Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/27—Adaptation for use in or on movable bodies
  • H01Q1/273—Adaptation for carrying or wearing by persons or animals
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q7/00—Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
  • H01Q7/06—Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop with core of ferromagnetic material
  • H01Q7/08—Ferrite rod or like elongated core

Definitions

• the invention relates to a transceiver antenna system.
• omnidirectional multipolarization with diagram of substantially circular radiation usable on portable transceivers or simple receivers, used in paging.
• paging systems such as the RDS system for " Radio Data System " in Anglo-Saxon language
• digital data for managing or using this network are broadcast on the carrier wave of a modulation broadcasting signal. frequency of band II.
• the data disseminated can be very diverse in nature and are generally disseminated in the form of messages intended for subscribers.
• Paging is today a means of communication widely used by a category of users called to move often, using various means of transport, in geographic environments very varied.
• the receiver In general, the receiver, or even the transceiver, is intended to be worn by its user, either inside a jacket pocket or, for example, hung on his belt. The user is unaware and has no concern whatsoever of whether the receiver, or the transceiver, is correctly oriented towards the transmitter which is broadcasting the messages.
• receivers or transceivers are very compact and normally equipped with an integrated antenna which determines their dimensional characteristics. This antenna, generally sensitive to the magnetic component of the carrier electromagnetic wave, component H, is most often formed by a very selective and gain-optimized metal frame, which gives the antenna thus formed a radiation pattern of unidirectional type, with good directivity.
• Wave polarization emitted by the installations of broadcasters, or radiotelephony is usually either horizontal or vertical, very rarely circular or oblique.
• this type of antenna does not have, in because of its one-way radiation pattern, an ability to receive, or transmit, signals radio in all azimuth directions, this which normally also imposes an orientation on the user its receiver, or its transceiver, in the horizontal plane.
• this type of antenna does it have a unidirectional radiation in two orthogonal planes, the antennas then being placed so that one of the planes either the horizontal plane, the other plane, vertical, in front correspond to the plane of polarization of the electromagnetic wave broadcast, which of course involves two orientations for optimal reception.
• the object of the present invention is to remedy the aforementioned drawbacks, by the implementation of a system omnidirectional diagram transmit-receive antennas of substantially circular radiation for which the contingencies relating to the orientation of the antenna system for optimal reception or transmission-reception are substantially removed.
• Another object of the present invention is, in particular, the implementation of an antenna system transmission-reception with a radiation diagram substantially circular in one plane, the horizontal plane.
• Another object of the present invention is, in in addition, the implementation of a transceiver antenna system with a unidirectional radiation pattern in two other planes, the three planes being orthogonal each to each.
• the omnidirectional transmit-receive antenna system with a substantially circular radiation pattern, object of the present invention is remarkable in that that it includes a first unidirectional radio antenna in a first direction defined by two orthogonal planes, forming main planes of this antenna, one of the planes defining a foreground, and a second unidirectional radio antenna by relation to a second direction defined by two planes orthogonal, forming main planes of this antenna, one plans defining a second plan.
• the first and the second antenna are placed so that the first and the second plane being orthogonal, the first and the second direction are orthogonal.
• the antenna system as well formed has a bidirectional radiation pattern in a third plane, orthogonal to the first and second plane and formed by a main plane of the first respectively second antenna, and a radiation diagram unidirectional in the first respectively the second plan.
• the first and second radio antenna each deliver a first respectively a second radio reception signal.
• a coupling circuit of the first and second antenna ensures the amplitude and / or phase combination of the first and the second reception signal, to generate a signal resulting reception including the radiation pattern corresponding to the transceiver antenna system is substantially circular in the third plane.
• the antenna system object of the present invention, finds application to paging and so more general, radiocommunication or radiotelephony mobile.
• the antenna system object of the present invention, presents a first radio antenna, noted 1, unidirectional in a first direction, this direction, denoted OX in FIG. 2a, being defined by two orthogonal planes, the OX, OZ planes respectively OX, OY.
• the above-mentioned planes form main planes of this antenna 1, one of the planes, the OX, OZ plane defining a first plane, noted C in Figure 2a.
• the antenna system, object of the present invention also has a second radio antenna unidirectional, denoted 2, in a second direction, the direction OY in FIG. 2b, this direction being defined by two orthogonal planes, OX, OY, respectively OY, OZ. These two planes form the main planes of the antenna 2, one of the planes, the OY, OZ plan defining a second plan, noted B in Figure 2b.
• the first 1 and the second antenna 2 are placed in the vicinity of each other of so that the first C and the second plane B are orthogonal, the first and second direction OX, respectively OY are also orthogonal.
• a radiation pattern substantially omnidirectional formed by a diagram of bidirectional radiation in a third plane A, such as shown in Figure 2c.
• Plan A is orthogonal to first and second plane and is formed by a plane principal of the first respectively of the second antenna 1.2.
• the radiation pattern significantly omnidirectional antenna system thus formed includes also a one-way radiation pattern in the first C respectively in the second B plane, as well as shown in Figures 2e and 2d.
• the first and the second radio antenna each deliver a first e1 respectively a second e2 radio signal reception.
• a coupling circuit 3 ensures the amplitude and / or phase combination of the first e1 and the second e2 reception signal to generate a signal resulting reception and including the radiation diagram, for the corresponding transceiver antenna system, is substantially circular in the third plane A.
• the antenna system object of the present invention, can be used both at the reception than on transmission, due to the dual nature of the radiation pattern in reception, respectively in emission, these radiation patterns being, in accordance to the classical theory of antennas, identical to the emission and at the reception.
• the paging function is not necessary, it can then be deleted.
• the first antenna 1 is a metal frame antenna surrounding the actual body of the R receptor and the second antenna 2 is a core antenna ferrite.
• the metal frame antenna 1 surrounds for example the circuits of the receiver R, as shown in the Figure 3a, and is housed in the housing, not shown, of the receiving device, which of course includes a P battery for electric power supply.
• the second antenna 2 also includes a frame metallic 20 with which is further associated a core of ferrite 21.
• the second ferrite core antenna is placed near one of the sides of the metal frame constituting the first antenna 1 for example.
• the configuration thus produced of course allows, for a given position of the receiver in space, receive in all azimuthal positions, i.e. for any orientation of the receiver in plane A, a suitable signal level due to orthogonal arrangement polar radiation patterns relating to each of the antennas, as shown in Figure 2c.
• the tuning of each antenna on the frequency of the wave incident carrier can be achieved through variable capacity diodes, not shown in the drawing.
• FIG 3b there is shown, for the mode of realization of figure 3a, the orthogonal induction flows received by the first 1 and the second antenna 2 in OX and OY directions.
• the plane B is the plane of the sheet containing Figure 3b
• plane A is a plane horizontal orthogonal to the plane of the sheet containing the Figure 3b
• the plane C is a vertical plane orthogonal to plan of the sheet containing Figure 3b.
• the OXYZ benchmark respectively O'X'Y'Z 'corresponds to the oxyz coordinate system of Figures 2a to 2e.
• Figures 4a, 4b and 4c there is shown the polar patterns of respective radiation received by the first and second antenna in the directions OX and OY.
• the antenna system object of the present invention, offers the possibility of quasi-omnidirectional reception in the horizontal plane A thanks to the coupling circuit 3, which allows, thanks to a electronic system which will be described below in conjunction with Figures 5a, 5b and following, to perform a amplitude and / or phase combination of the first e1 and the second e2 reception signal.
• FIG. 5a a system has been represented.
• transmission-reception antennas in accordance with the subject of the present invention composed of two tuned antennas separately and perpendicular to each other, the first 1 respectively second antenna 2 such as shown previously in Figure 3b for example.
• the first and second antenna 1, 2 are tuned to the same frequency, that of the wave incident carrier, under conditions as described earlier in the description.
• the first 1 and the second antenna 2 are assumed to be subjected to an electromagnetic field of magnetic component vertically polarized, as shown in Figure 5a.
• the amplitudes of the first e1 respectively of the second e2 radio reception signal are established in the following manner.
• the vector represents the magnetic component of the electromagnetic field of amplitude B1, and represent the oriented surfaces of the first respectively second antenna 1,2 with respect to the wave vector of the incident wave, S1 and S2 representing the value of the surfaces of the first respectively second antenna 1.2.
• ⁇ o represents the permeability of the vacuum
• ⁇ r the relative permeability of the magnetic material constituting the nucleus of the second antenna 2
• ⁇ the term of pulses of the incident carrier wave
• t time the term of pulses of the incident carrier wave
• this consists in introducing, on the radio signals reception e1 and e2, a phase shift term relative ⁇ to compensate for the introduced directivity term by the inclination of the angle ⁇ of the direction of polarization of the incident electromagnetic wave by relative to the orientation of the antenna system.
• the aforementioned directivity term can be rendered independent of ⁇ , i.e. the orientation angle of the antenna system with respect to the polarization direction of the incident carrier wave.
• the coupling circuit 3 may include a circuit 30 of relative phase shift of the first and second radio signals of reception e1, e2 of a phase shift value determined, this circuit 30 making it possible to generate a first e1 ⁇ and a second e2 ⁇ phase shifted reception signal.
• ⁇ denotes the relative phase shift introduced between the first e1 and the second e2 radio reception signal.
• the coupling circuit 3 includes a summing circuit 31 first and second phase shift reception signals e1 ⁇ , e2 ⁇ , this summing circuit making it possible to generate the signal resulting reception er, which of course checks the relation (6) previously mentioned.
• the resulting reception radio signal er is a signal corresponding to a transceiver antenna system whose radiation pattern is substantially circular in the third plane A previously described in the description.
• the relative phase shift circuit 30 can advantageously be formed by a controlled phase shifting circuit 30a receiving on a relative phase shift control input a phase shift control signal, noted c ⁇ , proportional to ratio of the amplitude of the second and the first signal radio reception.
• the signal c ⁇ can be realized from an analog type circuit, or from a circuit type transcoding value 30b, which, from the signals radio reception e1 and e2, after amplification, delivers the proportional phase shift control signal for example to the ratio of the amplitude of the second and of the first radio reception signal e1, e2.
• the embodiment as shown in figure 6b thus makes it possible to control the relative phase shift between the first e1 and the second reception signal e2 to the value the orientation angle of the antenna system with respect to to the direction of polarization of the incident wave and thus to generate a reception signal resulting er whose the circular reception diagram in the third plane A is independent of this orientation angle and of the geometry relative of the first and second antenna.
• the antenna system can be used regardless of orientation of the antenna system with respect to the direction of polarization of the incident wave, the amplitude term being able be made maximum and independent of the directivity term for maximum antenna gain, i.e. for maximum reception amplitude.
• the transceiver antenna system, subject of the present invention can, if necessary, be used in circular polarization of the incident carrier wave.
• phase shift circuits 30 or 30a can be produced by phase shift circuits of the trade, marketed under the reference PSCQ 2-120 by the MINICIRCUIT company in France.
• phase shifters are passive phase shifters with a reversible character, that is to say bi-directional transmission.
• the realization of a reversible summing circuit of magic tee type for example, for the constitution of the summing circuit 31, of course allows the use of the omnidirectional antenna system both on emission and on reception, allowing applications to be considered very varied.
• omnidirectional radiation diagram substantially circular, particularly efficient.
• this allows in permanence of obtaining an omnidirectional reception of messages transmitted by systems such as the system R.D.S. for example.

Landscapes

• Variable-Direction Aerials And Aerial Arrays (AREA)
• Radio Transmission System (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=9466813

Family Applications (1)

Country Status (4)

Cited By (1)

Citations (8)

• 1994
  • 1994-09-09 FR FR9410800A patent/FR2724492B1/fr not_active Expired - Fee Related
• 1995
  • 1995-09-06 EP EP95402018A patent/EP0701297A1/fr not_active Withdrawn
  • 1995-09-08 FI FI954203A patent/FI954203A/sv unknown
  • 1995-09-11 JP JP7233120A patent/JPH08181642A/ja not_active Withdrawn

Patent Citations (8)

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