DESCRIPTION

Field of application

The present invention relates to a flexible antenna for NFC communication with a SIM card of a mobile device.

More particularly, the invention relates to a flexible antenna including an RF pad for establishing a radio communication between the SIM card of the mobile phone and another device, in the radio frequency range of the flexible antenna.

Prior art

As known, near field communication (NFC) is a set of communications standards for smart phones and similar devices for establishing radio communication by touching devices or bringing them into close proximity, usually no more than a few centimeters.

NFC communications standards cover communications protocols and data exchange formats, and are based on existing radio- frequency identification (RFID) standards including ISO/IEC 14443. They are based on RFID systems, allowing two-way communication between endpoints.

For instance, NFC devices can be used in contactless payment systems, similar to those used in credit cards and electronic ticket smartcards, and allow mobile payment to replace or supplement these systems. NFC tags contain data and are typically read-only but may be rewriteable; they can be custom-encoded by their manufacturers or use the specifications provided by the NFC Forum, an industry association charged with promoting the technology and setting key standards.

The tags can securely store personal data such as debit and credit card information, loyalty program data, PINs and networking contacts, among other information.

Single Wire Protocol (SWP) is a technology by which the NFC radio interface is exposed to the SIM card. The standard specification of SWP is set forth at ETSI TS 102 613. The ETSI TS 102 613 defines various aspects of SWP standard including overall structure, data exchange, physical characteristics such as temperature range for card operation, electrical characteristics, communication stacks, and the like. The SWP interface is a bit oriented point-to-point communication protocol between a UICC (SIM) and a contactless frontend. The contactless frontend (CLF) is the master and the UICC is the slave. The communication is performed based on the transmission of digital information in full duplex mode.

In several practical applications, due to the security reason, it's advised that the contactless service, e.g. payment, is driven by SIM rather than by the handset software, even though the radio interface for the contactless service is provided by the handset software.. However, only the most advanced smart phones are provided with NFC and even less with SWP. Thus, a complementary and economical means for utilizing the NFC with SWP is requested.

Flexible antennas implement such complementary and economical means for utilizing the NFC with SWP. In fact, a non-NFC mobile phone can be upgraded to NFC by means of a flexible antenna. Figure 1A schematically shows the backside view of the flexible antennas used in a cellular phone.

Figure 1A shows a main body of phone (backside) 100 comprising a space for battery 130. The battery 1 10 is put in the space 130 and the back cover 170 covers the backside of the main body 100. The SIM card 120 is disposed on the SIM slot 140 for communicating with the main body 100. This is a normal configuration for using USIM in the phone without the support for NFC.

To use the functionality of NFC, a flexible antenna 155 may be inserted in the space for battery 130. Particularly, the flexible antenna 155 comprises SIM pad 190, flat cable 160, and CL tag RF antenna 180. At least one connection line 150 is formed on the Flat cable 160 to connect the SIM pad 190 with CL tag RF antenna 180. The flexible antenna 155 implements the SWP standard so that the SIM card utilizes NFC protocol. The flexible antenna 155 usually sells in a bundle with a pay SIM.

Figure IB schematically shows the side view of the flexible antenna used in the cellular phone of figure 1A. Referring to the side view, the flat cable 160 of the flexible antenna 155 is folded on the free side of the battery 1 10 wrapping around the SIM card 120 and the battery 1 10. The CL tag RF antenna 180 is put at the backside of the battery 1 10 and right in front of the back cover 170. The CL tag RF antenna 180 is capable of transmitting and receiving radio signal over the plane of the back cover 170. Since the flexible antenna 155 lays over the battery 1 10, the flexible antenna 155 has a better efficiency than if it were inside between the battery and the phone PCB. If the CL tag RF antenna 180 were disposed between the battery 1 10 and the main body 100 including phone PCB, the radio signal emitted from the CL tag RF antenna 180 would be affected by the electromagnetic wave generated by the phone 100 or be shielded by the battery 1 10.

The flat cable 160 may have an appropriate length so that whole portion of the flexible antenna 155 may be loaded inside of the cellular phone without generating any wrinkle on the Flat cable 160. The SIM pad 190 is aligned to the SIM card 120 and they are inserted together in the SIM slot 140. The SIM card 120 is coupled with both the SIM pad 190 and the SIM interface in the SIM slot 140. The whole portion of the flexible antenna 155 may be thin enough for the back cover 170 to fit it perfectly.

Figure 2 A and Figure2B schematically shows the battery contacts and SIM slot having different orientation.

In figure 2A, the battery contact 200 is formed at the right portion of the main body 100. The SIM slot 140 is formed at the center of the main body 100 and to the left of the main body 100. The flat cable 160, should not cover the battery contact 200. Otherwise, the battery 1 10 would not guarantee a stable voltage or the battery contact 200 would not be coupled to the battery 1 10. Similarly, the flat cable 160 should not interfere with other obstacles such as the cover handle, because the said flat cable 160 could break. For this aim, the flat cable 160 should be positioned to the left side of the SIM pad 190 as depicted in the rightmost portion of figure 2A.

On the contrary, in figure 2B, the battery contact 200 is formed at the left portion of the main body 100. The SIM slot 140 is formed at the center of the main body 100 and to the right of the main body 100. The flat cable 160 should not cover the battery contact 200. In this case, the flat cable 160, i.e. the cable, should be positioned to the right side of the SIM pad 190, as depicted in the right-side portion of figure 2B.

Due to the different position of the battery contact and the different orientation of the SIM slot, different SIM pads shape are necessary.

Figure 3 schematically shows four different shapes of the flexible antennas, with the orientation feature in different position with respect to the CL tag connections.

To support the different orientation of SIM slot and the different position of the battery contact, a number of flexible antennas should be sold as a bundle together to the consumers. In figure 3, four flexible antennas 300, 310, 320 and 330 with a SIM pad having different orientation are showed. For instance, the first flexible antenna 330 comprises a SIM pad with diagonal edge 380 oriented toward the left upper side. The second flexible antenna 320 comprises a SIM pad with diagonal edge 370 oriented toward the right down side. The third flexible antenna 310 comprises a SIM pad with diagonal edge 360 oriented toward the right upper side. The fourth flexible antenna 300 comprises a SIM pad with diagonal edge 350 oriented toward the left down side.

The consumer usually would use only one of the several flexible antennas and the other antennas become wasteful, which causes unnecessary production cost.

The technical problem at the base of the present invention is how to provide a flexible antenna for NFC communication with a SIM card of a mobile device, such antenna being adapted to the different arrangements of battery contacts inside the mobile device, as well as to different arrangement and size of the battery or the SIM slot within the mobile device, overcoming the limitation and costs that currently affects the known antennas or bundles of antennas provided for NFC communication .

Summary of invention

The technical problem mentioned above is solved by a flexible antenna for supporting NFC communication with a SIM card of a mobile device, comprising a RF pad for establishing radio communication with another device, and characterized by further comprising a plurality of projections extending from the RF pad, wherein each of the plurality of projections comprise on its end a SIM pad with a different orientation. Advantageously, according to the claimed solution, instead of producing four different and separate antennas, each having a respective RF pads and a respective SIM pad with specific orientation, only one flexible antenna is provided with one single RF pad and several projections, e.g. the cables, ending in differently oriented SIM pads, thereby reducing the production cost for RF pad. Moreover, the volume of the product package can be reduced.

RF pad may include a pattern formed by conductive material which serves as means for radio communication. That is to say, RF pad may include an antenna for transmitting and/ or receiving signals with another device.

In an aspect of the invention, to couple the flexible antenna with the mobile device, one of the projections including the SIM pad having matching orientation with a SIM slot of the mobile device is previously selected, and the other projections are removed. In this way, only the removed cables and SIM pads are wasted.

In another aspect of the invention, each of said plurality of projections comprises at least one conductive wire electrically coupling the RF pad with the SIM pad. The conductive wires are insulated from each other. Thus, the projection, i.e. the cable, includes wire or conductive line with insulated each other by a cover of the cable.

In another aspect of the invention, at least one of the projections comprises a cutting or pre-cutting line for simplifying the removal of unnecessary projections from the RF pad. The cutting line preferably has an indication line with different color from that of the projections. The consumer is thus facilitated in finding the appropriate cutting position visually. Said cutting line may include a groove formed along the direction of said cutting line. In another aspect of the invention, the RF pad has a rectangular shape, the number of projections is four, and each projection extends from each edge of the RF pad. In another aspect of the invention, the number of projections is two and each projection extends from an adjacent edge of the RF pad.

In another embodiment, each of the projections extends from opposite edge of the RF pad. Advantageously, according to the invention, the number is chosen depending on how many SIM pads with different orientation, with respect to battery contacts and other obstacles exist in the handset models spread in the customer base of the reference market. For example, the number of projections may be three and each projection may extend from an edge of the RF pad, except one. When, the RF pad has a rectangular shape, at least two of the projections may extend from an edge of the same side of the RF pad.

In another aspect of the invention, the RF pad includes a NFC controller. Due to this, the production price of RF pad could be lowered further.

Further advantages and features of the flexible antenna for NFC communication according to the present invention are apparent from the description given here below only for exemplificative purpose and without limiting the scope of protection of the present invention.

Brief description of the drawings

Figure 1A schematically shows a backside view of a flexible antenna used in a smart phone, according to the prior art.

Figure IB schematically shows a side view of a flexible antenna used in the smart phone of figure 1A, according to the prior art.

Figure 2A and Figure2B schematically shows battery contacts and a SIM slot having different orientation, according to the prior art. Figure 3 schematically shows four different shapes of the flexible antennas, according to the prior art.

Figure 4A schematically shows a flexible antenna with projections, according to the present invention.

Figure 4B schematically shows the flexible antenna with cutting position of figure 4 A.

Figure 4C schematically shows the flexible antenna with cutting line, according to the invention.

Figure 5 schematically shows the flexible antenna with two projections according to another embodiment of the invention.

Figure 6 schematically shows the flexible antenna with two different projections according to another embodiment of the invention.

Figure 7 schematically shows the flexible antenna with three projections according to a fourth embodiment of the invention.

Figure 8 schematically shows the flexible antenna with two projections extended at a same side, according to a fifth embodiment of the invention.

Detailed description

Figure 4A schematically represent a flexible antenna according to the present invention, comprising a plurality of projections.

A flexible antenna 400 according to the first embodiment supports NFC communication with SIM card in a mobile device. The flexible antenna 400 comprises a RF pad 490 establishing radio communication with another device situated in the outside of the mobile device. The RF pad 490 may exchange radio signals with the device.

The flexible antenna 400 comprises a plurality of projections, e.g. cable, extending from the RF pad 490. In figure 4A, the flexible antenna comprises a first projection 430, a second projection 431 , a third projection 432, a fourth projection 433 in each of four directions from the squared shaped RF pad 490. Each of the projections comprises on its end a SIM pad. More particularly, the first projection 430 comprises first SIM pad 410, the second projection 431 comprises second SIM pad 425, the third projection 432 comprises third SIM pad 420 and the fourth projection 433 comprises fourth SIM pad 415.

The RF pad 490 includes a pattern formed by a conductive material which serves as means for radio communication. More particularly, RF pad includes an antenna for transmitting and/ or receiving signals with another device. Due to the physical structure, the SIM card inserted in the mobile device may directly communicate with another device through the RF pad 490, SIM pad, and the corresponding projection cable.

Each SIM pad has a different orientation. For example, the first SIM pad 410 has a diagonal edge of SIM pad directing to the left-up side 450 which is opposite side from the position of the first projection 430, while the second SIM pad 425 has a diagonal edge of SIM pad directing to the left-down side 465 which is adjacent side from the position of the second projection 431. In a similar manner, the diagonal edge 460, 465 of the third SIM pad 420 and the fourth SIM pad 415 have a different angle from one another. This different configuration allows the consumers to choose one SIM pad which fits their own mobile device. The consumer may select one of the projections 430, 431, 432, 433 including SIM pad having matching orientation with a SIM slot of the consumer's mobile device; the other projections can be removed.

With reference to figure 4A, the SIM pad 410 is at a central and high position with respect to the RF pad; a long side of the SIM pad is perpendicular to the projection 430 and the diagonal edge is in the upper and left quarter of the SIM pad 450. Whether the flexible antenna is turned, for example clockwise, in this embodiment for 90°, the SIM pad 415 is placed at the central and high position with respect to the RF pad; in this case, the short side of the SIM pad 415 is perpendicular to the projection 433 and the diagonal edge is in the upper but right quarter of the SIM pad 415. Thus, not only the position of the diagonal edge of the SIM pad 415 with respect to the corresponding projection 433 changes, in comparison to the position of the diagonal edge of the SIM pad 410 with respect to his corresponding projection 430, but also the side of the SIM pad attached to the corresponding projections, i.e. the short side for SIM pad 415 and the long side for SIM pad 410.

This allows to arrange the SIM pad 415 in a mobile phone in which the distance between a SIM slot of a first mobile phone, wherein the SIM pad 415 should be placed, and the back of the battery pack of such first phone, wherein the RF pad 490 should be placed, is greater than the distance between a SIM slot of a second mobile phone, wherein the SIM pad 410 may be placed, and the back of the battery of such second phone, wherein the RF pad may 490 be placed. This arrangement also allows to couple different SIM pads 410, 415 to different shapes of SIM slots of different mobile phones.

In this same way, whether the flexible antenna is turned again, for example clockwise, for other 90°, the SIM pad 420 is placed at the central and high position with respect to the RF pad; in this case, the short side of the SIM pad 420 is perpendicular to the projection 432 but the diagonal edge is in the lower and left quarter of the SIM pad 415, i.e. the part more proximate to the projection and to its left.

Several modification in the number of SIM pads attached to the RF pad, in the length of the different projections corresponding to such SIM pads, in the arrangement of the short and long side of the SIM pads with respect to the projections, as well as the inclination degrees of the SIM pads with respect to the projection, are provided according to the invention.

Moreover a different number of SIM pads on the same edge of the RF pad may be provided. Also the shape of the RF pad may change in different configuration according to the invention, from three to n side or edges, each edge corresponding to 0, 1 or more SIM pads. The RF pad may be also of a substantially rounded shape.

Only for exemplificative purpose, with reference to the drawings, here below are given some embodiments of the flexible antenna according to the invention.

The projection may comprise at least one conductive wire electrically coupling the RF pad 490 with corresponding SIM pad. Preferably, the projection, e.g. cable, may comprise three wires, which may include Vcc line, GND line, and signal line. The conductive wires are insulated from each other.

Advantageously, according to the invention, instead of producing four different and separate antennas, one antenna having several projections cable, can be produced, thereby reducing the production cost for RF pad.

Figure 4B schematically shows the flexible antenna with cutting position according to the embodiment of the invention above described.

If the matching SIM pad is identified as the first SIM pad 410, other SIM pads should be removed from the flexible antenna 400. In this case, the projections, e.g. cable, can be cut in three positions 480, 485, 490.

Figure 4C schematically shows the flexible antenna with cutting line or pre-cutting lines according to the first embodiment of the invention.

The flexible antenna according to the invention may have at least one cutting line 401 marked on the projection as depicted in Fig. 4C. The cutting line may be on all of the projections. A cutting line 401 facilitates the removal of unnecessary projections from said RF pad 490.

Particularly, the cutting line 401 may be an indication line having different color from that of the projections. Alternatively, the cutting line may include a groove formed along the direction of the cutting line 401.

Figure 5 schematically shows the flexible antenna with two projections according to a second embodiment of the invention.

A flexible antenna 500 supports NFC communication with SIM card in a mobile device. The flexible antenna 500 comprises a RF pad 590 for establishing radio communication with another device situated in the outside of the mobile device. The RF pad 590 may exchange radio signals with the device.

The flexible antenna 500 comprises a plurality of projections, e.g. cable, extending from the RF pad 590. In figure 5, the flexible antenna comprises a first projection 501, a second projection 502 in adjacent edges of the RF pad 590. Each of the projections comprises on its end a SIM pad 500, 510. Thus, the first projection 501 comprises first a SIM pad 510 and the second projection 502 comprises a second SIM pad 500.

The RF pad 590 may include a pattern formed by a conductive material which serves as means for radio communication. Thus, the RF pad may include an antenna for transmitting and/ or receiving signals with another device. The SIM card inserted in the mobile device can directly communicate with another device through the RF pad 590, SIM pad, and the corresponding projection (cable).

Each SIM pad has a different orientation. For example, the first SIM pad 510 has a diagonal edge of SIM pad directing to the left-up side 560. Thus, the angle of the direction of the diagonal edge of the first SIM pad 510 is at 45° right from a center base line of the first projection 501.

Meanwhile, the second SIM pad 500 has a diagonal edge of SIM pad directing to the left-up side 550. The angle of the direction of the diagonal edge of the second SIM pad 500 is at 45° left from the center base line of the second projection 502. Therefore, each SIM pad has a different orientation.

This different configuration allows the consumers to choose one SIM pad which fits their own mobile device. Thus, the consumer may select one of the projections 501, 502 including SIM pad which has a matching orientation with a SIM slot of the consumer's mobile device, and then, he may remove the other projections.

The projection may comprise at least one conductive wire electrically coupling the RF pad 590 with corresponding SIM pad. Preferably, the projection, e.g. cable, may comprise three wires, which may include Vcc line, GND line and signal line. The conductive wire may be insulated from each other.

The flexible antenna according to the invention may have at least one cutting line marked on the projection. The cutting line may exist on all of the projections. A cutting line may facilitate the removal of unnecessary projections form said RF pad. Particularly, the cutting line may be an indication line having different color from that of the projections. Alternatively, the cutting line may include a groove formed along the direction of the cutting line.

Figure 6 schematically shows the flexible antenna with two projections according to the third embodiment of the invention. The flexible antenna 600 comprises a RF pad 690 establishing radio communication with another device situated outside the mobile device; the RF pad 690 may exchange radios signals with the device.

Also in this embodiment, the flexible antenna 600 comprises a plurality of projections, e.g. cable, extending from the RF pad 690. In figure 6, the flexible antenna comprises a first projection 601 and a second projection 602 at each of the opposite edges of the RF pad 690. That is to say, the first projection 601 lies in the opposite side of the second projection 602.

The RF pad 690 may include a pattern formed by a conductive material which serves as means for radio communication. Each of the projections comprises on its end a SIM pad 600, 610; the first projection 601 comprises first SIM pad 600 and the second projection 602 comprises second SIM pad 610.

Each SIM pad has a different orientation. For example, the first SIM pad 600 has a diagonal edge of SIM pad directing to the left-up side 650. Thus, the angle of the direction of the diagonal edge of the first SIM pad 600 is at 45° right from a center base line of the first projection 601 pointing to the left direction. Meanwhile, the second SIM pad 610 has a diagonal edge of SIM pad directing to the left-down side 660. The angle of the direction of the diagonal edge of the second SIM pad 610 is at 135° right from the center base line of the second projection 602 pointing to the right direction and each SIM pad has a different orientation.

In this case, the consumers may choose one SIM pad which fits their own mobile device, i.e. selecting among the two projections 601 , 602 the one including SIM pad having matching orientation with a SIM slot of the consumer's mobile device, and then, removing the other projections. Also according to this embodiment, the projection may comprise at least one conductive wire electrically coupling the RF pad 690 with corresponding SIM pad. Preferably, the projection, e.g. cable, may comprise three wires, which may include Vcc line, GND line, and signal line. The conductive wire may be insulated from each other.

The flexible antenna according to this embodiment may have at least one cutting line marked on each of the two projections facilitating the removal of unnecessary projections form said RF pad. Particularly, the cutting line may be an indication line having different color from that of the projections. Alternatively, the cutting line may include a groove formed along the direction of the cutting line.

Figure 7 schematically shows the flexible antenna 700 supporting NFC communication with SIM card in a mobile device, according to another embodiment of the invention. The flexible antenna 700 comprises a RF pad 790 establishing radio communication with another device situated in the outside of the mobile device. The flexible antenna 700 comprises a plurality of projections, e.g. cable, extending from the RF pad 790, and more particularly, a first projection 701 , a second projection 702 and a third projection 703. In the embodiment, one edge of the RF pad is empty. Each of the projections comprises on its end a SIM pad 700, 710, 720: the first projection 701 comprises first SIM pad 720, the second projection 702 comprises second SIM pad 710 and the third projection 703 comprises third SIM pad 700.

Also in this case, each SIM pad has a different orientation. The first SIM pad 720 has a diagonal edge of SIM pad directing to the left-up side 770. Thus, the angle of the direction of the diagonal edge of the first SIM pad 720 is at 45° right from the center base line of the first projection 701 pointing to the left direction. Meanwhile, the second SIM pad 710 has a diagonal edge of SIM pad directing to the left-down side 660. The angle of the direction of the diagonal edge of the second SIM pad 710 is at 135° right from a center base line of the second projection 702 pointing to the right direction.

Furthermore, the third SIM pad 700 has a diagonal edge of SIM pad directing to the left-up side 750. The angle of the direction of the diagonal edge of the third SIM pad 700 is at 45° right from the center base line of the third projection 703 pointing to the up direction. Therefore, each SIM pad has a different orientation.

Also this different configuration allows the consumers to choose one SIM pad which fits their own mobile device. The consumer may select one of said projections 701 , 702, 703 including SIM pad having matching orientation with a SIM slot of the consumer's mobile device, and then cut the other projections.

At last, figure 8 schematically shows the flexible antenna with two projections extended at the same side according to the fifth embodiment of the invention. The flexible antenna 800 comprises a RF pad 890 establishing radio communication with another device situated in the outside of the mobile device and exchanging radio signals with the device.

The flexible antenna 800 comprises two projections, e.g. cable, extending from the RF pad 890. More particularly, a first projection 801 and second projection 802 are provided on the same side. More projection may exit on other edges of the RF pad 890. Each of the projections comprises on its end a SIM pad 800, 810. The first projection 801 comprises a first SIM pad 800 and the second projection 802 comprises a second SIM pad 810. Each SIM pad has a different orientation.

For example, the first SIM pad 800 has a diagonal edge of SIM pad directing to the left-up side 850. Thus, the angle of the direction of the diagonal edge of the first SIM pad 800 is at 45° right from the center base line of the first projection 801 pointing to the left direction.

Meanwhile, the second SIM pad 810 has a diagonal edge of SIM pad directing to the right-up side 860. The angle of the direction of the diagonal edge of the second SIM pad 810 is at 135° right from the center base line of the second projection 802 pointing to the left direction.

Advantageously, according to the invention, instead of producing several and different antennas to be sold in bundle, one single flexible antenna having several projections, e.g. cable, and corresponding SIM pads can be produced, reducing the production cost for RF pad. Advantageously, the volume of the product package can be reduced.