MXPA00000213A - Dual multitriangular antennas for gsm and dcs cellular telephony - Google Patents

Abstract

The dual multitriangular antennas (AMD) of the present invention can be applied mainly to base stations of both cellular telephone systems (GSM and DCS). They provide radioelectric covering to any user of a cell operating in any of the two bands or in both simultaneously. The object of the invention is to provide an antenna of which the radiant element is comprised basically of various triangles joined exclusively by their apex. The function of the antenna is to operate simultaneously in the bands of the radioelectric spectrum corresponding to the cellular telephone systems GSM 890 MHz - 960 MHz and DCS 1710MHz - 1880 MHz.

Description

¿ "DUAL KULTITRIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY" More specifically, the invention relates to antennas formed by a set of unique triangles by their vertices. that simultaneously cover the bands of cellular telephony GSM of frequency 890 MKz-960 .MHz and DCS of frequency 1710 MHz - 1880 MHz. The antennas began to develop at the end of the last century since James C Maxwell in 1864 postulated the fundamental laws of electromagnetism. It must be attributed to Heinpch Hert? in 1886 the invention of the first antenna with which it demonstrated the transmission in the air of the electromagnetic waves. Already in the twentieth century and the early sixties appear the first frequency independent antennas (EC Jordán, GA Deschamps, JD Dyson, PE Mayes, "Developments in broadband antennas", IEEE Spectrum, vol.1 pp. 58-71 , April 1964, V: H: Rumsey, "Frequency - Independence! antennas", New York Academic, 1966; RL Carrel, "Analyeis and? esign of the log-periodac dipole array", Tech Rep. 52, University of Illinois Aptenna Lab., Contract AF33 (615) ~ 6079, October 1961, PE Mayes, "Frequency independent antennas and broad-band derivatives thereof", IEEE prsc, vol.80, n2 i, January 1992, proposing propellers, spirals, cones and clusters , logoperiódicas for the realization of broadband antennas.Frequently, in 1995 the antennas of fractal or multifractal type were introduced. {}. It must be attributed to BB Mandelbrot in his book The fractal geometry of nature, WH Freeman and Cía 1983, the coinage of the terms fractal and mult fractai) antennas that by themselves u geometry presented a multifrequency behavior and in some cases a small size, such as those described and fi they claim in the Patent of Invention ne 9700C4e of the same tituiar. The antennas described here have their primitive origin in said fractal type antennas. The object of the invention is an antenna whose radiating element consists basically of several triangles joined exclusively by their vertices. The function is to operate simultaneously in the bands of the radio spectrum corresponding to the GSM cellular telephone systems S90MH2-960 MHz and DCS 1710 MH2-13SC MHz. At present, the GSM system is used in Spain by Telefónica operators ( Movietar system) and AIET2L. It is foreseen that the DCS system will come into operation in mid-1998, with said or other operators opting for an operating license in the corresponding bank between 1710 MH2-I88OMK2. The multi-trinary antennas which are the object of the present invention (hereinafter AMD) have their main application in the bae stations of both cellular telephony systems (GSM and DCS), giving raeoelectric coverage to any user of a cell operating in any of the the two bands or both simultaneously. The conventional antennas for the GSM and DCS systems operate exclusively in a single band, which requires two antennas in case of wanting to cover both center bands of the same cell. Since the AKDs operate simultaneously in the two bands, it is completely unnecessary to use two antennas (one for each band), with which the cost of implementing the system is reduced and the environmental impact on the urban and rural landscape is minimized. The fundamental characteristics of this type of antennas are: - Its multitangular form constituted by three triangles joined by their vertices, which in turn jointly form a triangular structure of superior size. - Its behavior raa olecctpco 'input impedance and radiation diagram) that is sufficiently similar in both bands (GSM and DC.) As to meet the technical specifications for each of the two systems simultaneously.? Difference from other antennas, the behavior is obtained in the AMD through a single radiant environment; ei elemente muititrianguiar. This limits the antenna greatly, reducing its cost and size. AMD antennas are presented in two versions adapted to two specific situations - a first version is omnidirectional diagram for horizontal mounting on roof, from now on (AMD1) and a second version with sector diagram for vertical wall mounting on wall or tube,? e now onwards (AMD2). In the first case, the ultitriangular element is mounted in a morenopolo configuration on a conductor ground plane, while in the second case the multitriangular element is mounted in a patch-like configuration, parallel to the conductive ground plane. The dual multitriangular antennas recommended for cellular telephony consist of three fundamental parts: a muit ^ triangular conductive element, a connection network that mterconetta the multitriangular element with the access connector the antenna and a conductor ground plane. The distinguishing characteristic of said antennas is the radiant element formed by the union of three triangles. The triangles are joined by their vertices so that the assembly in turn has a triangular shape. The radiating element is made of a conductive or superconducting material. By way of example, although not limiting itself to them, the multitangue structure can be constructed in copper plate, brass or in the form of printed circuit on a dielectric substrate, The fundamental mission of the connection network is, first of all, to facilitate the physical interconnection between the multitriangular element and the connector? and the antenna and secondly, adapt the natural impedance of the muititriangular element to the impedance (typically 50 Osm) of the cable that connects the antenna and equip the transmitter / receiver. The conductor earth piano has the mission, together with the multitriangular element, of configuring the anteric to obtain the appropriate form of the radiation beam. In the AMDl model. the multipath element is mounted perpendicularly to the ground plane, which confers an omnidirectional diagram in the hcrieontai plane (taking horizontally said flat plane). The shape of the ground plane is not decisive, although the circular shape is preferred because of its radial symmetry, which emphasizes omnidirectionality. In the AMD2 model, the ultitrianguide element is mounted parallel to the ground plane, which gives the antenna a sectoral diagram. Additionally, metal fins perpendicular to the plane and earth can be mounted on both side edges. Said fins contribute to narrowing the radiant beam in the horizontal plane, reducing its width by increasing the height of the fins. As for the type of metal to be used, it is not important from the point of view of readjustment, although for the AMDl model aluminum will be chosen preferably because of its lightness and good conductivity. The dual behavior of the antenna, ie the repetition of its racioeléctricae characteristics in the GSM and DCS channels is obtained thanks to the characteristic shape of the triangular element. Basically, the frequency of the first operating band is determined by the height of the triangular perimeter with the structure, while the frequency position! of the second band is determined by the height of the lower solid metal triangle. Other details and characteristics of the current Patent application of Invention will become evident in the traps'cursc of the description that follows, in which reference is made to the figures included in this report in the accompanying documents. to be represented, the details referred. These details are given by way of example, making reference to a possible case of practical realization, but not limited to the details presented therein; therefore this description should be considered from an illustrative point of view and without limitations of any kind. Following is a detailed account of the main elements cited in the present description; (10) multitangular dual or nidirectional antenna, (11) multitriangular radiant element, (12) connection network, (13) connector, (14) ground plane, (15) adaptation network, 815) rigid foam, (17)} ultitriangular antenna sectorial, (13) triangular hole, (19) upper triangles, (20) lower triangle Figure nS 1 details the structure of an omnidirectional antenna (10) (AMDl) .The antenna is mounted perpendicular to the piano Figure 2 shows the structure of a sectoral antenna (17) (AMD2), clearly distinguishing the multi-riangular radiant element (11), the ground plane .'14) and the network of connection (12), the antenna (17) is mounted perpendicular to the ground plane (14). Figure 3 details two specific embodiments of the AMD1 and AMD2 antenna models, respectively. Figure nS 4 summarizes the radioelectric behavior of the antenna in the graphical GSM bands (a. And graphical DCS ib) Figure 5 is a typical radiation diagram in the GSM and DCS bands, both conserve the bilobal structure in the vertical plane and an omnidirectional distribution in the horizontal plane. Figure 6 is a specific embodiment of the dual sectorial uititriar.gular antenna (AMD2). Fig. 7 shows the radioelectric behavior of a specific embodiment of a dual-triangular antenna in which the SWR can be seen in GSM and DCS, typically below 1.5. Figure 3 shows the radiation diagrams for different types of antenna, GSM and DCS. The following describes two particular modes of operation (AMDl and AM 2) of the dual multitriangular antenna. The AMDl model (10) consists of a dual multitriangular monopod with omnidirectional radiation diagram in the horizontal plane. The multitriangular structure is formed by a copper plate of 2 mm thickness, with an external perimeter in the form of an equilateral triangle of 11.2 cm. Tall. To said triangular structure a triangular hole (18) is made, and height 36.6 cm. and inverted position with respect to the main structure, originating three triangles (19-20) joined together by their vertices, see figures nQ 1 and 3. Of those three triangles, the largest (20) is a triangle also equilateral height 75.4 cm. The multitriangular element (11) is mounted perpendicularly on a ground piano (14) of circular aluminum and 22 cm. diameter. The structure is supported by one and two dielectric posts, so that the vertex farthest from the central hole of the structure 5 is raised to a height of 3.5 mm. with respect to the center of the circular mass plane (14). Both points, the vertex of the antenna and the center of the .tiasa plane (14), constitute the terminal where the connection network (12) will be connected. The antenna (10) is sn that resonant point in the central frequencies of the GSM and DCS bands, presenting a typical impedance of 250 Ohms. The separation between plane? E mass (14) and radiant element (11) will depend on the type of connection network (12) to be used. The connection (12) and adaptation network is a broadband impedances transformer formed by several sections of transmission lines. In the particular case described here, the network is formed by two sections of transmission line and electric length equal to a quarter of a wavelength at the frequency of C 1500 MHz. The characteristic impedance of the transmission line closest to the The antenna is 110 Ohms, while the second line has a characteristic impedance of 70 Ohms. A particular version of said connection network is a mierostrip type line on a 3.5 mm substrate. of thickness type rigid foam (dielectric allowance 1.25) of dimensions 62.5 x 2.5 mm. in the first section and 47 mm. x 8 mm. in the second. The end of the opposite network to that of the antenna is connected to an axial connector of 5C Ohms, mounted perpendicularly, 0 to the ground plane from the rear face. Preferably, an "N" -type connector (haoitual on GSM antennas) will be used -The antenna has a single connector for both bands; its conversion to an antenna with two connectors (one for each band) will be achieved by adding a conventional piexcra network. Optionally, the antenna can be covered with a radome dielectric transparent to electromagnetic radiation, whose function will be to protect the radiating element and the network? E connection? E external aggressions. Several conventional techniques can be used for roof anchoring. As an example, three holes in the perimeter of the ground plane for screw anchoring. Figure Q 4 shows the steady wave relation ROE in both bands, GSM and DCS, observing that ROE 1.5 in the whole band of interest. Figure 5 shows two typical radiation diagrams. Can you observe omnidirectional behavior in the horizontal plane and a typical bilcbular diagram in the vertical plane, given the typical directivity of the antenna 3.5 d3? in the GSM band and 6 dBi in the DCS band. To emphasize the functioning of the antenna, the behavior is very similar in both bands (both in ROE and in diagram), which makes it a dual antenna. The AMD2 model (17) consists of a dual multitriangular patch type antenna with a sectorial radiation diagram in the horizontal plane. The multitriangular structure (11) (the antenna patch) is formed by a printed copper foil on a standard fiberglass printed circuit board, with an outer perimeter in the form of an equilateral triangle of 14.2 cm. Tall. Said triangular structure (11) is printed leaving a central triangular zone (IS), height 12.5 cm, free of metallization. and inverted position with respect to the main structure. The structure thus formed is composed of three triangles joined by their vertices, see figure n2 6. Of these three triangles the largest (20) is an equilateral triangle of height 10.95 cm. , see figure nS 2. The muititpangular parcne (11) is mounted parallel to a ground plane (14)? e rectangular aluminum? e 20 x 15 c The separation between the patch and the ground plane is 3.5 c. of separation that is maintained with four dielectric spacers that act as a support, not shown in figure n 2 2. On the two sides of the ground plane (14) fins of rectangular section and 4 cm are mounted. of height that narrow the beam of radiation in the horizontal plane. The connection to the antenna is made at two points, i is first located er. bisector to 16 mm. of the vertex and constitutes the point of feeding in the DCS band. The second one is located in any of the two symmetrical triangles of the structure, keeping a separation of 24 mm. in the horizontal direction with respect to the outer vertex and a separation of 14 mm. with respect to the longer side in the vertical direction, constituting the feeding point in the GSM band, the connection to these points is made by a 1 mm wire. section, mounted perpendicular to the patch. At the GSM point the wire is welded at one end to the patch and at the other end to the circuit that connects the radiating element and the access connector. In the DCS band, the wire consists, for example, of the central conductor of a 50 Ohm coaxial cable, which external conductor is connected to the rear face of the ground plane, leaving, nevertheless, a circular ring of air? & 4, 5 mm. Move around it, so that there is no direct contact between the driver and the patch. In this case, the coupling between conductor and patch is capacitive type. To keep the thread centered in the hole of the patch, a rectangle of rigid foam (16) of ba to dielectric permittivity (permittivity - 1.25) can be adhered to the inside face of the patch, to which a hole of 1 mm will be made. that will guide the coniuctor hile to the center 3the hole? the patch. In this case, said hole will expand by 4.5 mm. at 5.5 mm. to compensate for the effect of the capacitive effect introduced by the rectangle foam (16). In case of using other materials with a dielectric permitivity other than 1.25, the hole will be conveniently resized to adjust the zone and adaptation to the DCS band. The interconnection between the GSM power point and the connector and the access (13) to the antenna will be made through an a? Aptation / transformation? Network and impedances (15), see figure n <; 5 3. This network will basically consist of a transmission line with an electrical length equal to a quarter of a wavelength of 925 MHz and a characteristic impedance equal to 65 Ohms. At one end, the line is welded to the wire that is connected to the multitangular patch and at the opposite end is soldered to a N-type connector (13: mounted on the rear face of the ground plane.) Optionally, the connector (139 can be replaced by a 50 Ohm transmission line section (for example, a semi-rigid coaxial cable) with a connector at the opposite end, which allows the position of the connector l to be independent of the location of the transformer network Another particular version of the a? Aptation network will consist of a line? E transmission of 50 Ohms of, suitable length to present a conductance of 1/50 Siemens (a cable type icroaxial, for example), in which it will be inserted a parallel stub (another line of 50 Ohms? and the appropriate length) that would cancel the reactance reante to the exit of the first line.

To increase the insulation between the GSM connector and the DCS, a parallel stub with an electrical length equal to half a wavelength will be connected to the base DCS connector on the DCS connector and terminated in open circuit. Similarly, in i = base of the GSM wire a parallel stub terminated in open circuit of electrical length slightly greater than a quarter wavelength may be connected to the center frequency of the GSM band. Did stub introduce a capability? at the base of the connection that can be adjusted to compensate for the inductive residual effect of the conductor. In addition, said stub presents a very low impedance in the DCS band, which contributes to increase the isolation between connectors in the band. In figures nS 7 and e the typical radioelectric behavior is shown e is a concrete embodiment of dual multitriangular antenna. In Figure No. 7, the ROE is shown in GSM and DCS, typically below '1.5. The radiation diagrams in both are shown in figure nS 3. It is clearly observed that both antennas radiate through a main lobe in the direction perpendicular to the antenna and that in the horizontal plane both diagrams are of the sectorial type, with a beam width typical to 3d3 of S5S. The typical directivity in both bands is 8.5 dB. Described sufficiently in what consists the present Patent of Invention, in correspondence with the attached pianos, it is understood that any modifications of detail that may be considered convenient may be introduced in them, provided that the variations that are introduced do not alter the essence of the Patent. which is summarized in the following Claims.

Claims (1)

1. CLAIMS - "DUAL MULTITRIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY" of which are used by the base stations? And both systems? Cellular telephony,? Or electrical radio coverage to any user, constituted by a radiant element of conductive or superconducting material, a connection network and a ground plane characterized in that the radiant element has a uititriangular shape, which is an external perimeter structure in the shape of a triangle, constituted by several triangles joined by their vertices. 25 - "DUAL MULTI7R1ANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY" according to the claim characterized in that the multitriangular element is formed by three triangles joined by their vortices. 33 - "DUAL MULTITRIANGULAR ANTENNAS FOR CELLULAR TELEPHONY GSM AND DCS "according to the li and 23 claims characterized in that the ultitriangular element is mounted perpendicular to the ground plane in an onopod type configuration 5 -" DUAL MULTITRIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY "according to the claim characterized in that the radiation pattern of the antenna is omnidirectional in the horizontal plane and of bilobal section in the vertical plane in the GSM and DCS bands 53 - "DUAL MULTITRIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR PHONE" according to 33 and 4.3 characterized claims in which the antenna is mounted horizontally with the ground plane parallel to the ground, to cover with its omnidirectional diagram a cell of the GSM and DCS systems 6i - "DUAL MULTITRIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY. 'according to the 33 and 43 claims characterized in that the multitriangular element has an external perimeter in the shape of a triangle equilateral of 11.2 cm *** of height and that the greater of the three triangles that form the structure is an equilateral triangle of 8 cm. Tall. 73 - "DUAL MULTITRIAKGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY" according to claims 13 and 23, characterized in that the multipangular element is formed by three triangles and is mounted parallel to the ground plane in a patch type antenna configuration. 83 - "DUAL MULTI-TRIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY" according to claim 71, characterized in that the main beam of the antenna is oriented in the direction perpendicular to the ground plane and has the sectorial form in the horizontal plane with a width of beam at 3 dB around 652 in the GSM and DCS bands. 9§ - "DUAL MULTITRIANGULAR ANTENNAS FOR GSM AND DCS CELL PHONE" according to claim 83, characterized in that the antenna is mounted vertically with the ground plane fixed to a wall, tower or vertical pole to give sectorial coverage to a cell of the GSM and DCS cellular telephone systems. 103 - "DUAL MULTI RIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY" according to the 73 and 83 claims characterized in that the external perimeter of the triangular element is an equilateral triangle of 14 cm. of height and that the greater of the three triangles that constitute the structure is in turn an equilateral triangle of 11 cm. Tall. 113 - "DUAL MULTI-TRIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY" according to 7§ and 83, characterized in that the connection to the antenna is made in two different points for GSM and Des, . - presenting the antenna with an independent connector for each band. 12i - "DUAL MULTITRIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY" according to the 13 and 23 claims characterized in that the antenna can be reconfigured with one or two connectors (one for each one of the GSM and DCS bands) through a network standard dipiexora. 133 - "DUAL MULTI RIANGULAR ANTENNAS FOR GSM AND DCS CELLULAR TELEPHONY" according to the 6th and 10th claims, characterized in that the dimensions and the triangles are readjusted by up to 105-20% in case the conductor multitrigger element is printed on dielectric substrate whose refractive index is greater than unity. 143 - "DUAL MULTITRIANGULAR ANTENNAS FOR CELLULAR TELEPHONY GSM AND DCS "according to the 13 and 23 claims characterized in that the total size of the antenna can be reduced by loading the multitriangular element with an inductive loop 15§ -" DUAL MULTITRIANGULAR2S ANTENNAS FOR CELLULAR TELEPHONY GSK AND DCS "according to the 13 and 23 characterized claims in which the impedance in the first band can be adjusted by cutting the triangular tip of the vertex closest to the power supply point.