WO2016095064A1 - Aperture antenna array, method and system for locating, tracking, detecting and controlling the access of people and objects - Google Patents

Abstract

The invention relates to an aperture antenna array, and to a method and a system for determining the location, the tracking, the detection and the control of the access of people and objects, with a determined attribute, in a determined topological space and at a determined time, by means of an aperture antenna array that measures the angles of arrival and departure of radiofrequency transmissions. The antenna array is circular, flat and sectorial and forms part of a marker radio beacon which also comprises a transceiver, an omnidirectional antenna, a microcontroller, a battery and the circuitry. The antennae are arranged in a radial form on a circle pertaining to a plane of symmetry and cover 360° in the preferred embodiment, with the apertures facing outside the circle and the related waveguides and throats thereof towards the inside. There is a tube in the centre of the array, the longitudinal axis of said tube being perpendicular to the plane, where the intersection of the two corresponds to the centre of the array.

Description

 GROUPING OF OPENING ANTENNAS, METHOD AND SYSTEM FOR LOCATION, MONITORING, DETECTION AND ACCESS CONTROL OF PERSONS OR OBJECTS.

TECHNICAL SECTOR

 This invention is related to wireless communications, with antennas and especially with the opening antenna groupings and with the triangulation technique. In its application it is related to the location, tracking, detection and access control systems of people and mobile objects. International Classification G08B 1/08, G08B 5/22, H01Q 3/00 and H01Q 3/02.

 DESCRIPTION OF PRIOR ART

 The location and tracking of people and moving objects outdoors, through global positioning systems is optimal, however it has technical restrictions for use in cities with high buildings, as well as in interior spaces, since the signals are attenuated GPS satellites, so the use of alternative techniques that solve this lack have been investigated a lot.

 Notwithstanding the foregoing, there is no technology that meets the following characteristics:

 Possibility of using it without requiring the support of others,

 Have low installation and maintenance cost,

 Operate efficiently in different environmental conditions,

 Position accuracy; by way of example less than 1 meter.

Most of the technologies used in location systems are based on the use of electromagnetic waves (E.), especially radio frequencies (R.F.) and in some cases ultrasound waves (U.S.).

 This presentation discloses an array of opening antennas, a method and a system that aim to correct the aforementioned limitations and makes a review of the previous technologies as well as the theoretical principles and fundamentals that support it.

 The doctoral thesis "Indoor Positioning Technologies" by R. Mautz, 2012, contains a review of the thirteen most used technologies to date, describing and analyzing the concepts related to them. It also determines and compares the measurement parameters in these technologies.

 On the other hand, in the PhD dissertation "Active Microwave Tagging Systems by M. Kossel, 2000, a detailed explanation is made of the different RFID and identification systems using TAGS. Within the applications that these systems have, which use transmitters and receivers of RF, is the identification of people and moving objects

In US Patent No. 6,421,000 Bl a method and an apparatus with an array of antennas are described to mitigate multipath distortions, since it is the most limiting factor for the use of RF waves in location systems. Antenna pooling is used to discriminate between a desired RF signal and the remaining components of the multipath, based on the arrival angles. In the publication "Determining RF Angle of Arrival Using COTS Antenna Arrays; A Field Evaluation" by the authors Hsieh-Chung Chen et al (2012), it is pointed out that the technique of Arrival Angle or (AoA) is especially useful for location systems based on radiofrequency and generally used with groupings of antennas in phase, in which the phase difference between the different antennas of the same, allows to determine the direction of incidence of the signal.

In the publication "Review of Radar Absorbing Materials" by author P. Saville (2005), a detailed description is made of the methods and materials used to reduce microwave reflection and in U.S. Pat. No. 2015/0042502 Al describes an E.M. composed of several layers combining different materials.

PCT application WO 2013/144410 Al describes a multilayer composite material, which when applied is capable of substantially reducing E.M. reflected by a surface, when compared with E.M. incidents about her.

In U.S. Pat. No. 7,948,446 B2 an isotropic antenna is emulated; An isotropic antenna is a theoretical antenna that radiates the same amount of energy in all directions, through a grouping of antennas consisting of three dipoles that share the same cover, where the transceiver is fed through a coaxial cable and where the Transceiver can receive and send radio frequency signals in any direction or plane.

In U.S. Pat. No. 8,983,420 B2 describes a circular grouping of antennas in order to reduce interference from a radiating source in motion. The grouping of antennas comprises a receiver and several elements grouped in flat form.

In the Master thesis "Designing of a Small Wearable Conformal Phased Array Antenna for Wireless Communications" by S. Roy, 2012, the design of a group of antennas in phase is shown; which corresponds to a set of antennas where the relative phases with which each antenna is powered are changed in order to alter the radiation pattern of the set.

On the other hand, in the document "Multipath mitigation through cylindrical microstrip phased array antenna", by the authors D. Mastela et al (2006) it is pointed out that microwave-based tracking systems are very vulnerable to multipath, which leads to strong distortions in position estimates. To improve the Flight Time (ToF) measurements in environments with severe multipath the authors constructed a prototype.

 In U.S. Pat. No. 6,864,853 B2 describes the concepts of directional and omnidirectional antennas. In which there is also a structure with a variety of antennas, configured and oriented in such a way as to achieve directional and omnidirectional coverage.

 In U.S. Pat. No. 3,482,251 describes a group of speaker antennas, composed of a conic surrounded by four adjacent squares and a central transceiver that is used for monitoring. The speakers are widely used for having high directivity, gain and efficiency, broad bandwidth and are easy and economical to build. In the publication "Horn type antennas" by the authors J. Patiño et al (2011), their design is described and their radiation pattern is shown.

In US Patent No. 3,445,852 the design of an antenna for receiving or transmitting microwaves having a waveguide is disclosed. A waveguide with a geometric-tapered shape is described, which affects the amount of energy that passes through it. The 3D Bat Ultrasonic Location System, described by R. Harle and A. Beresford (2002), is based on the technique of trilateration and the time difference on arrival (TDoA). It includes TAGS attached to people or mobile objects that have an ultrasound transmitter and also a 433 MHz RF transceiver. Each TAG has an identification with a length of 48 bits and there is a network of sensors located in different locations that also have transceivers. The system is precise but it is very sensitive to multipath, as well as to the interferences that alter the quality of the signal (eg attenuations).

On the other hand, the Cricket Location System, described by Priyantha (2005), is a location system used preferably in closed places that is also based on trilateration and the difference in arrival time. The architecture of the Cricket System is composed of radio beacons, fixed and active, which have an R.F. transceiver, a microcontroller and an ultrasound transceiver and passive listening TAGS attached to the people or objects to which they want to be located.

The advantages of Cricket are privacy, since only the carrier of the listening device may or may not reveal its position, the ease of the system to scale in size, the ease of installation and the fact that a large number of devices can be used Listen, as these operate passively.

Among the disadvantages is the fact that the ultrasound signals have no identification and that they have a high reflection which gives rise to bounces and erroneous distance estimates, even with the use of inference algorithms. In addition there are limitations to use them in small places, since the differences in the arrival time between the R.F. and the waves of U.S. They tend to disappear.

In U.S. Pat. No. 7,038,584 B2 discloses a system for tracking a moving person or object within an interior space, which has a set of fixed beacons, which transmit a signal with an identification code and at least one RF transceiver , attached to the mobile object, which receives the signal from the radio beacons and determines their intensities. In addition to the transceiver, the mobile object carries a motion sensor and with the information coming from both a computer determines the position.

 In U.S. Patent No. 5,920,261 a system is disclosed that aims to plan, visualize, track and analyze physical objects such as merchandise in a store, where a transponder is attached to each object and where each transponder is periodically interrogated by a transmitter.

 The document "Intrusion Detection Systems and Subsystems" of the U.S. Nuclear Regulatory Commission, 2010, provides information regarding the design, installation, testing, maintenance and monitoring of intrusion detection systems and subsystems used for the protection of facilities.

 The U.S. Patent No. 3,691,558 describes a system for the detection of moving objects within an irradiated area and for activating an alarm in the event that the human presence is detected, comprising one or more transceivers distributed in the areas to be protected.

 U.S. Patent No. 8,159,364 B2 discloses a system to provide power wirelessly to electrical or electronic equipment, by microwave. The electricity in the network produces a magnetic field that can be directed via microwaves to a certain location, in response to a signal from the receiver located in the equipment, through a reflecting antenna and one or more transceivers.

In the international patent published under No. WO 92/08105 an innovation is disclosed for the location in which the concept of attenuation is used, which was designed to obtain the horizontal distances to a GPS satellite, to obtain the position of objects that are not within reach of satellites and determine their own position. In general terms the instrument is composed of a tripod and a level, a central bar that is born from the tripod, on which a receiver with its respective antenna is mounted, to indicate the strength of the GPS satellite signal. It also has an adjustable fixed sight, a graduated disk, a processor, a thin wing with attenuator or reflector material that vary the intensity of the satellite signal, a motor with a rotational sensor that rotates the wing around the center of the disk.

GENERAL DESCRIPTION

 Location, tracking, detection and access control can be more efficient using antenna clusters such as those of the present invention. Determining the position of people and objects has many applications such as improving security, reducing risks and others, which in general leads to increase income and decrease the costs of people and companies.

Location systems determine the position of people or objects using radio frequencies, magnetic fields, acoustic signals or other methods of collecting information, but the problem is that Rf is very sensitive to the negative effects of multipath.

This invention mitigates the effects of the multipath; that it is the phenomenon of propagation that causes the radiofrequency signals emitted by a transmitter to reach the receiver by more than one way and that are due to the reflection, refraction and diffraction of EM waves in people, objects and in general to obstacles and deviations in the layers of the atmosphere. Each one of these

This invention is based on the geometric design of the grouping and its manufacturing material to mitigate or cancel the negative effects of the multipath; indeed, the circular distribution of the same with the possibility of transmitting or receiving signals in a sectorial way and in 360 °, in one or two planes, improves the quality of the communication and allows to have a clear line of sight between the transmitter and the receiver. However, this invention preferably needs to be used with microwaves, although not in an exclusive way, since these frequencies are used in point-to-point links with directional radiation.

 In summary, this invention corresponds to a circular, flat and sectorial grouping of opening antennas especially for horn, whether pyramidal, flat E, flat H, conical and exponential, smooth and corrugated that stand out for their efficiency, directivity and gain. The grouping has n antennas and n sectors (one antenna per sector) and covers 360 ° of a plane (ID).

 The opening antennas are those that use surfaces or openings to direct the electromagnetic beam in order to concentrate the emission and reception of its radiating system in one direction and where the excitation of the antennas is achieved through the propagation of waves and not of a transmission line. Opening antennas are preferably used with microwave frequencies.

The horn antennas are waveguides that carry radiofrequency energy from one point to another and in which the cross-sectional area is gradually increasing, which is known by flare, from a rectangular or circular waveguide towards the open end or horn mouth. These horn antennas are widely used for their efficiency, high gain and directivity and for the ease of building them. The horn antennas of the grouping of antennas of this invention are distributed radially, with openings to the outside and the throats and guides inwards, deployed on a symmetrical plane and where the longitudinal axes of the speakers belong to said plane and converge towards the interior of the same, in the central point of the grouping and where the openings of the antennas are inscribed in an imaginary circle that marks the outer limit of the grouping.

The main characteristics of the antenna group described in this invention is that the horn and deep guide are made of different materials and alternate within the group. There are transmitting or interrogating antennas made of a reflective material such as metal and other receivers made of a high or fully absorbent material.

The transmitting antennas fulfill the traditional function, making versatile the direction of beam of electromagnetic waves towards a specific TAG or point. The shape and material of the receivers allows to calculate with precision the direction of arrival of the signal, Angle of Arrival, since only those that correspond to the line of sight or that are parallel to it, will access the transceiver. The signals that come from other angles and that differ from the line of sight are attenuated by the speaker absorbing material.

The absorbing material of the antenna allows to attenuate R.F. in such a way that the multipath effect is mitigated or canceled. The attenuation corresponds to the effect of how an E.M wave that propagates through a medium decreases its intensity. The power of the wave decays exponentially with distance and with the value of the attenuation constant of the material.

Absorbents are used in a wide range of applications to avoid radiation that interferes with the operation of a system and is characterized by its electrical permittivity and magnetic permeability. In many absorbents both characteristics, permittivity and permeability, can be affected by the frequency of electromagnetic waves.

 The main methods of location are the following:

- Distances and angles: Distances and angles are measured with respect to reference points to determine the position of a person or object by trilateration (distances) or triangulation (angle of arrival AoA).

- Signal characteristic: The position of a person or object is determined by measuring the intensity of arrival of an RF signal from different reference points (RSSI). Only the signal strength is measured, since the quality depends on the noise.

In relation to the first of the methods there are four techniques to measure distances from an object to a reference point; Flight time or (ToF), total flight time (RTT), difference in arrival time (TDoA) and image processing. However, all of these, with the exception of the latter, depend on the intensity of the signal and therefore are sensitive to the negative effects of the multipath.

The method of locating this disclosure considers the measurement of angles (AoA), that is, triangulation, which is possible to do with highly directional antennas such as those used in this invention. The Angle of Arrival (AoA) technique has the advantage of being more stable than the signal strength, but the disadvantage that only with antenna groupings can the position be accurately determined, unlike those based on the measurement of distances. However, the problem is that antenna groupings, including phase antenna groupings, are expensive and complex to build. The groupings of antennas in phase, are a set of antennas in which the relative phases with which each antenna is fed are intentionally varied in order to alter the radiation pattern of the assembly; Any antenna system that transmits or receives signals has two characteristics; The amplitude and the phase.

The groupings of antennas in phase are difficult to construct, since they require a good coordination between the elements of the same one in order to be able to detect the differences of phase. In addition, the antenna groupings have configurations with many fixed elements which makes them inflexible in terms of their use in different places and environments. Additionally, some of the tracking systems based on groupings of phase antennas are based on the use of the signal strength technique, which has great limitations due to multipath problems, especially in interior spaces.

For this invention, a group of antennas based on geometry and materials was chosen, since those in phase have restrictions such as coverage, costs, circuitry and its elements and especially with the multipath. It has been shown that signals that are distorted by that effect deteriorate position estimates. The grouping of antennas described is low cost, easy to build and versatile in terms of location possibilities.

In relation to the detection of people and objectives it is convenient to point out that microwave sensors are detection devices that permanently transmit a signal and at the same time are receiving the signal reflected by objects, walls and others. If there is a movement of objects or people the received signal will change its frequency slightly (Doppler effect). There are two basic configurations:

 Bistatic: They comprise a transmitter and a receiver located in a given perimeter.

 Monostatic: They comprise a transceiver.

Finally, it should be mentioned that the arrangement of opening antennas of the present invention is part of a radio beacon which also comprises a microcontroller, a main transceiver with an omnidirectional antenna, which is an integral part of this location, tracking, detection and control system. of access.

DESCRIPTION OF THE FIGURES

Figure 1 shows a graphic representation of the multipath, as well as the feasibility of reducing its negative effects using antennas with a geometric design that mitigates it.

 Figure 2 shows a plan view of the 2-A cluster; circular, flat and sectorial of antennas of this invention, with n sectors and covering 360 ° of an ID plane and where the antennas differ in their manufacturing material, the transmitters are clear 101, 103,105, 107, 109 and 111 and the dark receivers 102, 104, 106, 108, 110 and 112. In addition, a detail of the tube 145 occupying the center of the 2-B cluster is shown.

Figure 3 shows a front sectional view of the 3-A, circular, flat and sectorial grouping of antennas of Figure 2. In addition, a detail of the plunger 150 that goes inside the tube 145 occupying the center of the cluster 3- B. Figure 4 shows a plan view 4-A and front 4-C, of the grouping, circular, flat and sectorial of antennas, with n sectors and covering 360 ° in two 2-D planes, of a second preferred version in where the difference in materials of both types of horn antennas, transmitters and receivers is plotted. Also in Figure 4-B you can see a detail of the mechanism that allows you to rotate the grouping in the vertical and horizontal directions.

Figure 5 shows a group of radio beacons communicated with the TAGS 211, with access points 216 to the wireless network 220, with access controls 211 to 215 and through detectors 221 and 222.

DETAILED DESCRIPTION OF THE INVENTION

The grouping of opening antennas has among its objectives to reduce the multipath that is shown in Figure 1, it is based on a cluster of opening antennas, which operates mainly according to its geometric design and the materials used in its manufacture and that it is located in radio beacons that also include; a main transceiver with an omnidirectional antenna, a microcontroller and a battery. The antenna group consists of opening antennas, especially those of horn; of plane E, of plane H, conical, exponential and pyramidal and where you are, the latter are used by way of example in this disclosure.

 In the preferred materialization the grouping of horn antennas corresponds to one of the circular, flat and sectorial type, where the antennas are located radially, as can be seen in Figures 2-A and 3-A. The speakers next to their respective wave guides are deployed on a plane of horizontal symmetry and where the number of antennas shown in these figures, 12 elements, is only an example, since as mentioned they can be n antennas per grouping .

 The grouping comprises antennas, in this example from 101 to 112 where each of these covers each of the n sectors or angles, respectively and where the total coverage of the set is 360 ° in ID. Alternatively, clusters can be constructed that work with smaller coverages such as 90 ° quadrants or 180 ° semicircles, depending on the requirements. If the number of elements increases (n), the smaller the size of the sector covered by each of the antennas (angles).

 In the center of the horn antenna cluster there is a tube 145 whose central cross section belongs to the plane of symmetry of the cluster and whose longitudinal axis is perpendicular to it. The geometric place where the plane of symmetry intersects with the longitudinal axis of the tube corresponds to the central point of the grouping O in Figure 2-A. In addition, each of the n antennas is associated with n vertical symmetry planes that are perpendicular to the symmetry plane of the cluster; the intersection of all of them is a line that passes through the center O of the cluster and coincides with the longitudinal axis of the tube.

 Within the group the antennas are distributed using as reference three imaginary circles and one real, all concentric to the central point and belonging to the plane of symmetry of the group and whose characteristics are described below:

The imaginary circle of greater radius, among other conditions, meet the following; belong to the plane of symmetry of the grouping and intersect the vertical strokes (HE) and (KL), which are perpendicular to it. In the second imaginary circle of smaller radius, the following two conditions are met; belong to the plane of symmetry of the grouping and intersect the vertical strokes (GD) and (JM); that are perpendicular to the first and that mark the union between the throats of the horns and the wave guides.

In the least of the three imaginary circles, at least the following two conditions are met; belong to the plane of symmetry of the grouping and intersect the vertical strokes (FC) and (IN), perpendicular to the first and also mark the cross section of the antenna where the waveguide ends. The last circle is the geometric place where the outer edge of the tube 145 intersects the plane of symmetry.

 As can be seen in Figures 2-A and 3-A, the grouping of antennas of this invention is composed of n pyramid horn antennas 101 to 112; below it is possible to see, only by way of example, the relevant parameters in this type of antenna, since any horn serves the purposes of the present invention; that is to say antennas of plane E, plane H, conical and exponential. In addition to the n corresponding rectangular waveguides 121 to 132 related to each of the antennas and by a main transceiver, a microcontroller and a battery, all of them located in the center of the cluster and that receive and send signals to TAGS 211 located outside of the grouping. In general terms pyramid antennas have the following design:

 PYRAMIDAL HORN ANTENNA

The electric field component is:

¾ = -i -.— [ίφ + ί? Λ¾]

[L „- ηΝ _φ )

 Anr

[cos (cos0 + T) h] The directivity is:

One of the main characteristics of the grouping of antennas of the present invention is that there is a difference in the material from which they are made, as can be seen in Figures 2-A and 3-A; while the clear ones represent a total or highly reflective material such as metal 101, 103, 105, 107, 109 and 111, the dark ones represent a total or highly absorbent material 102, 104, 106, 108, 110 and 112 and where both Antenna types alternate sectorally within the antenna pool and where the reflective antennas are only interrogators (of the TAGS) or transmitters of radio frequency signals while the absorbing antennas are receivers of the TAGS 211 transmissions.

 The choice of the absorbent material is based on its relative permittivity or dielectric constant, the relative magnetic permeability of the same and the working radiofrequency; The equations to determine them are indicated below:

Permitivity:

E | = -

4ne ₀ R ²

10 ^" ' ² [Farads / Meer]

Equation 1; where ^ε _ο corresponds to the permittivity of the vacuum.

| E | = *

4m _r e ₀ R ² 4πεΚ ²

Equation 2: where ^E r is the relative permittivity or dielectric constant. ε— € _r 6 ₀

Equation 3: The permittivity of a material is expressed as the product of the dielectric constant and the vacuum permittivity, where r ^e is always> 1..

Permeability:

B = μΆ

Equation 1: Permeability is denoted by μ and is expressed in henry / meter. Where μο is the vacuum permeability. μ ₀ = 4πΊ0 -7 [H / m]

Equation 2: It is the vacuum permeability formula.

 Equation 3: The permeability of a material μ is represented in terms of its relative permeability μΓ that relates the permeability of the medium to that of the vacuum.

 Returning to the geometric design of the grouping in Figure 2-A, it can be seen that the rear part of the rectangular mouths of the waveguides terminate in the tube 145, while the cavity thereof extends into the interior of the tube through a slot in its wall. The grooves in the tube are the projection of the cross-section of the waveguide on the tube walls. In summary, all the inner mouths of all the wave guides coincide with all the grooves that are located around the tube. An important detail for the adjustment of the waveguides with the tube is that the horizontal walls, parallel to the plane of symmetry, of the rear mouths of the waveguides are concave, as shown in Figure 2-C, so that fit with the convex wall of tube 145.

 Inside the tube and in the center of the cluster there is a metallic plunger 150 that rotates on a central axis 155 and is formed by a second metal tube and two metal caps of the same material, a top 152 and a bottom 153, both sealed, inside of which there is a main transponder 140 with a microcontroller 141, an omnidirectional antenna 142 and a battery that feeds them. The radio frequency of operation of all transceivers, both of the beacons, and of the TAGs, of the access points to the network and of the access control, which are part of this system may be microwave, although not exclusively , since they are the most appropriate for radio links with sight lines and horn antennas.

 Plunger 150 is made of metal, since otherwise, during transmission, it would partially absorb 0 - totally the waves with which the reflecting or interrogating horn antennas have to be fed. During transmission the groove 154 of the plunger 150, which is rotating, must sequentially coincide with each of the grooves located around the tube 146 and which are associated with a particular metal horn; Functionally the plunger becomes part of the corresponding waveguide, although the discontinuities between the different metallic elements (plunger, tube and waveguide), alter the propagation of the wave.

 During the reception of signals, the groove 154 of the plunger 150 must coincide with the openings around the tube 146 associated with one of the absorbent horns 102,104,106,108,110 and 112. The piston is made of metal but the reflection inside is low, since the Waves are attenuated by the absorbent material or voided by the angular arrangement of the speakers.

An important element is the size of the absorbent horns 102, 104, 106, 108, 110 and 112, since the larger the size, the greater the flare surface and the absorption surface and the greater the attenuation of the EM waves that do not match the sight lines. In addition there is an exchange between the size of the antenna and the accuracy of the grouping in the measurement of angles; The higher the number of speakers, the more precise. In the lower part of the plunger 150 there is a cylindrical bar 155 which allows its rotation and whose longitudinal axis is perpendicular to the plane of symmetry of the grouping and coincides with the longitudinal axis of tube 145 and passes through the central point of the grouping. At its lower end this bar has a gear 156 parallel to the plane of symmetry of the grouping, through which and from a second gear 157 and a second shaft 158, the pin 150 is connected to a servomotor with encoder 159, which rotates 360 °, depending on the programming of the 141 microcontroller.

 In short, when the piston 150 rotates on its axis 155, the groove it possesses 154, coincides sequentially with each of the openings of the central tube 145 and through them coincides with all wave guides and through them with all the antennas, transmitters or receivers. In this regard it is important to avoid R.F. between the plunger grooves (154) and tube 146 to prevent exposure of the remaining antennas.

During transmission the transponder 140, the microcontroller 141, the omnidirectional antenna and the battery rotate within the plunger 360 ° stopping sequentially and programmed according to the microcontroller signals, on the reflective antennas, to transmit signals to the TAGS. During reception, the plunger 150 also rotates in 360 ° stopping at the absorbing antennas to receive the signals of the TAGS 211. The geometric design of the present invention allows that from an omnidirectional antenna, which radiates in every direction can be irradiated in one direction, taking advantage of the advantages of horn antennas in this regard.

 Covering the central tube, the wave guides and partially the horns there is a circular cover 160 parallel to the plane of symmetry of the grouping that joins the set of antennas and whose central point belongs to the longitudinal axis of the tube. Below the grouping there is a second circular cover 161 which also covers the waveguides and partially the antennas but which unlike the upper cover has an opening in the center that lets the tube 145 pass so that it extends towards the lower part of the grouping.

 A second preferred embodiment, Figure 4, 201, is that in which the antenna group has the same type of elements and the same geometry and components, but its plane of symmetry is perpendicular to that described above. The advantage of this version is that it allows 360 ° coverage in two planes, since using a pair of 159 and 202 servomotors and a structure, turns in the vertical and horizontal direction are achieved, which emulate the coverage of the sectors of a sphere.

 The center of this second preferred materialization 201 is occupied by a tube 145 perpendicular to the plane of symmetry thereof, closed on both sides, inside which a closed plunger 150, composed of a tube and two covers, where the longitudinal axes is located of the tube and the plunger are coincident. The plunger has two half shafts 155, which are joined with the plunger on the outer side of the covers and whose longitudinal axes coincide with those of the tube and the plunger. The tube has grooves around it that coincide with the cross sections of the waveguides of the cluster 146 and where the plunger has a single groove 154.

The plunger is connected to a servomotor 159 through a gear 156 having one of the half shafts and a second gear 157 having the axis of the servomotor 158. This servomotor moves the grouping in a vertical direction as can be seen in the Figures 4-B and 4-C depending on the microcontroller signals. A second servomotor also connected to the structure that supports the grouping of antennas allows it to move horizontally and where between the two servomotors the sector coverage of a sphere can be emulated. In summary, the system corresponding to this invention comprises four components; the mechanic, the electronics, the communications and a processing unit. The mechanical component has a servomotor 159, a pair of axes 155 and 158, a pair of gears 156 and 157, a tube 145 and a piston 150 and where the mechanical component is related to the electronic and communications, by means of a microcontroller 141 and a main transponder 140, respectively, which are located within the plunger 150 and with the processing unit through both and the transceivers of the access points 216 to the wireless local area network 220.

 The communications component comprises the main transceiver 140 of the radio beacons, the secondary transceivers of the TAGS 211, the omnidirectional antenna 142, the transceivers of the access points to the wireless network 216, the transceivers of the access control 212, the transceivers for the bi-static type detection 222, the horn antenna array 101 to 112 and its corresponding waveguides 121 to 132. Where the communications component relates to the mechanic through the main transceiver 140 located within the plunger 150 and which is moved by servomotor 159, with the electronic component through microcontroller 141 with which it is connected directly and with all remaining microcontrollers wirelessly and with the processing unit through network access points 217.

 The electronic component comprises the microcontrollers 141 of the radio beacons 210, those of the TAGS 211 and those of the access control where all are related to each other and to the processing unit 217 wirelessly through the main transponders of the radio beacons 140, the secondary ones of the TAGS 211 and those of the access control 213; with the mechanical component it is related through the servomotor 159 and with the data processing unit 217 through the access points 216 of the wireless local area network 220 in a two-way communication and where the local area network 220 is characterized by its topology, protocols and connection means; It includes the server 217, the monitoring stations 218, the network card and the access points 216 and where through the INTERNET you can access the server and make modifications in the same way as with the microcontrollers through the access point to the wireless network 220.

 The access control component comprises microcontrollers 212, transponders 213 and actuators 214 and relates to the electronic component through the microcontrollers, with the communications component through the transponders, with the mechanic through the physical elements 215 which it has and with the process unit 217 through the transponders of the access points to the network 216, where the system administrator can give them necessary identification information to the access control in relation to the attributes of people or objects.

In summary and in relation to the location and monitoring of people and objects, the microcontrollers of the radio beacons periodically send identification signals to the TAGS, through their main transponders and where the TAG responds to said signal through the secondary transponders with the information contained in his memoirs. By means of the grouping of antennas of the present invention, the angles of arrival to the radio beacons can be obtained; said information is transmitted to the server, through the access points of the local area network so that it determines the position of the GAD, through triangulation, with the information of at least two radio beacons and using the calculation algorithm and where The server can also save the relative traces of the positions in a database. In relation to the detection, assuming a bi-static microwave system, communication between microcontrollers and between them and the server allows the angles and departure time of the transmissions of all radio beacons to be known. In addition, the positions of the detectors 122, microcontrollers with tranceptors, of the perimeter that receive them as well as their arrival angles, in relation to the position of the beacons are known. With the information of at least two beacons, the position of a particular TAG can be determined, through the triangulation technique by means of a calculation algorithm. If the microwave system is mono-static, the angles and departure times of all transmissions are known, as well as the direction of arrival of all bounce waves in people and objects, with which through triangulation it can be determined the position of the latter.

BIBLIOGRAPHY

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 8,159,364 B2 4/2012 Zeine

 8, 983,420 B2 3/2015 Musselman and Lee

OTHER PATENTS

WO 1992/08105 5/1992 Wilkund

WO 2013/144410 3/2013 González et al.

OTHER PUBLICATIONS

 - R. Mautz, "Indoor Positioning Technologies", Doctoral Thesis, Institute of Geodesy Zurich, 2012.

- M. Kossel, "Active Microwave Tagging System", Doctoral Dissertation, Swiss Federal Institute Technology, Zurich, 2000.

- S. Roy, "Designing of a Small Wereable Conformal Phased Array Antenna for Wireless Communication", Master Thesis, North Dakota State University, United States. - D. Mastela et al., "Multipath Mitigation Through Cylindrical Microstrip Phased Array Antenna", University of Freiburg, Germany, 2006.

 - P. Saville, "Review of Radar Absorbing Materials", Technical Memorandum, Defense Research and Development Canada, 2005.

 - R. Harle, and A. Beresford "The Bat System Ubiquitous Computing in Action", Workshop "Laboratory for Communications Engineering", Cambridge, England, 2002.

 - N. B. Priyantra, "The Cricket Indoor Location System", Doctoral Thesis, Massachusetts Institute of Technology, 2005.

 - U.S. Nuclear Regulatory Commission document, "Intrusion Detection Systems and Subsystems", 2010.

- H. Chung Chen, "Determining RF Angle of Arrival Using COTS Antenna Arrays; a field evaluation", Military Communications Conference, IEEE Digital Library, 2012.

 - J. Patino, "Antennas and Propagation", Faculty of Engineering, Francisco José de Caldas District University, Colombia, 2013. www.slideshare.com.

Claims

1. -A grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane, CHARACTERIZED because the grouping of antennas 100 is displayed on a plane of horizontal symmetry, within a topological space, and is inscribed in an imaginary circle where the horn antennas are located in circular, flat and radial form; in the center of the group there is a tube 145 whose longitudinal axis is perpendicular to the plane of symmetry and where the intersection of its longitudinal axis with the plane corresponds to the center of the antenna group.

2. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the grouping comprises any kind of aperture antennas including the horn antennas.

3. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the grouping of antennas 100 has a 360 ° coverage in a plane when it is moved at least by a servomotor 159.

4. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and towards it, of radiofrequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the antenna array has a 360 ° coverage in two planes when it is moved by at least two servomotors 159 and 202 and where a structure He holds it.

5. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the grouping of antennas comprises opening antennas 101 to 112 having waveguides and where their mouths look outward from the cluster while their Gorges and the waves 121 to 132 guide the center inside the cluster.

6. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and towards it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the prolongation of the longitudinal axes of the antennas towards the interior of the cluster converges towards the center of the same O.

7. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to the same, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED by having a tube whose longitudinal axis intersects the plane of symmetry at the central point of the grouping O and that is perpendicular to said plane.

 8. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and towards it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the tube is connected to the rear parts of the waveguides whose cavity extends into the interior through grooves in its wall 146 .

 9. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the grooves in the tube 146 are located around it coinciding with each of the waveguides 121 to 132.

 10. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and towards it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because inside the tube there is a piston 150 that rotates on a central axis 155 that ends in a gear 156, which is connected with a servomotor 159, through a second gear 157 and a second shaft 158 to a servomotor 159, where the servomotor rotates according to the programming of the microcontroller 141.

 11- The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to the same, of radio frequency transmissions and comprising n opening antennas, n guides waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the plunger 150 has a groove 154 that coincides with each and every one of the grooves arranged around the tube 146 when rotating sequentially therein.

 12. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and towards it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because within plunger 150 is a main transceiver 140 that communicates with secondary transceivers of the TAGS, a battery and a microcontroller 141, wherein this The last one has programmed the rotation sequence of the servomotor 159.

13. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and towards it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED in that the transceiver 140 sequentially feeds the transmitting antennas 101, 103, 105, 107, 109 and 111, through the wave propagation pathway RF

14.- The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and towards it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; one antenna per sector and covering

360 ° in a plane according to claim 1, CHARACTERIZED in that the information about the position of the transponder (s) of the TAGS 211 located in the topological space is refreshed as a function of the angular velocity of the piston driven by the servomotor 159.

15.- The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and towards it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because one more of the antennas are made of a reflective material 101, 103, 105, 107, 109 and lll, while the remaining ones are made of an absorbent material, 102, 104, 106, 108, 110 and 112.

16. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the reflective antennas 101,103,105,107, 109 and 111 are used with the main transceiver 140 during the transmissions of the radio beacons 210, while the absorbents 102,104,106,107, 108, 110 and 112, are used with the transceiver during the reception of signals from the TAGS 211.

 17. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED in that the antennas made with reflective materials 101,103,105,107, 109 and 111 and absorbent 102,104,106,107, 108, 110 and 112, respectively, alternate in their location within of the arrangement

 18. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because each of the antennas of the group 101 to 112, has a certain scanning angle, either for transmission or reception, where the Total sum is 360 °.

19. - The grouping of opening antennas 100, circular, flat and sectorial to mitigate the multipath and measure the angles of arrival and departure, from and to it, of radio frequency transmissions and comprising n opening antennas, n guides s waves and n sectors; an antenna per sector and covering 360 ° in a plane according to claim 1, CHARACTERIZED because the greater the number of antennas, the lower the scanning angle per antenna and the greater precision in determining the angles of arrival or departure.

20.- A system to determine the presence or absence of people or objects, by means of a group of opening antennas according to all the previous claims, in a topology space) and at a particular time and where it is understood by absence that are not in a position within a topological space or that lack an attribute and where the grouping of antennas 100 measures the angles of arrival and departure of radiofrequency waves and where the system aims to make more efficient the location, monitoring, detection and access control and comprising the following elements: a. - Two or more radio beacons 210 that receive or transmit radio frequency signals, that are located within a topological space and that can determine the arrival angles of transmissions from TAGS 211 attached to people and objects in the environment, as well as determine the angles of the transmissions made thereto and comprising the following elements a main transceiver 140 with an omnidirectional antenna 142, an array of opening antennas 100, a microcontroller 141, a battery and the circuitry b. - At least one TAG 211 that is designed to be attached to people or objects that have one or more attributes, that are located in the space indicated above and at a specific time, which they have; a secondary transceiver, which receives and transmits identifying signals with an omnidirectional antenna, a microcontroller, a battery and the circuit c- One or more processing units 217, which process the capture of information, its interpretation and the presentation of the results. In addition to one or more monitoring stations 218 and peripheral devices connected through a wireless local area network 220 with multiple communication protocols and with one or more access points 216; where the processor 217 and the workstations 218 have an operating system, with a program to create databases that allow storing traces of the TAG positions, with a program to manage a local area network with mobile nodes, with a program that allows to visualize and change the topology, with a program that allows synchronization of clocks in the network and at least one program that includes the following applications:

- Manage the microcontroller network; of radio beacons, of TAGS 211 of network access points and of access control,

- Have a calculation algorithm,

- Update the time of all the elements of the wireless local area network,

- Create users and assign them an identification and codes according to their attributes. d) A central memory for storing data 219, for access by an application program executed in a data processing system; comprising a data structure stored in memory; where the data structure includes information resident in a database used by the application program for various purposes, e) One or more microcontrollers 212 with actuators 214; as well as physical access elements such as motors, electric locks, doors, barriers and other 215, for access control, f) One or more detectors (221 and 222), for the detection of people and objects,

21.- A method for locating people or objects and / or monitoring them, within a given topological space and time, by means of a group of antennas of opening antennas 100, according to all the preceding claims, which are located in two or more radio beacons 210, which measure angles of arrival and departure of RF signals and where the persons or objects, with determined attributes, have TAGS 211 attached that are capable of responding to an identifying signal of the radio beacons, with a signal which contains its own identity, time and attributes and that includes the following acts and steps: a) Making the physical and logical design of the wireless local area area network 220 taking into consideration the mobility of some of its elements, with a program that allows to visualize and change the topology,

b) Synchronizing the clocks of all the elements of the wireless network, with a program that allows synchronizing the clocks.

c) Developing a system administration program that includes applications to create or. cancel users, assign identifications and codes, define attribute tables and codes, assign transmission intervals and refresh times for presentation information, assign angular speeds of servomotors 159 and hence of pistons 150, establish activation sequences of the physical elements of access control and others,

d) Programming all the microcontrollers of the system, so that they can communicate in both directions, with other units such as microcontrollers, peripherals or with the processing unit, directly or through INTERNET through interfaces,

e) Evaluating the requirements and making the logical design of the system and developing one or more programs that capture the information, interpret and present it,

f) Programming the microcontrollers of the beacons 210 so as to rotate the servomotor 159 and hence the plunger 150 of the cluster, at speeds defined by the system administrator to refresh the information,

g) Programming the microcontrollers of the radio beacons 210 so that they can transmit identifying signals, sequentially and at time intervals defined by the system administrator, recording the output angles of the transmissions to the TAGS 211 associated with people and objects,

h) Programming the microcontrollers of the radio beacons 210 so that they can receive sequentially identifying signals of response of the TAGS 211 at time intervals defined by the system administrator, recording the identity, attributes, angles and arrival times of the transmissions made by TAGS 211 associated with people and objects,

i) Programming, for detection purposes, the microcontrollers of radio beacons 210 so that they can transmit identifying signals to people and objects and receive rebounds from them, in static mono systems, recording the exit and rebound angles of said transmissions as well as the respective hours, j) Programming the TAGS 211 microcontrollers so that they receive the identifications of the radio beacon transmissions and record their arrival times, k) Programming the TAGS 211 microcontrollers so that they transmit identifying signals to the beacons and record their departure times,

I) Programming the microcontrollers of the access control so that through the actuators 214 they activate the physical elements of the latter 215, depending on the identity and attributes of people and objects according to the instructions of the system administrator through the unit of processing 217,

m) Programming the detectors (221 and 222) of people and objects, so that in the static bi systems, the transceivers receive the signals of the transmissions and record the identity of the beacon 210 and the time of arrival of the radio beacon, n) Storing in the central memory, through the access points to the wireless local area network, information comprising identification, arrival and departure angles of the beacon radios 210, hours and attributes of people and objects, hours of activation of the physical elements of access control and fingerprints of all positions within the topological space, depending on the angles determined by at least two radio beacons, or) Developing a computer program that includes a calculation algorithm that accesses memory data and through them you can determine by triangulation the position of people or objects within the topological space at a certain time,

22. - The method according to claim 21, wherein the location and tracking of people or objects is done using TAGS 211 that receive and respond to radio frequency identifying signals from and to beacons 210 and where the latter, by means of a grouping of opening antennas 100, can determine the arrival angles and the hours of said transmissions. This information is transmitted to the processing unit, through the access points to the wireless network 220, so that by complementing it with the information of at least one more beacon and by means of a calculation algorithm and the triangulation technique, it can be determine the location of people or objects and track them.

23. - The method according to claim 21, wherein the access control of people or objects is done using TAGS 211, which receive and respond to both radio frequency identification signals and signals from and to radio beacons 210 and control controls. access (213 to 215) and where the former can, through a cluster of opening antennas 100, determine the departure and arrival angles and the hours of said transmissions and in which the latter can activate control devices of access (213 to 215) based on the information provided by the TAGS 211 and the processing unit 217. This information is transmitted to the processing unit, through the access points 216 to the wireless network 220, for that by complementing it with the information of at least one more beacon 210 and by means of a calculation algorithm and the triangulation technique, the location of person can be determined as or objects and allow them access to a specific place.

24. - The method according to claim 21, wherein the detection of people in a bistatic system is done through radio beacons 210 and detectors (221 and 222), comprising a transceiver and a microcontroller, which receive and they transmit identifying signals through radio frequencies and where the former, through a group of opening antennas 100, can determine the departure angles and hours of their transmissions and where the detectors receive them at a given time and transmit them to the processing unit 217 and where the calculation algorithm assumes that there is a person or object in a certain direction when the transmission of the beacon does not reach the detector at a particular time and where this information is complemented with that of the minus another beacon 210 to determine the presence of people or objects in a position.

25. - The method according to claim 21, wherein the detection of people in a mono-static system is done through radio beacons 210 that receive and transmit radio frequency identifying signals and where these, by means of a group of opening antennas 100, can determine the angles of departure and the hours of their transmissions as well as the angles of arrival with the hours of the bounces of the same in people and objects and where the beacons 210 can transmit this information to the processing unit 217 and where the latter complements it with the information of at least one other radio beacon to establish the presence of people or objects.