the signal reception strength of the GNSS.

Modeling of the received signal, i.e., the external signal, from the first array antenna (111) to the fourth array antenna (114) assumes that it is propagated in a straight line from the satellite (30) to the receiver (110) and that the frequency of the wideband jamming is the same as that of the external signal.

Incidence angle of signal input to planar array antenna (Φ: azimuth, θ: elevation) can be expressed in mathematical formula 1 below when converted to a rectangular coordinate system.

[Mathematical Formula 1]

The angle of incidence of the signal input to a planar array antenna consisting of N antennas is When the direction vector of the input signal is can be expressed by the mathematical formula 2 below.

[Mathematical formula 2]

Therefore, the number of satellite (30) signals is M satellite (30) signals. , L jamming signals , thermal noise vector When the input signal is can be expressed by the mathematical formula 3 below.

[Mathematical Formula 3]

In order to obtain the beam steering angle in the present disclosure, the attitude information of the antibody (20) and the incidence angle information of each satellite (30) calculated by performing navigation in the antenna DCM (Direction Cosine Matrix) and anti-jamming unit (120) must be input.

The incidence angle of the satellite (30) is determined through navigation in the anti-jamming unit (120). When obtained, it is converted to the ECEF (Earth Centered Earth Fixed) coordinate system, which can be expressed using the mathematical formula 4 below.

[Mathematical formula 4]

The detailed information rotation vector uses the ENU (East North Up) coordinate system or the NED (North East Down) coordinate system. The Roll component is an increase value in the right screw rotation direction with respect to the right direction of the antibody (20), the Pitch component is an increase value in the right screw rotation direction with respect to the direction of movement of the antibody (20), and the Yaw component is an increase value in the right screw rotation direction with respect to the upper direction of the antibody (20). The coordinate transformation rotation order is composed of Yaw, Pitch, and Roll in that order. And, the Roll component described above can be a roll angle estimated in the previous cycle. If the Euler angle or Quaternion output value is converted to DCM, it can be expressed by the following mathematical expression 5.

[Mathematical Formula 5]

The antenna coordinate system uses the NED (North East Down) coordinate system. The direction from the center of the first array antenna (111) to the center of the second array antenna (112) may represent the x-axis, the right vertical direction in the x direction on the antenna plane may represent the y-axis, and the downward vertical direction in the (x, y) plane may represent the z-axis. In this NED coordinate system, the antenna DCM may be expressed by the following mathematical expression 6.

[Mathematical Formula 6]

The beam steering of the antenna must be done in a straight line from the antenna to the satellite (30). Therefore, the anti-jamming unit (120) uses navigation to determine the incidence angle of the satellite (30). By obtaining the attitude information and converting it into the ECEF coordinate system and multiplying the DCM of the attitude information rotation vector by the DCM of the antenna coordinate system, a beam steering vector in the direction of the satellite (30) can be derived by applying the attitude information to the incident angle of the satellite (30). The beam steering vector can be expressed by the following mathematical expression 7.

[Mathematical formula 7]

Accordingly, the beam steering vector can be obtained as a vector in the direction of each satellite (30) based on the antenna, and can be expressed by the following mathematical expression 8.

[Mathematical formula 8]

As described above, multi-beam steering can be implemented by multiplying the beam steering vectors for the direction of each satellite (30).

Accordingly, since the direction of beam steering is set to face the satellite (30) by using the array antenna and beamforming algorithm, the gain for the satellite signal can be improved by steering the beam in the direction in which the satellite (30) is located.

FIGS. 5 and 6 are diagrams for explaining the results of performing a beamforming algorithm on an external signal according to one embodiment.

Referring to FIG. 5, it can be confirmed that the gain of the satellite signal received from the first array antenna (111) of the receiving unit (110) is low in a jamming environment.

Here, when a beamforming algorithm is performed on a satellite signal, it can be confirmed that the gain of the satellite signal is improved, as shown in Fig. 6.

However, when the antibody (20) rotates, the beam steering direction changes, so it is necessary to derive a beam steering vector that matches the rotation in order to achieve high gain of the satellite signal.

When the antibody (20) rotates at high speed, the method of calculating the steering vector at each moment is inappropriate because it requires a lot of computational time. Therefore, in the present disclosure, the steering vector can be calculated in real time by utilizing the roll angle estimate of the RLL Discriminator.

Again, referring to FIG. 3, the roll angle estimation device (10) of the present disclosure selects an antenna that should receive a current signal using the estimated roll angle and controls the direction of the steering vector directed toward each satellite (30) according to the rotation value.

FIGS. 7 and 8 are diagrams for explaining increasing the gain of a satellite signal by updating a beam steering vector according to one embodiment.

Referring to FIGS. 7 and 8, the roll angle estimated by the estimation unit (140) is transmitted to the calculation unit (150). The calculation unit (150) reads the beam steering vector of the previous period from the steering vector memory, multiplies the attitude information rotation vector according to the roll angle, updates the beam steering vector of the current period corresponding to the rotation angle of the antibody (20), and performs a write operation on the steering vector memory. The steering vector memory may be included in the anti-jamming unit (120) and may be included in the roll angle estimation device (10) as a separate module. Here, the attitude information rotation vector may be expressed by the following mathematical expression 9, and the updated beam steering vector may be confirmed by the above-described mathematical expression 8.

[Mathematical formula 9]

Accordingly, the calculation unit (150) can compensate the beam steering vector of T0 by the roll angle displacement value θ of the rotating body so that the beam steering vector calculated to point toward the satellite (30) at T0 of FIG. 7 also points toward the satellite (30) at T1 of FIG. 8.

FIG. 9 is a diagram for explaining the gains of antennas arranged in the first direction and the second direction according to one embodiment.

As described above, the output unit (150) selects a direction in which to receive an external signal based on the value of the estimated roll angle, and accordingly, the gain of the antenna can be determined.

Referring to FIG. 9, the output unit (150) can select a first direction in which an antenna is placed in which a satellite (30) is included within the detection range in the next cycle, and can perform a beamforming algorithm on external signals received from the first array antenna (111) and the second array antenna (112). Accordingly, an antenna gain as shown in FIG. 9 is generated.

In one embodiment, the output unit (150) can determine a direction in which satellite signals can be received from multiple satellites (30). For example, if one satellite signal can be received in a first direction and two satellite signals can be received in a second direction, the output unit (150) can select the second direction. In addition, the anti-jamming unit (120) can calculate a beam steering vector for each satellite (30) and implement multi-beam steering by multiplying each beam steering vector.

FIG. 10 is a drawing to more specifically explain the correlation unit (130) according to one embodiment.

Referring to FIG. 10, the correlation unit (130) can use PRN code correlation to track a satellite signal from an external signal. Internally, three code signals E (Early), P (Prompt), and L (Late) having different code phases can be generated. Here, E is a signal whose code phase is the earliest, and L is a signal whose code phase is the latest. P is a signal having an intermediate phase between E and L, and can be expressed as G (t+τ) having a code phase error of τ from the pseudo-noise code signal G (t) of the input signal. In order to find out the correlation result, the correlator input signal can first be expressed as in the following mathematical expression 1.

[Mathematical formula 10]

Here, a may represent the satellite signal size, D(t) may represent the satellite (30) orbit information bit, G(t) may represent a pseudo-noise code, ω may represent the carrier frequency component, θ may represent the carrier phase component, and n(t) may represent the white noise component.

One of the signal components passing through the carrier mixer and code mixer can be expressed as in the following mathematical expression 11.

[Mathematical formula 11]

If the result of the above mathematical expression 11 is integrated over the pre-detection integration time (T), i.e., if it passes through a low-pass filter with a bandwidth of 1/T, the result of the following equation can be obtained. In the mathematical expression 12 below, A is the signal magnitude after correlation, R(·) is the code autocorrelation function, τ _k is the code phase error of the received signal and the generated signal, can represent the carrier frequency error, and θ _k can represent the carrier phase error.

[Mathematical formula 12]

Signal acquisition and signal tracking are the acts of collecting the results of the above equations from a digital signal correlator, estimating the components of the carrier signal and the code signal, and updating the state of the digital signal correlator. In other words, signal acquisition means finding the carrier component and the code component where the signal power (P _signal ) shown in the mathematical equation 13 below becomes greater than the noise power (P _noise ), and signal tracking can mean converging the code phase error, carrier frequency error, and carrier phase error components to '0' so that the correlation result maintains the maximum value.

[Mathematical formula 13]

As described above, the correlation unit (130) can receive an external signal, extract a satellite signal from the external signal, and determine whether the sensitivity of the phase signal is below a threshold. For example, the correlation unit (130) can determine whether the sensitivity of the phase signal is below 30 dBHz.

Again, referring to FIG. 3, the correlation unit (130) may include a plurality of correlators having the structure of FIG. 10, transmit each result to the estimation unit (140), and the estimation unit (140) may estimate the roll angle based on each result.

For example, the estimation unit (140) can estimate the roll angle Φ by receiving the result values of S _A , S _R , and S _C from three correlators and using the mathematical expression 14 below, and can configure an RLL (Rotation Locked Loop).

[Mathematical formula 14]

In one embodiment, a computer system (not shown), such as a roll angle estimation device (10), may include at least one of one or more processors, a memory, a storage, a user interface input, and a user interface output, which may communicate with each other via a bus. In addition, the computer system may also include a network interface for connecting to a network. The processor may be a CPU or a semiconductor device that executes processing instructions stored in the memory and/or storage. The memory and storage may include various types of volatile/nonvolatile storage media. For example, the memory may include ROM and RAM.

Below, a roll angle estimation method using a roll angle estimation device (10) capable of performing all of the above-described present disclosures will be described.

FIG. 11 is a flowchart illustrating a roll angle estimation method according to one embodiment of the present disclosure.

Referring to FIG. 11, a roll angle estimation method according to the present disclosure may include a satellite signal receiving step (S1110) of receiving an external signal including a satellite signal at predetermined intervals, an anti-jamming step (S1120) of performing a beamforming algorithm on the external signal to improve the signal gain of the satellite signal, a correlation step (S1130) of extracting a satellite signal using Pseudo-random Noise (PRN) code correlation, and a roll angle estimation step (S1140) of estimating the roll angle of an antibody (20) based on the extracted satellite signal.

The roll angle estimation method may further include a vector calculation step of receiving an estimated roll angle, calculating a beam steering vector based on the roll angle, and updating the beam steering vector calculated in the previous cycle. Here, the beam steering vector may include a direction from the antibody (20) to the satellite (30).

The anti-jamming step (S1120) can perform a beamforming algorithm on an external signal based on the beam steering vector of the previous cycle.

The satellite signal receiving step (S1110) can receive an external signal through at least one of the first array antenna (111), the second array antenna (112), the third array antenna (113), and the fourth array antenna (114) arranged on the same plane.

The first array antenna (111) and the second array antenna (112) may be arranged to face a first direction, and the third array antenna (113) and the fourth array antenna (114) may be arranged to face a second direction. In addition, the first direction may be the opposite direction to the second direction.

Accordingly, the vector calculation step selects the first direction or the second direction based on the estimated roll angle, and the anti-jamming step (S1120) can perform a beamforming algorithm on external signals received from antennas facing the selected direction.

As described above, according to the present disclosure, the roll angle estimation device and method can estimate the roll angle of an antibody by increasing the gain of a satellite signal by utilizing a beamforming algorithm in a jamming environment and extracting the satellite signal with increased gain.

The above description is merely an example of the technical idea of the present disclosure, and those skilled in the art to which the present disclosure pertains may make various modifications and variations without departing from the essential characteristics of the technical idea of the present disclosure. In addition, the present embodiments are not intended to limit the technical idea of the present disclosure but to explain it, and therefore the scope of the technical idea of the present disclosure is not limited by these embodiments. The protection scope of the present disclosure should be interpreted by the claims below, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present disclosure.

Claims (14)

A receiving unit that receives an external signal containing a satellite signal at predetermined intervals;
An anti-jamming unit that performs a beamforming algorithm on the external signal to improve the signal gain of the satellite signal;
A correlation unit for extracting the satellite signal using PRN (Pseudo-random Noise) code correlation; and
A roll angle estimation device including an estimation unit that estimates the roll angle of an antibody based on the extracted satellite signal. In the first paragraph,
A roll angle estimation device further comprising a calculation unit that receives the estimated roll angle, calculates a beam steering vector based on the roll angle, and updates the beam steering vector calculated in the previous cycle. In the second paragraph,
The above anti-jamming unit is,
A roll angle estimation device that performs the beamforming algorithm for the external signal based on the beam steering vector of the previous cycle. In the second paragraph,
The above beam steering vector is,
A roll angle estimation device including a direction toward the satellite from the above antibody. In the second paragraph,
The above receiver
A roll angle estimation device including a first array antenna, a second array antenna, a third array antenna, and a fourth array antenna arranged on the same plane. In paragraph 5,
The first array antenna and the second array antenna,
Positioned so as to face the first direction,
The third array antenna and the fourth array antenna are,
Positioned so as to face the second direction,
The above first direction is,
A roll angle estimation device in the opposite direction to the second direction. In Article 6,
The above output section,
Selecting the first direction or the second direction based on the estimated roll angle,
The above anti-jamming unit is,
A roll angle estimation device that performs the beamforming algorithm on the external signals received from antennas facing a selected direction. A satellite signal receiving step for receiving an external signal containing a satellite signal at predetermined intervals;
An anti-jamming step of improving the signal gain of the satellite signal by performing a beamforming algorithm on the external signal;
A correlation step for extracting the satellite signal using PRN (Pseudo-random Noise) code correlation; and
A roll angle estimation method including a roll angle estimation step of estimating the roll angle of an antibody based on the extracted satellite signal. In Article 8,
A roll angle estimation method further comprising a steering vector calculation step of receiving the estimated roll angle and calculating a beam steering vector based on the roll angle to update the beam steering vector calculated in the previous cycle. In Article 9,
The above anti-jamming step is,
A roll angle estimation method for performing the beamforming algorithm on the external signal based on the beam steering vector of the previous cycle. In Article 9,
The above beam steering vector is,
A roll angle estimation method including the direction toward the satellite from the above antibody. In Article 9,
The above satellite signal reception step
A roll angle estimation method for receiving an external signal through at least one of a first array antenna, a second array antenna, a third array antenna, and a fourth array antenna arranged on the same plane. In Article 12,
The first array antenna and the second array antenna,
Positioned so as to face the first direction,
The third array antenna and the fourth array antenna are,
Positioned so as to face the second direction,
The above first direction is,
A roll angle estimation method in the opposite direction to the second direction above. In Article 13,
In Article 6,
The above steering vector calculation step is,
Selecting the first direction or the second direction based on the estimated roll angle,
The above anti-jamming step is,
A roll angle estimation method for performing the beamforming algorithm on the external signals received from antennas facing a selected direction.

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