FR2950488A1 - Electronic device for receiving female coaxial connector of e.g. digital, cellular trunked radio system in vehicle application, has core whose part projects with respect to opening such that part is in electrical contact with contactor - Google Patents

Abstract

The device (1) has a case (2) including a circular opening (3) to receive a female coaxial connector (6) that receives a male coaxial connector (13). A conductive core (7) traverses the female coaxial connector. An electronic global positioning system signal processing circuit (4) is arranged in the case. A contactor element (5) i.e. flexible contactor, is fixed on the electronic circuit. The conductive core has a projecting part (7A) that projects with respect to the opening such that the projecting part is in electrical contact with the contactor element.

Description

ELECTRONIC DEVICE

The invention relates to an electronic device. The electronic device according to the invention finds a particular application in the field of radiocommunication terminals. The invention applies more advantageously to professional mobile radio terminals (or PMR terminals of the "Professional Mobile Radio" type) of the TETRA ("Trans European Trunked Radio") type or TETRAPOL defined by the industrials forum. TETRAPOL (http://www.tetrapol.com) equipped with a Global Positioning System (GPS) and / or Galileo. A PMR radio terminal usually comprises a housing including a lower receptacle and an upper cover capable of being assembled. An electronic card including a plurality of electronic circuits, including an electronic circuit PMR, is positioned in the lower receptacle of the housing. The lower receptacle further comprises a female coaxial connector adapted to receive a male coaxial connector connected to a remote antenna and a connection system between the PMR electronic circuit and the female coaxial connector.

The connection system comprises a coaxial connection plug fixed on the electronic circuit PMR and a coaxial cable having, at one of its ends, a coaxial connection plug coming to connect to the coaxial connection plug fixed on the electronic circuit. At its opposite end, the coaxial cable is connected to the female coaxial connector.

The female coaxial connector of such a PMR radiocommunication terminal is connected via a male coaxial cable to a remote passive antenna, said male coaxial cable being able to transmit a radio signal from the remote passive antenna to the female coaxial connector and then from last to the electronic circuit PMR via the connection system.

When it is desired to equip the PMR radiocommunication terminal with a GPS module, it is necessary to add a GPS electronic circuit on the electronic board and a female coaxial connector on the housing, the female coaxial connector being able to receive a connector. coaxial male and a connection system between the GPS electronic circuit and the female coaxial connector. The female coaxial connector and the connection system may be substantially identical to those previously described with reference to the electronic circuit PMR. Such a connection system is all the more essential to integrate in a radiocommunication terminal equipped with a GPS module operating at high frequencies. In this case, the connection system comprises a coaxial connection plug fixed on the GPS electronic circuit and a coaxial cable having at one of its ends, a coaxial connection plug coming to connect to the coaxial connection plug fixed on the electronic circuit. GPS. At its opposite end, the coaxial cable is connected to the female coaxial connector. The female coaxial connector is connected via a male coaxial cable to a remote active or passive GPS antenna, said male coaxial cable being able to transmit a GPS signal from the active or passive antenna remote to the female coaxial connector and then from the latter to the GPS electronic circuit via the connection system. In the case of the remote active antenna, the male coaxial cable is also used to power the remote antenna via a power supply integrated in the GPS or PMR electronic circuit (ie the core of the male coaxial cable transmits a data signal from the antenna active remote to the box and a DC power supply from the box to the remote active antenna). When assembling the GPS electronic circuit in the housing, an operator must assemble the coaxial connection plug of the coaxial cable with the coaxial connector plug of the GPS electronic circuit.

Such a configuration, however, has a number of disadvantages, which must be taken into account from the design of the housing. When designing the housing, a sufficient length, position and radii of curvature of the connection system must be taken into account in order to avoid forces generated on the one hand by the coaxial plug for connecting the coaxial cable to the coaxial plug connection connected to the electronic circuit (risk of tearing) and secondly, by the coaxial plug fixed on the electronic circuit on the coaxial cable (risk of opening in the ground braid).

It is also necessary to take into account a length, a position and sufficient radii of curvature of the connection system from the design of the housing to allow the assembly of the lower receptacle with the upper cover. It is also necessary to provide cutouts in the electronic circuit, depending on the position of the female coaxial connector in the lower receptacle of the housing. Despite these precautions during the design of the case, assembly by the operator remains a delicate operation, random and not guaranteed. Indeed, during the assembly of the two coaxial connection plugs, the operator assigns a position and therefore radii of curvature to the coaxial cable so that the latter does not prevent the assembly of the receptacle with the lid of the housing. Another disadvantage lies in the fact that the radius of curvature attributed to the coaxial cable of the connection system can cause an unsuitable positioning of the coaxial plug for connecting the coaxial cable with respect to the positioning of the coaxial connection plug fixed on the electronic circuit. GPS. Such a non-adapted positioning is likely to generate a force on the coaxial connection plug fixed on the GPS electronic circuit. This effort can eventually lead to tearing of the coaxial connection plug fixed on the GPS electronic circuit. Such tearing has the effect of removing the connection between the female coaxial connector and the GPS electronic circuit. The force can also cause poor contact between the two coaxial connection plugs generating spurious effects.

Moreover, a PMR radiocommunication terminal as described above comprising two female coaxial connectors therefore implies the use of two coaxial connection systems and therefore of two coaxial cables with a coaxial connection plug at their end. Therefore, the presence of two coaxial cables is likely to cause increased assembly constraints. Indeed, the operator must accurately position the two coaxial cables so as to avoid any overlap that could generate spurious effects.

Finally, the coaxial connection systems as described above have a significant cost. In this context, the invention aims at providing an electronic device incorporating a female coaxial connector and an electronic circuit, said device ensuring the electrical contact between said female coaxial connector and said electronic circuit simply, economically and efficiently, having constraints of Restricted assembly, limiting the spurious effects of a non-coaxial connection or an overlap of coaxial cables and allowing the integration of one or more coaxial connectors, for example for the arrival of PMR and / or GPS signals. To this end, the invention relates to an electronic device comprising: a housing, said housing having an opening adapted to receive a female coaxial connector, said female coaxial connector being adapted to receive a male coaxial connector, said female coaxial connector comprising a conductive soul crossing it; an electronic circuit disposed in said box; a contactor element fixed on said electronic circuit; said electronic device being characterized in that said conductive core of said female coaxial connector has a protruding portion with respect to said aperture such that said projecting portion is in electrical contact with said contactor element. Thanks to the invention, assembly constraints are minimal or nonexistent. A contactor element of the flexible contactor element type is used, so when the portion projecting from the opening of the housing bears on the flexible contactor element, the latter flexes and ensures electrical contact with the protruding part. Therefore, if the female coaxial connector is disposed in the housing cover and the electronic circuit is located in the receptacle of the housing, when the cover and the receptacle are joined, the projecting portion comes into contact with the contactor element. fixed on the electronic circuit. In other words, no action is taken to make the electrical contact. In addition, compared to the devices of the prior art, the number of part is decreased as well as the associated cost.

In addition to the main features which have just been mentioned in the preceding paragraph, the electronic device according to the invention may have one or more additional characteristics below, taken individually or in any technically possible combination: said contactor element is a contactor flexible ; said contacting element comprises a first part able to be fixed on said electronic circuit and a second flexible part able to flex when a force is applied to it so that an electrical contact is made between said projecting part and said second part. part of said contact member when said protruding portion exerts a force on said second portion; said electronic circuit comprises a filter comprising a first path of the high-pass filter type capable of passing high-frequency signals flowing from said female coaxial connector to said electronic circuit; said filter comprises a second channel of the low-pass filter type capable of passing a continuous electric current flowing from said electronic circuit to said female coaxial connector; said first channel and said second channel are respectively a high-pass filter and a low-pass filter connected in parallel so that the response of the filter formed by the combination of these two channels has a peak of rejection at a determined frequency, for example at the PMR frequency, to avoid problems of self-disturbance; said first channel and said second channel are able to compensate for a power loss of said high frequency signals induced by an assembly consisting of said protruding part of said female coaxial connector in electrical contact with said contacting element. The input elements of the filter are tuned to the parasitic elements to obtain a resonance, for example at the GPS frequency; said female coaxial connector is able to receive GPS signals, said electronic device according to the invention comprising a second female coaxial connector able to receive signals at PMR frequencies. Other characteristics and advantages of the invention will emerge clearly from the description which is given hereinafter, by way of indication and in no way limitative, with reference to the attached appended figures among which: FIG. 1 represents, schematically, a sectional view of an electronic device according to a first embodiment of the invention connected to an antenna via a coaxial cable; FIG. 2 schematically represents a sectional view of an electronic device according to a second embodiment of the invention; FIG. 3 schematically represents a sectional view of an electronic device according to a third embodiment of the invention; FIG. 4 represents an example of a filter that may comprise an electronic device as represented in FIGS. 1 to 3; FIG. 5 represents a Bode diagram illustrating the role of the filter as represented in FIG. 4.

For the sake of clarity, only the elements useful for understanding the invention have been shown, and this without regard to the scale and in a schematic manner. Similarly, the same elements include similar references in different figures. FIG. 1 illustrates an example of an electronic device 1 according to the invention. The electronic device 1 according to the invention can be formed, for example, by a radio communication terminal of TETRAPOL type operating at a PMR frequency of the order of 80 MHz and further comprising a GPS module. More particularly, FIG. 1 shows in sectional view the GPS part of an electronic device 1 according to the invention connected to a remote active antenna 16 via a coaxial cable 10 comprising at one of its ends a male coaxial connector 13. A the opposite end, the coaxial cable 10 is connected by any means whatsoever, to the remote active antenna 16. The device 1 comprises: - a housing 2 formed by a lower part (denoted indifferently by the term receptacle) 11 and an upper part (designated indifferently by the term cover) 12, the housing 2 having a substantially circular opening 3; an electronic circuit 4 made on a Printed Circuit Board (PCB) - a contactor element 5 comprising a first part 5A and a second part 5B; - A female coaxial connector 6. The female coaxial connector 6 comprises: - a conductive core 7 having a projecting portion 7A inside the housing 2 from the opening 3; - A holding body 8, for example platinum, ensuring the mass contact on the housing 2; an insulating protection 9 partially surrounding the conductive core 7 on a portion 7B of its length; - A receptacle 15. The portion 7A comprises a portion 7D surrounded by the insulating protection 9 (the portion 7D corresponds to the portion of the portion 7B projecting inside the housing 2 from the opening 3) extended by a portion 7C stripped.

The male coaxial connector 13 comprises a plug 14 adapted to be inserted into the receptacle 15 so as to make an electrical contact between the coaxial cable 10 and the conductive core 7 of the female coaxial connector 6. The printed circuit board may comprise a plurality of electronic circuits including an electronic circuit PMR signal processing (not shown) and an electronic circuit 4 GPS signal processing (shown in sectional view). FIG. 1 illustrates, more particularly, the GPS part of the electronic device 1 according to the invention.

The electronic circuit 4 is positioned within the receptacle 11 below the opening 3. The first part 5A of the contactor element 5 is for example welded to the upper face of the electronic circuit 4. It should be noted that the second part 5B of the contactor element 5 is particularly advantageously flexible. The female coaxial connector 6 is mounted on the cover 12. More specifically, the female coaxial connector 6 is positioned in the second part of the opening 3 that the cover 12 comprises. The holding body 8 is then assembled by screwing by means of two screws (not shown) on the cover 12. The receptacle 11 and the cover 12 can be assembled by means of screws, clips or any other means of assembly. When the receptacle 11 and the cover 12 are assembled, an electrical connection is made via the second portion 5B of the contactor element 5 between the electronic circuit 4 and the protruding part 7A (part of the conductive core 7 going beyond of the opening 3) of the conductive core 7. More precisely, it is the bare end 7C of the projecting portion 7A which bears on the second part 5B of the contactor element 5. As the second part 5B is flexible, the latter bends under the force exerted by the projecting portion 7A and is supported on the uninsulated portion 7C of the portion 7A providing electrical contact. It should be noted that unlike the device of the state of the art, during the assembly of the housing 2 no action is performed by an operator for the contacting of the female coaxial connector 6 with the electronic circuit 4, this bringing into contact automatically when the operator closes the housing 2 by joining the cover 12 to the receptacle 11. Moreover, the length of the conductive core 7 of the female coaxial connector 6 is chosen according to the distance of the contacting element 5 with the holding body 8 (or opening 3) of the female coaxial connector 6. In other words, the more the contacting element 5 is moved away from the holding body 8 (or the opening 3), the longer the projecting portion 7A of the conductive core 7 is extended so as to be able to make a connection between the latter and the contactor element 5. The conductive core 7 may be formed by a strand or a plurality of twisted strands. The material of this strand (s) may be copper or gold. When the strand (s) is (are) not gold, a thin layer of gold may cover the strand (s). The insulating protection 9 is made of a dielectric material so as to avoid any contact with another element that can generate electrical interactions of short-circuit type.

Moreover, the female coaxial connector 6 and the contactor element 5 are capable of passing GPS signals from the active remote antenna 16 to the electronic circuit 4 and are able to supply the remote active antenna 16 electrically with an electric current. flowing from the electronic circuit 4 to the remote active antenna 16. The intensity of the DC electric current can typically be of the order of 50 mA for an applied voltage of between 3 and 5V. FIG. 2 represents a sectional view of an electronic device 1 according to a second embodiment of the invention. As a comparison with FIG. 1, the electronic circuit 4 and the female coaxial connector 6 are situated on the same part of the casing 2, such as, for example, the receptacle 11 having an opening 3 (the cover 12 of the FIG. not present here and does not contribute to the realization of the opening 3 directly integrated in the receptacle 11). The female coaxial connector 6 is positioned above the electronic circuit 4. Apart from this difference, the various elements making up the electronic device 1 are similar. What differentiates the electronic device 1 shown in Figure 1 from that shown in Figure 2 are essentially assembly steps. In a first step, the electronic circuit 4 comprising the contacting element 5 is positioned within the receptacle 11, and then, in a second step, the female coaxial connector 6 is introduced into the opening 3 that the receptacle 11 comprises. female coaxial 6 is introduced into the opening 3, the uninsulated portion 7C of the projecting portion 7A of the conductive core 7 exerts a force on the second part 5B (ie the flexible part) of the contacting element 5, which bends under this force and is positioned below the protruding portion 7A of the conductive core 7. A contact is thus made between the contacting element 5 and the conductive core 7.

FIG. 3 represents a sectional view of a device 1 according to the invention according to a third embodiment. In such an implementation: the female coaxial connector 6 is positioned in the opening 3 that includes the receptacle 11, the latter being positioned below the electronic circuit 4; the contactor element 5 is fixed on the underside of the electronic circuit 4. Thus, when the electronic card 4 is positioned within the receptacle 11, an electrical connection is made via the contacting element 5 between the electronic circuit 4 and the part in is 7A. Indeed, the second portion 5B of the contactor element 5 bears on the non-insulated protruding portion 7A. In general, it should be noted that the electronic device according to the invention may comprise a plurality of coaxial connectors provided with conductive cores adapted to make contact with a plurality of contact elements that comprises a plurality of respective electronic circuits. In addition, the electronic device can integrate connections such as those implemented by the invention and connections implemented by the devices of the prior art. Take for example an electronic device 1 comprising in particular a 4 GPS electronic circuit and an electronic circuit PMR. The electronic circuit 4 GPS can be connected to a female coaxial connector 6 by means of the contactor element 5. The electronic circuit PMR can be connected to a female coaxial connector by means of a connection system in accordance with those used in TETRAPOL devices of the prior art. For example, a coaxial connection plug is fixed on the electronic circuit PMR and a coaxial cable having, at one of its ends, a coaxial connection plug is connected to the coaxial connection plug fixed on the electronic circuit PMR. At its opposite end, the coaxial cable of the connection system is connected to the conductive core of the female coaxial connector.

FIG. 4 illustrates a filter 40 that may comprise an electronic device 1 according to the invention. The electronic device 1 comprises a first female coaxial connector used for receiving GPS signals and a second female coaxial connector used for receiving PMR signals having for example a frequency of the order of 80 MHz.

Note that the filter 40 is preferably integrated in the electronic circuit 4. The filter 40 includes a first channel 41 formed by a high pass type filter and a second channel 42 formed by a low pass type filter. The first channel 41 is traversed by a GPS signal (GPS data) flowing from the remote active antenna 16 via the female coaxial connector 6 to the electronic circuit 4. The role of the first channel 41 is notably to let the high frequencies pass. forming the GPS signal. The first channel 41 also filters the direct electric current and the low frequency signals.

The second channel 42 is formed by a low-pass filter and is traversed by a continuous electric current flowing from the electronic circuit 4 via the female coaxial connector 6 to the remote active antenna 16. Moreover, it should be noted that the impedance It is controlled along the coaxial cable 10. On the other hand, a mass break is present at the projecting portion 7A and the contactor element 5. This break in mass causes a perturbation of the GPS signal related to the inhomogeneity of the propagation of the GPS signal between the female coaxial connector 6 and the filter 40. In other words, the projecting portion 7A of the female coaxial connector 6 creates a parasitic inductance and the contactor element 5 creates a parasitic capacitance having the same effects a filter passes low. Thus, the first channel 41 and the second channel 42 are adapted to compensate for the loss of impedance matching generated by the contactor element 5.

In addition, the first channel 41 and the second channel 42 of the filter 40 are adapted to filter specific frequencies. By way of example, when the electronic device 1 according to the invention comprises a GPS electronic circuit 4 and an electronic circuit PMR (receiving frequencies of the order of 80 MHz for example), the PMR frequencies can parasitize the GPS signal. . As a result, the filter 40 is adapted to filter specific frequencies (in our 80 MHz example). According to such an implementation, the first channel 41 may for example comprise: a first electrical connection 43; a second electrical connection 44; two capacitors Cl; an inductor L1; a mass M.

The first electrical connection 43 comprises the two capacitors C1 connected in series and each having a value of 4.7 pF. The two capacitors C1 are separated from each other by an electrical node N1 connecting the first electrical connection 43 to one end of the second electrical connection 44. The opposite end of this second electrical connection 43 is connected to the ground M The second electrical connection 43 comprises an inductance L1 (formed by two inductors connected in parallel, not shown, of a value each of 6.8 mH). According to such an implementation, the second path 42 may for example comprise: a first electrical connection 45; a second electrical connection 46; two inductors L2; a capacitor C2; a mass M.

The first electrical connection 45 comprises the two inductors L2 connected in series and each having a value of 6.8 mH. The two inductances L2 are separated from each other by an electrical node N2 connecting the first electrical connection 45 to one end of the second electrical connection 46. The opposite end of this second electrical connection 46 is connected to the ground M The second electrical connection 46 comprises the capacitor C2 with a value of 2.2 nF.

It should be noted that the values of the components of the filter 40 are given for illustrative purposes and are of course not limiting. FIG. 5 represents a Bode diagram 50 illustrating: the loss of power of the GPS signal that can be generated by the parasitic capacitance of the contactor element 5; compensation of the loss of power of the GPS signal by means of the filter 40 of FIG. 4; the filtering of a PMR frequency of the order, for example, of 80 MHz being able to parasitize the GPS signal. Curve 51 represents schematically and for illustrative purposes, the power loss of the GPS signal generated by a device 1 according to the invention does not include a filter 40. It can be seen that the loss of power of the GPS signal is around 11 dB between 1 GHz and 2 GHz. Curve 52 represents schematically and for illustrative purposes, the compensation of this loss of power (11 dB) by an electronic device 1 according to the invention comprising a filter 40. In addition, the curve 52 has a rejection peak 53 This rejection peak 53 is generated at the frequency of 80 MHz corresponding to a PMR frequency. This rejection peak makes it possible to suppress a PMR frequency capable of disturbing the GPS signal received by the electronic circuit 4. This rejection peak 53 is obtained by the presence of the two high-pass filters 41 and the low-pass filter 42. In general, the filter 40 makes it possible to suppress a determined frequency that can generate parasitic effects on the GPS signal. Note that the PMR operating frequency of 80 MHz is given for illustrative purposes only. Thus, some radiocommunication terminals can operate at a PMR frequency of the order of 400 MHz. In such an implementation, the filter 40 will be adapted so as to filter the PMR frequency of the order of 400 MHz.

The invention has been more particularly described for an application to a radiocommunication terminal comprising a GPS module. However, it may also be desirable to apply the electronic device in the case of any type of electronic device requiring a connection between two electrical elements. The electronic device according to the invention can be applied for remote active antennas and also for remote passive antennas. The electronic device according to the invention can be applied in the fields of automotive, naval, aviation or railway. It is understood that the skilled person is able to realize different variants of the electronic device according to the invention and in particular as regards the type of filter used as well as the elements such as inductors and capacitors the component without however, to leave the framework of the patent.

Claims (8)

REVENDICATIONS1. Electronic device (1) comprising: a housing (2), said housing (2) having an opening (3) adapted to receive a female coaxial connector (6), said female coaxial connector (6) being able to receive a coaxial connector male (13), said female coaxial connector (6) having a conductive core (7) passing therethrough; an electronic circuit (4) disposed in said housing (2); - a contactor element (5) fixed on said electronic circuit (4); said electronic device (1) being characterized in that said conductive core (7) of said female coaxial connector (6) has a projecting portion (7A) with respect to said opening (3) so that said protruding portion (7A) ) is in electrical contact with said contacting element (5). 2. Electronic device (1) according to the preceding claim characterized in that said contacting element (5) is a flexible contactor. 3. Electronic device (1) according to one of claims 1 or 2 characterized in that said contacting element (5) comprises a first portion (5A) adapted to be fixed on said electronic circuit (4) and a second part ( 5B) flexible able to flex when a force is applied to it so that electrical contact is made between said protruding portion (7A) and said second portion (5B) of said contact member (5) when said projecting portion (7A) exerts a force on said second portion (5B). 4. Electronic device (1) according to one of the preceding claims characterized in that said electronic circuit (4) comprises a filter 10 (40) having a first channel (41) of the high-pass filter type able to pass signals high frequencies flowing from said female coaxial connector (6) to said electronic circuit (4). 5. Electronic device (1) according to claim 4 characterized in that said filter (40) comprises a second path (42) of the low-pass filter type capable of passing a continuous electric current flowing from said electronic circuit (4) to said female coaxial connector (6). 6. Electronic device (1) according to claims 4 and 5 characterized in that said first channel (41) and said second channel (42) are respectively a high-pass filter and a low-pass filter connected in parallel so that the The response of the filter formed by the combination of these two channels has a rejection peak (53) at a determined frequency. 7. Electronic device (1) according to one of claims 5 or 6 characterized in that said first channel (41) and said second channel (42) are able to compensate for a loss of power of said high frequency signals induced by said part. protruding (7A) from said female coaxial connector (6) in electrical contact with said contact member (5). 8. Electronic device (1) according to one of the preceding claims characterized in that said female coaxial connector (6) is adapted to receive GPS signals, said electronic device (1) having a second female coaxial connector (6) adapted to receive signals at PMR.30 frequencies