RFID transponder, cabin and method for manufacturing cabin

Abstract

An RFID transponder (1) comprising a radiating antenna (2) and a capsule (3) and a method for manufacturing a panel (29) comprising a capsule (3) are disclosed.

Description

Technical Field

[0001] The invention relates to an RFID transponder (Radio Frequency Identification Transponder), a pod for an RFID transponder and a method for manufacturing a pod. Background Art

[0002] RFID transponders are known. One of the disadvantages associated with known transponders is that they are not easily adaptable to mass production due to their complex structure.

[0003] US2019 / 341673 discloses a radio frequency communication module for a tire. The radio frequency communication module includes a radio frequency transponder having an electronic part. The electronic part includes an electronic chip and a main antenna electrically connected to the electronic chip via a printed circuit board. The main antenna consists of a surface mounted device (SMD) microcoil. There is a copper track terminated by a copper pad on the printed circuit board. The main antenna is connected to the copper pad on one end of the copper track, and the electronic chip is connected to the copper pad via a gold wire on the other end of the copper track. The electronic chip is placed on the printed circuit board. Summary of the invention

[0004] The object of the present invention is to provide an RFID transponder, a capsule and a manufacturing method to solve the above problems. The object of the present invention is achieved by an RFID transponder, a capsule and a manufacturing method, which are characterized by what is stated in the independent claims. Preferred embodiments of the present invention are disclosed in the dependent claims.

[0005] The advantage of an RFID transponder is that it can be produced in large quantities and it still has high quality and is very reliable.

[0006] Another advantage is that the RFID transponder can have a small size suitable for example for smaller tires or other substantially thin products.

[0007] Yet another advantage is more consistent read range performance.

[0008] RFID transponders can be used in tires, but other applications are possible, such as products that include molded parts. RFID transponders can be embedded in molded parts, such as plastic containers, information technology equipment, automotive parts, toys, or medical devices. In other words, the RFID transponders described herein can be applied in every use, where it is desirable to have a transponder inside the product, rather than adding a transponder on the surface of the product after manufacturing. However, the transponder is particularly suitable for tires.

[0009] In tires, RFID transponders are embedded in the elastomeric material of the tire in order to preserve readable information inside the tire. RFID transponders can be applied to any kind of tires, including passenger car tires, which are the most demanding targets due to the essentially thin layer of elastomeric material in the tire. The total thickness of RFID transponders in passenger car tires should not exceed a thickness of about 1.5 mm. RFID transponders must withstand the harsh manufacturing conditions of tires. The manufacturing process includes a vulcanization step performed at high temperatures and high pressures. The RFID transponder must also withstand the use of the tire throughout its life cycle. The RFID transponder must have no effect on the durability of the tire.

[0010] The RFID transponder comprises a radiating antenna (which may be a dipole antenna) and a capsule. The radiating antenna may be a three-dimensional spiral antenna or a folded planar antenna. The advantage of the folded planar antenna is that it can be deformed in the structure of the tire without affecting the performance of the antenna. The radiating antenna may also be a monopole antenna or a patch antenna.

[0011] The radiating antenna has a coupling region for the cabin. The cabin is located at the coupling region, typically within the coupling region. There may be a retainer in the cabin and / or the radiating antenna to hold the cabin in place. The coupling region is spiral in the two antenna types described above. The coupling region can be located anywhere in the radiating antenna. For example, the coupling region can be located in the middle of the antenna or at one end of the antenna. The coupling region has an adjustable pitch size to adjust the impedance matching between the cabin and the radiating antenna. The radiating antenna outside the coupling region has another pitch size that can be adjusted to adjust the resonant frequency of the antenna so that it operates within the desired frequency range. The frequency range can be in the UHF (ultra-high frequency) range, i.e. between 860 MHz and 960 MHz. The range can also be in the HF (high frequency) range, such as 13.56 MHz.

[0012] The capsule includes a first end and a second end and a housing between the first end and the second end. The housing has a central longitudinal axis. The housing is a layered structure. The cross-section of the housing can be, for example, rectangular. At least a portion of the housing is a dielectric material so that the conductive parts are electrically isolated from each other when necessary. The material of the housing can also be permeated with a dielectric.

[0013] A planar helical antenna forming a helical main antenna is located in the housing. The planar helical antenna has a first antenna end and a second antenna end. The first antenna end is connected to the second conductive connector. The second antenna end is connected to the third conductive connector. The third conductive connector is connected to the first conductive connector.

[0014] The on-chip integrated circuit is coupled to the first conductive connection and the second conductive connection. The technique used to attach the chip can be direct soldering, wire bonding or flip chip soldering.

[0015] According to a first alternative, the second antenna end and / or the third conductive connection is connected to the first conductive connection via a lead, or the first antenna end is connected to the second conductive connection via a lead. The lead may be a conductive bridge. It may be formed by printing or etching.

[0016] The first and second conductive connections and the leads are located on one of the dielectric layers. This means that they are inside the sandwich structure formed by the dielectric layers and they must be exposed before attaching the chip. The first, second and third conductive connections can be integral parts of the antenna.

[0017] According to a second alternative, there are two leads. A first lead extends from the second antenna terminal and / or the third conductive connector to the first conductive connector, thereby electrically connecting the first conductive connector and the second antenna terminal. A second lead extends from the first antenna terminal to the second conductive connector, thereby electrically connecting the second conductive connector and the first antenna terminal. The on-chip integrated circuit is coupled to the first conductive connector and the second conductive connector.

[0018] The leads and the first and second conductive connections are all located on one of the dielectric layers. This means that they are inside the sandwich structure formed by the dielectric layers and they must be exposed before attaching the chip. The first, second and third conductive connections may be integral parts of the antenna. The second alternative may be similar to the first alternative except that there are two leads.

[0019] The cabin according to the first alternative and the second alternative includes an integrated circuit inside the cabin. In order to expose the conductive contacts, a cavity is formed in a layer above the first conductive contact and the second conductive contact. The cavity can be formed, for example, by cutting or drilling a single layer of the cabin before attaching the cabin to the other layers. The cavity can be, for example, cylindrical, cubic, or any other shape that can be used to expose the conductive contacts. The integrated circuit is connected to the conductive contacts. Thereafter, the cavity can be filled with a dielectric material (such as epoxy resin). The cavity can also be unfilled. By placing the integrated circuit in the cavity, the height of the cabin is reduced and the integrated circuit is protected from external impacts.

[0020] According to a third alternative, the first end of the housing includes a first conductive connector and a second conductive connector. The second end of the housing may include a third conductive connector. The third conductive connector may be on the second end of the housing or near the second end within the housing. The first conductive connector, the second conductive connector, and the third conductive connector may be components of the antenna. The third alternative may be similar to the first alternative except that the first conductive connector and the second conductive connector are on the first end.

[0021] The housing according to the first alternative, the second alternative and the third alternative includes a layer of dielectric material, such as a ceramic material that is well resistant to high temperatures. In addition, the ceramic material can reduce the size of the cabin and have better performance. Preferred ceramic materials are those with a dielectric constant of 7.0 to 8.0 and a dielectric loss angle of 0.004 to 0.006, but other ceramic materials can also be used. In addition to the above materials, typical printed circuit board materials (such as FR4) or plastic films can be used to form a layered structure. These layers can be adhesively attached.

[0022] The housing comprises at least two layers. The housing may comprise three layers, namely a first layer, a third layer and a second layer between the first layer and the third layer. Each layer may be a planar layer with a substantially constant thickness. The thickness may vary in different layers. In addition to the above layers, there may be more layers. Additional layers may be required, for example for electrical isolation or for shielding the first layer and / or the third layer.

[0023] The housing includes a first row of continuous first through holes extending from the first layer to the third layer. The first through holes have a first end and a second end. The housing also includes a second row of continuous second through holes extending from the first layer to the third layer. The second through holes have a first end and a second end. The through holes in the second row are at different points in the longitudinal direction of the housing than the through holes in the first row.

[0024] The continuous upper arm connects the first end of the first via to the first end of the second via, and the continuous lower arm connects the second end of the first via to the second end of the second via. The arms and vias are electrically conductive.

[0025] In conjunction with the first and second alternatives explained above, the conductive portion of the capsule is preferably completely inside a dielectric material (such as a ceramic material) so that there may be no need to use an additional non-conductive coating. This is important for cost-effective manufacturing. If the dielectric material is a normal printed circuit board, a non-conductive coating may be required.

[0026] The radiating antenna and the main antenna are configured to be coupled without physical contact. This means that the radiating antenna and the main antenna are configured to be coupled inductively or capacitively. Inductive coupling is preferred.

[0027] Since the radiating antenna and the main antenna should not be in electrical contact with each other, there may be a dielectric layer between them.The outer surface of the cabin and the main antenna may be covered with a dielectric layer, or the inner surface of the radiating antenna may be electrically isolated.

[0028] The pod can also be made of two layers. If the leads are on the third layer, the second layer can be omitted. The leads can be formed on the third layer between the vias. The leads should be electrically isolated from the vias. The above options can also include additional layers, such as a layer above the first layer or a layer below the third layer.

[0029] An RFID transponder can be embedded in a product such as a tire or another product. An RFID transponder can be added, for example, in rubber or plastic. The on-chip integrated circuit can contain information about, for example, the manufacturer of the product or information related to the product, i.e., identification information has been stored in the on-chip integrated circuit. An RFID reader can stimulate the RFID transponder so that the information can be read.

[0030] One possibility of manufacturing the cabin according to the first alternative and the second alternative is as follows: The main antenna can be manufactured by using low temperature co-fired ceramic (LTCC) technology. A blank containing a layer of ceramic particles mixed with a polymer binder is formed. In order to form a through hole, the blank is punched. The through hole is made conductive, for example, by electroplating the through hole with a conductive material. The arm and the lead can be formed by printing. In order to expose the conductive contacts, a cavity is formed in the layer above the first conductive contact and the second conductive contact. The cavity can be formed, for example, by cutting or drilling a single layer of the cabin before attaching the cabin to the other layers. The cavity can be, for example, cylindrical, cubic, or any other shape that can be used to expose the conductive contacts. Thereafter, the layers are laminated together and fired at a temperature below 1000° C. so that the polymer binder burns and the ceramic particles sinter together. The integrated circuit is connected to the conductive contacts. Thereafter, the cavity can be filled with a dielectric material (such as epoxy resin). The cavity can also be unfilled. By placing the integrated circuit in the cavity, the height of the cabin is reduced.

[0031] When the first conductive contact and the second conductive contact are located on one of the dielectric layers, multiple parallel and / or continuous chambers (e.g., 500 chambers) can be manufactured at one time. The multiple chambers are first manufactured as a panel, and then the chambers are cut from the panel to form individual chambers. The above manufacturing method improves manufacturing accuracy, yield, and productivity.

[0032] Another possibility for manufacturing a cabin according to the first alternative and the second alternative is to use a printed circuit (PCB) core and prepreg as the first dielectric layer and the second dielectric layer. The PCB core has an upper surface and a lower surface. The prepreg has an upper surface and a lower surface.

[0033] The dielectric PCB core has conductive layers on both sides. The conductive layers can be copper. A photoresist dry film containing a circuit pattern is laminated on the two conductive layers by heating. The film is removed thereafter, but the circuit pattern remains on the conductive layers, i.e., the circuit pattern on the upper surface of the first layer includes a pattern for the upper arm, and the circuit pattern on the lower surface of the first layer includes a pattern for the lead. The conductive layers are etched so that only the circuit pattern remains on the upper and lower surfaces. A cavity is formed by drilling a hole into the PCB core. The cavity exposes the first conductive connector and the second conductive connector so that a chip can be attached.

[0034] The prepreg is laminated to the PCB core in such a way that the lower surface of the first layer and the upper surface of the second layer are in contact. A conductive material foil such as copper is laminated to the lower surface of the prepreg.

[0035] Thereafter, through holes are formed. The through holes are plated to make them conductive.

[0036] A photoresist dry film including a circuit pattern is laminated on the lower surface of the prepreg by heating. The film is removed thereafter, but the circuit pattern remains on the conductive foil, i.e., the circuit pattern on the lower surface of the second layer includes a pattern for the lower arm. The conductive foil is etched so that only the circuit pattern remains on the lower surface. A solder mask layer is applied on the upper surface of the first layer and the lower surface of the second layer to protect the upper and lower surfaces of the cabin.

[0037] The on-chip integrated circuit is fixed in the cavity. The first and second conductive connectors are connected to corresponding pads of the chip. Thereafter, the cavity may be filled with a resin that protects the chip 15, such as epoxy resin.

[0038] Another possibility for manufacturing the chamber according to the first alternative and the second alternative is to attach the integrated circuit on one of the layers and connect it to the first and second conductive contacts, and then laminate the layer with the other layers so that the integrated circuit is embedded in the chamber. No cavity is then needed. In other words, the manufacturing process is the same as for the chamber, except that the cavity is omitted and the integrated circuit is attached before the lamination step. The layers can be made of printed circuit board material such as FR4.

[0039] One possibility for manufacturing the cabin according to the third alternative is as follows: The main antenna can be manufactured by using low temperature co-fired ceramic (LTCC) technology. A blank containing layers of ceramic particles mixed with a polymer binder is formed. To form through holes, the blank is punched. The through holes are made conductive by filling them with conductive material. Arms and leads can be formed by printing. Thereafter, the layers are laminated together and fired at a temperature below 1000°C so that the polymer binder burns and the ceramic particles sinter together. A first conductive connector and a second conductive connector are at one end of the cabin. An integrated circuit is connected to the first conductive connector and the second conductive connector. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The present invention will be described in more detail below by means of preferred embodiments with reference to the accompanying drawings, in which

[0041] Figure 1 shows a perspective view of an RFID transponder;

[0042] Figure 2 shows a side view of an RFID transponder;

[0043] Figure 3 A perspective view of the cabin is shown;

[0044] Figure 4 A side view of the cabin is shown;

[0045] Figure 5 A side view of another cabin is shown;

[0046] Figure 6 A schematic diagram of the main antenna and leads is shown;

[0047] Figure 7 A schematic diagram showing the main antenna and two leads is shown;

[0048] Figures 8a to 8c A perspective view of the cabin is shown;

[0049] Fig. 9 shows a side view of a radiating antenna;

[0050] Fig.10 and Fig.11 Shows Fig. 9 The principle of antenna;

[0051] Fig.12 A perspective view of the cabin is shown;

[0052] Fig.13 A side view of the cabin is shown;

[0053] Fig.14 A first end of the cabin is shown;

[0054] Fig.15 is a top view schematic diagram of the panel;

[0055] Fig.16 A side view of the cabin is shown. DETAILED DESCRIPTION

[0056] Figure 1 1 shows a perspective view of an RFID transponder 1. The RFID transponder 1 comprises a radiating antenna 2 and a capsule 3. The radiating antenna 2 may be Figure 1 The helical dipole antenna shown. The radiating antenna 2 has a coupling region 4 for a capsule 3. The coupling region 4 comprises a helix.

[0057] Figure 2 Shows something like Figure 1 RFID transponder 1 of the embodiment of the present invention is a side view of an RFID transponder. The RFID transponder 1 comprises a radiating antenna 2 and a compartment 3. The coupling region 4 comprises a spiral and has a pitch p1. The radiating antenna 2 outside the coupling region 4 comprises a spiral and has a pitch p2 or a pitch p3. The pitches p1, p2 and p3 may be equal to or different from each other. The spiral has outer diameters D1, D2 and D3 which may be equal to or different from each other. Typically D1 is slightly larger than D3, and D3 and D2 are equal.

[0058] Figure 3 and Figure 4 A capsule 3 is shown. The capsule 3 comprises a first end 5 and a second end 6 and a housing 7 having a layered structure between the first end 5 and the second end 6. At least a portion of the housing 7 is a dielectric material.

[0059] The housing 7 comprises layers of dielectric material, such as ceramic material. The housing comprises a first layer 19 and a third layer 21 and a second layer 20 between the first layer 19 and the third layer 21. Each layer may be a planar layer with a substantially constant thickness. The thickness may vary in different layers. In addition to the above layers, there may be more layers. At least one ceramic layer may be present between the first layer and the second layer and / or between the second layer and the third layer. At least one ceramic layer may also be present on the first layer 19 and / or below the third layer 21. Figure 4 and Figure 5 The ceramic layer 16 on the first layer 19 is shown.

[0060] The layered structure includes a lead 8 between the first end 5 and the second end 6. The lead 8 may be a printed lead or another conductive bridge. The lead is formed on one of the layers. The lead may be formed on the second layer 20. The first conductive connector 9 and the second conductive connector 10 are located on one of the dielectric layers (e.g. Figure 4 and Figure 5 On the second layer 20) shown in FIG.

[0061] A planar helical antenna forming a helical main antenna 12 is located in the housing 7. The helical main antenna 12 has a first antenna end 13 and a second antenna end 14. The third conductive connection 11 is configured to extend from the second antenna end 14. The first antenna end 13 is connected to the second conductive connection 10. The second antenna end 14 is connected to the third conductive connection 11. The third conductive connection 11 is connected to the first conductive connection 9 through the lead 8. The integrated circuit on the chip 15 is coupled to the first conductive connection 9 and the second conductive connection 10. The technology for attaching the chip 15 can be direct soldering, wire bonding or flip chip soldering.

[0062] The housing 7 includes a first row 22 of continuous first through holes 23 extending from the first layer 19 to the third layer 21. The first through holes 23 have a first end 23a and a second end 25b. The housing 7 also includes a second row 24 of continuous second through holes 25 extending from the first layer 19 to the third layer 21. The second through holes 25 have a first end 25a and a second end 25b. The through holes 25 in the second row 24 are at different points in the longitudinal direction of the housing 7 compared to the through holes 23 in the first row 22.

[0063] The continuous upper arm 26 connects the first end 23a of the first through hole 23 to the first end 25a of the second through hole 25, and the continuous lower arm 27 connects the second end 23b of the first through hole 23 to the second end 25b of the second through hole 25. The arms 26, 27 and the through holes 23, 25 are electrically conductive. The arms 26, 27 extend diagonally relative to the longitudinal direction of the cabin. The arms 26, 27 cross in a projection perpendicular to the plane of the layers 19, 20, 21. The arms 26, 27 may be perpendicular to each other in the protrusion.

[0064] The last through hole 25L in the longitudinal direction D of the housing 7 (which may be in any row 22, 24) extends from the first layer 19 to the second layer 20. The second end 25Lb of the last through hole 25L and the second end 8b of the lead 8 form the third conductive connection 11. The first conductive connection 9 extends from the first end 8a of the lead 8 on the surface of the second layer 20. The second conductive connection 10 extends from the first end 23a of the first through hole 23 on the surface of the second layer 20.

[0065] Thus, the helical main antenna, which in this case is a planar helical antenna, is formed as follows: there are conductive vias 23, 25 and conductive arms 26 and 27. The antenna repeats the following sequence: from the first end 25a of via 25 to the second end 25b of via 25, from the second end 25b of via 25 to arm 27, from arm 27 to the second end 23b of via 23, from the second end 23b of via 23 to the first end 23a of via 23, from the first end 23a of via 23 to arm 26, and from arm 26 to the first end 25a of via 25. The sequence could also start from another row, i.e. via 23 being the first in the sequence.

[0066] Arm 26 may be formed on the front face of first layer 19, and arm 27 may be formed on the front face of third layer 21. Vias 23, 25 extending through first layer 19 and second layer 20 connect arm 26 on first layer 21 and arm 27 on third layer 21.

[0067] Remove the layer above the second layer 20 (ie Figure 4 The first conductive connection member 9 and the second conductive connection member 10 are exposed. Figures 8a to 8c As shown, cavity 28 is formed. After the connectors 9 and 10 have been exposed, the integrated circuit (IC) on the chip 15 is coupled to the first conductive connector 9 and the second conductive connector 10. A suitable material for the antenna and the conductive connector is silver. The conductive connector can be plated with tin or other suitable materials. Cavity 28 can be filled with epoxy resin, but it may not be necessary in every case.

[0068] The structure of the cabin 3 can be varied with respect to the order of the layers 19, 20, 21, i.e., the layers 19, 20, 21 can exchange positions. The second layer 20 may not include the lead 8. The lead 8 may be above the first layer 19, or below the third layer 21. Naturally, the conductive connections 9, 10, 11 should be redistributed in those cases. For example, the last through hole 25L may extend through the third layer 21 to the layer below the third layer 21 (to which the lead 8 extends). The second layer 20 can also be omitted. However, the second layer 20 between the first layer 19 and the third layer 21 is preferred in order to achieve the best inductance (coupling performance) of the radiating antenna 2.

[0069] The capsule 3 can also be made of two layers 19, 21. If the lead 8 is on the third layer 21, the second layer 20 can be omitted. The lead 8 can be formed on the third layer between the via 23 and the via 25. The lead 8 should be electrically isolated from the via 23 and the via 25. The above options can also include at least one additional layer, such as a layer above the first layer 19 or a layer below the third layer 21.

[0070] The two-layer structure may also be as follows: the second layer 20 is omitted. The upper arm 26 may be formed on the front face of the first layer 19, and the lower arm 27 may be formed on the rear face of the third layer 21. The lead 8 may be formed on the front face of the third layer 21. The through holes 23, 25 extend through the layers 19, 21, thereby electrically connecting the arms 26, 27.

[0071] The capsule 3 may be in the shape of a rectangular prism. The rectangular prism may have a square cross section perpendicular to its longitudinal axis, ie its sides are of equal length in the height and depth directions.

[0072] Figure 5 A side view of another capsule 3 is shown. In addition to the lead 8, the capsule 3 has Figure 4 The same structure in . Figure 5 The illustrated capsule 3 comprises a first lead 80a connecting the first conductive connection 9 and the third conductive connection 11 and a second lead 80b starting from the first antenna end 13 and continuing to the second conductive connection 10. Thus, there are two leads 80a, 80b which are able to convey the conductive connections 9, 10 along the second layer wherever required.

[0073] Figure 6 A schematic diagram of a main antenna 12 having one lead 8 is shown. Figure 6 The structure in corresponds to Figure 3 and Figure 4The main antenna has a first antenna terminal 13 and a second antenna terminal 14. The second conductive connector 10 is in electrical contact with the first antenna terminal 13. The lead 8 extends from the second antenna terminal 14 to the first conductive connector 9, thereby electrically connecting the first conductive connector 9 and the second antenna terminal 14. The lead 8 and the first conductive connector 9 and the second conductive connector 10 are located in one of the dielectric layers (such as Figure 4 The on-chip integrated circuit 15 is connected to the first conductive connection 9 and the second conductive connection 10.

[0074] Figure 7 A schematic diagram of a main antenna 12 having two leads 80a, 80b is shown. Figure 7 The structure in corresponds to Figure 5 The main antenna has a first antenna terminal 13 and a second antenna terminal 14. A first lead 80a extends from the second antenna terminal 14 to the first conductive connector 9, thereby electrically connecting the first conductive connector 9 and the second antenna terminal 14. A second lead 80b extends from the first antenna terminal 13 to the second conductive connector 10, thereby electrically connecting the second conductive connector 10 and the first antenna terminal 13. The leads 80a, 80b and the first conductive connector 9 and the second conductive connector 10 are all located in one of the dielectric layers (such as Figure 5 The on-chip integrated circuit 15 is connected to the first conductive connection 9 and the second conductive connection 10.

[0075] FIG. 8 shows a schematic perspective view of the cabin 3 . Figure 8a The capsule 3 is shown including an integrated circuit near the end of the capsule 3. A cylindrical cavity 28 has been formed in the capsule 3 in order to expose the first 9 and second 10 conductive connections so that the integrated circuit 15 can be attached. Figure 8a The alternative shown in may have the following features: Figure 4 and Figure 6 Only one lead 8 is explained.

[0076] Figure 8b A capsule 3 is shown comprising an integrated circuit 15 located in the middle of the capsule 3. A cylindrical cavity 28 has been formed in the capsule 3 in order to expose the first 9 and second 10 conductive connections so that the integrated circuit 15 can be attached. Figure 8b The alternative shown in may have the following features: Figure 5 and Figure 7 Two leads 80a, 80b are explained.

[0077] Figure 8c A capsule 3 is shown comprising an integrated circuit 15 in the middle of the capsule 3. A cuboid cavity 28 has been formed in the capsule 3 in order to expose the first 9 and second 10 conductive connections so that the integrated circuit can be attached. Figure 6The alternative shown in c may have two leads 80a, 80b, such as in combination with Figure 5 Explained.

[0078] Fig. 9 The radiating antenna 2 is shown from above. The radiating antenna 2 is a folded planar antenna which can replace Figure 1 and 2 The helical radiating antenna 2 shown uses a radiating antenna 2 having a coupling region 4 for a capsule 3. The coupling region 4 comprises a helix, but, unlike the antenna, is planar, ie it extends in a two-dimensional plane. Fig. 9 Also shown are the pitches p1 and p2 associated with the folded planar antenna.

[0079] Fig.10 and Fig.11 The outside of the coupling region 4 is shown Fig. 9 The principle of the folded planar antenna. Outside the coupling region 4 Fig. 9 The folded planar antenna of the embodiment of the present invention has a circular profile. The circles are regularly spaced in two parallel straight lines in such a way that every other circle is in the first line and every other circle is in the second line. Each circle has a radius r. The distance a is the distance between the midpoints of the circles in the first line and the second line. The distance b is the distance between the midpoints of consecutive circles in the longitudinal direction L of the antenna. Different antenna shapes can be achieved by changing at least one of the radius r, the distance a or the distance b.

[0080] Fig.12 and Fig.13 A capsule 3 is shown. The capsule 3 comprises a first end 5 and a second end 6 and a housing 7 having a layered structure between the first end 5 and the second end 6. At least a portion of the housing 7 is a dielectric material.

[0081] The layered structure comprises a lead 8 between the first end 5 and the second end 6. The lead 8 may be a printed lead or another conductive bridge. The first end 5 of the housing comprises a first 9 and a second 10 conductive connection.

[0082] A helical main antenna 12 (such as a planar helical antenna) is located in the housing 7. The helical main antenna 12 has a first antenna end 13 and a second antenna end 14. The third conductive connector 11 is configured to extend from the second antenna end 14. The first antenna end 13 is connected to the second conductive connector 10. The second antenna end 14 is connected to the third conductive connector 11. The third conductive connector 11 is connected to the first conductive connector 9 through the lead 8. The on-chip integrated circuit 15 is coupled to the first conductive connector 9 and the second conductive connector 10. The technology for attaching the chip 15 can be direct soldering or wire bonding. An example of the first end 5 is shown in FIG. Fig.14 Shown in.

[0083] The housing 7 comprises a layer of dielectric material, such as a ceramic material. The housing comprises a first layer 19 and a third layer 21 and a second layer 20 between the first layer 19 and the third layer 21. Each layer may be a planar layer with a substantially constant thickness. The thickness may vary in different layers. In addition to the above layers, there may be more layers. At least one ceramic layer may be present between the first layer and the second layer and / or between the second layer and the third layer. At least one ceramic layer may also be present on the first layer 19 and / or below the third layer 21. Fig.13 The ceramic layer 16 on the first layer 19 is shown.

[0084] The housing 7 includes a first row 22 of continuous first through holes 23 extending from the first layer 19 to the third layer 21. The first through holes 23 have a first end 23a and a second end 25b. The housing 7 also includes a second row 24 of continuous second through holes 25 extending from the first layer 19 to the third layer 21. The second through holes 25 have a first end 25a and a second end 25b. The through holes 25 in the second row 24 are at different points in the longitudinal direction of the housing 7 compared to the through holes 23 in the first row 22.

[0085] The continuous upper arm 26 connects the first end 23a of the first through hole 23 to the first end 25a of the second through hole 25, and the continuous lower arm 27 connects the second end 23b of the first through hole 23 to the second end 25b of the second through hole 25. The arms 26, 27 and the through holes 23, 25 are electrically conductive. The arms 26, 27 extend diagonally relative to the longitudinal direction of the cabin. The arms 26, 27 cross in a projection perpendicular to the plane of the layers 19, 20, 21. The arms 26, 27 may be perpendicular to each other in the protrusion.

[0086] The last through hole 25L in the longitudinal direction D of the housing 7 (which can be in any row 22, 24) extends from the first layer 19 to the second layer 20. The second end 25Lb of the last through hole 25L and the second end 8b of the lead 8 form a third conductive connection 11. The first conductive connection 9 extends from the first end 8a of the lead 8 toward the first end 5 of the cabin 3. The second conductive connection 10 extends from the first end 23a of the first through hole 23 toward the first end 5 of the cabin 3. The on-chip integrated circuit (IC) 15 placed on the first end 5 of the cabin 3 is coupled to the first conductive connection 9 and the second conductive connection 10. A suitable material for the antenna and the conductive connection is silver. The conductive connection can be electroplated with tin or other suitable materials.

[0087] Thus, the helical main antenna, which in this case is a planar helical antenna, is formed according to the second embodiment as follows: there are conductive vias 23, 25 and conductive arms 26, 27. The antenna repeats the following sequence: from the first end 25a of the via 25 to the second end 25b of the via 25, from the second end 25b of the via 25 to the arm 27, from the arm 27 to the second end 23b of the via 23, from the second end 23b of the via 23 to the first end 23a of the via 23, from the first end 23a of the via 23 to the arm 26, and from the arm 26 to the first end 25a of the via 25. The sequence could also start from another row, i.e. the via 23 is the first in the sequence.

[0088] The structure of the cabin 3 can be varied with respect to the order of the layers 19, 20, 21, i.e., the layers 19, 20, 21 can exchange positions. The second layer 20 may not include the lead 8. The lead 8 may be above the first layer 19, or below the third layer 21. Naturally, the conductive connections 9, 10, 11 should be redistributed in those cases. For example, the last through hole 25L may extend through the third layer 21 to the layer below the third layer 21 (to which the lead 8 extends). The second layer 20 can also be omitted. However, the second layer 20 between the first layer 19 and the third layer 21 is preferred in order to achieve the best inductance (coupling performance) of the radiating antenna 2.

[0089] The capsule 3 can also be made of two layers 19, 21. If the lead 8 is on the third layer 21, the second layer 20 can be omitted. The lead 8 can be formed on the third layer between the vias 23, 25. The lead 8 should be electrically isolated from the vias 23, 25. The above options can also include at least one additional layer, such as a layer above the first layer 19 or a layer below the third layer 21.

[0090] The structure may also vary with respect to the placement of the chip 15. Instead of having the chip 15 on the first end 5 of the capsule 3, the chip 15 may be placed anywhere on the outer surface of the capsule 3. The conductive connections 9, 10, 11 should be re-deployed accordingly. However, the first end 5 of the capsule 3 is the preferred choice.

[0091] The preferred shape of the capsule 3 is a rectangular prism. The rectangular prism may have a square cross-section perpendicular to its longitudinal axis, ie its sides are of equal length in height and depth.

[0092] Fig.15 A schematic diagram of a panel 29 is shown. The panel 29 comprises continuous and / or parallel cells 3 which are cut after the other stages of manufacture have been completed.

[0093] Fig.16A side view of a capsule 3 comprising a printed circuit board (PCB) core and prepreg as a first dielectric layer 19 and a second dielectric layer 20 is shown. The technical content disclosed in connection with the capsule comprising ceramic layers is directly applicable to a suitable extent to Fig.16 cabin.

[0094] The PCB core has an upper surface 19a and a lower surface 19b. The prepreg 20 has an upper surface 20a and a lower surface 20b.

[0095] Through holes 23, 25 have been drilled through the layers 19, 20. An upper arm 26 has been formed on the upper surface 19a of the PCB core 19. A lower arm 27 is formed on the lower surface 20b of the prepreg 20. Leads 8 have been formed on the lower surface 19b of the PCB core 19. An on-chip integrated circuit 15 has been connected to the first conductive connector 9 and the second conductive connector 10.

[0096] according to Fig.16 The compartment 3 has been separated from the panel 29 comprising consecutive and / or parallel compartments 3, as Fig.15 As shown. Each compartment 3 of the panel 29 is manufactured at the same time. Each compartment 3 can be manufactured as follows:

[0097] The dielectric PCB core 19 has a conductive layer on two faces 19a, 19b. The conductive layer can be copper. A photoresist dry film containing a circuit pattern is laminated on the two conductive layers 19a, 19b by heating. The film is removed thereafter, but the circuit pattern remains on the conductive layer, i.e., the circuit pattern on the upper surface 19a of the first layer 19 includes a pattern for the upper arm 26, and the circuit pattern on the lower surface 19b of the first layer 19 includes a pattern for the lead 8. The conductive layer is etched so that only the circuit pattern remains on the upper surface 19a and the lower surface 19b. A cavity 28 is formed by drilling a hole into the PCB core 19. The cavity 28 exposes the first conductive connector 9 and the second conductive connector 10 so that the chip 15 can be attached.

[0098] The prepreg 20 is laminated to the PCB core 20 in such a way that the lower surface 19b of the first layer 19 and the upper surface 20a of the second layer 20 are in contact. A foil of a conductive material such as copper is laminated to the lower surface 20b of the prepreg 20. The foil may be attached by a vacuum lamination press.

[0099] After that, through holes 23, 25 are formed. Through holes 23, 25 may be formed by a CNC PCB drilling machine. Through holes 23, 25 are plated to make them conductive.

[0100] A photoresist dry film including a circuit pattern is laminated on the lower surface 20b of the prepreg 20 by heating. The film is removed thereafter, but the circuit pattern remains on the conductive foil, i.e., the circuit pattern on the lower surface 20b of the second layer 20 includes a pattern for the lower arm 27. The conductive foil is etched so that only the circuit pattern remains on the lower surface 20b. Layers 30, 31 of solder mask are applied on the upper surface 19a of the first layer 19 and the lower surface 20b of the second layer 20 to protect the upper and lower surfaces of the cabin 3.

[0101] The on-chip integrated circuit 15 is fixed in the cavity 28 by using a die attach adhesive. The first conductive connection 9 and the second conductive connection 10 are connected to the corresponding pads of the chip 15 by a wire bonding method. Thereafter, the cavity 28 may be filled with a resin protecting the chip 15, such as epoxy resin.

[0102] It is obvious to a person skilled in the art that, as technology advances, the inventive concept can be implemented in various ways.The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.

Claims

1. An RFID transponder (1), comprising: a radiating antenna (2) and a capsule (3), the radiating antenna (2) having a coupling region (4) for the capsule (3), The capsule (3) is located at the coupling region (4), and the capsule (3) comprises a first end (5) and a second end (6) and a shell (7) between the first end (5) and the second end (6), at least a portion of the shell (7) comprises dielectric layers stacked on top of each other, a planar helical antenna, the planar helical antenna forming a helical main antenna (12), the planar helical antenna being configured to extend between the first end (5) and the second end (6), The planar helical antenna has a first antenna end (13) and a second antenna end (14), The first antenna end (13) is connected to the second conductive connecting member (10), and the second antenna end (14) is connected to the first conductive connecting member (9). an on-chip integrated circuit (15), the on-chip integrated circuit being coupled to the first conductive connection (9) and the second conductive connection (10) inside the compartment (3), and At least one of the first conductive connection member (9) or the second conductive connection member (10) is electrically connected to the corresponding antenna terminal (13, 14) through a lead wire (8, 80a, 80b), and The radiating antenna (2) and the main antenna (12) are configured to be coupled without physical contact.

2. The RFID transponder according to claim 1, characterized in that: The radiating antenna (2) and the main antenna (12) are configured to be coupled by inductive coupling.

3. The RFID transponder according to claim 1 or 2, characterized in that: The radiating antenna (2) is a three-dimensional helical antenna.

4. An RFID transponder according to any preceding claim, characterized in that The radiating antenna (2) is a folded planar antenna.

5. An RFID transponder according to any preceding claim, characterized in that The radiating antenna (2) comprises a helical coupling region (4).

6. An RFID transponder according to any preceding claim, characterized in that The cabin (3) is located within the spiral coupling area (4).

7. A capsule (3) for an RFID transponder (1), the capsule (3) comprising a first end (5) and a second end (6) and a housing (7) located between the first end (5) and the second end (6), at least a portion of the housing (7) comprising dielectric layers stacked on top of each other, A planar helical antenna forming a helical main antenna (12) is configured to extend between the first end (5) and the second end (6), The planar helical antenna has a first antenna end (13) and a second antenna end (14), The first antenna end (13) is connected to the second conductive connecting member (10), and the second antenna end (14) is connected to the first conductive connecting member (9). An integrated circuit on a chip (15) is coupled to the first conductive connection (9) and the second conductive connection (10) inside the compartment (3), and At least one of the first conductive connection member (9) or the second conductive connection member (10) is electrically connected to a corresponding antenna terminal (13, 14) via a lead wire (8, 80a, 80b).

8. The cabin according to claim 7, characterized in that The first conductive connection member (9) is electrically connected to the first antenna end (13) via a lead wire (8).

9. The cabin according to claim 7, characterized in that The second conductive connection member (10) is electrically connected to the second antenna end (14) via a lead wire (8).

10. The cabin according to claim 7, characterized in that The first conductive connection member (9) is electrically connected to the first antenna end (13) via a lead wire (80b), and the second conductive connection member (10) is electrically connected to the second antenna end (14) via a lead wire (80a).

11. A cabin according to any one of the preceding claims 7 to 10, characterised in that The lead (8, 80a, 80b) is on one of the dielectric layers.

12. A capsule according to any one of the preceding claims 7 to 11, characterised in that The planar helical antenna comprises through holes (23, 25) and arms (26, 27).

13. A capsule according to any one of the preceding claims 7 to 12, characterised in that The leads (8, 80a, 80b) are printed leads.

14. A capsule according to any one of the preceding claims 7 to 13, characterised in that The chamber (3) comprises a cavity (28) for an integrated circuit on the chip (15).

15. A method for manufacturing a panel (29) comprising a cabin (3), the method comprising: - drilling holes (23, 25) into the dielectric layers (19, 20, 21), - making the through holes (23, 25) electrically conductive, - forming arms (26, 27), leads (8, 80a, 80b) and first conductive connections (9) and second conductive connections (10) on the dielectric layers (19, 20, 21), - laminating said dielectric layers (19, 20, 21), - attaching the integrated circuit on the chip (15) to the first conductive connection (9) and the second conductive connection (10) in such a way that the chip (15) remains inside the compartment (3), and - Cutting the panels into individual compartments (3).

16. The method according to claim 15, characterized in that The method includes forming a green sheet including a layer of ceramic particles mixed with at least one polymer binder.

17. The method according to claim 15 or 16, characterized in that The method includes firing at a temperature below 1000° C. to burn the polymer binder and sinter the ceramic particles together.

18. The method according to any one of the preceding claims 15 to 17, characterized in that The method includes forming a cavity (28) to expose the first conductive connection (9) and the second conductive connection (10).

19. The method according to claim 18, characterized in that The method includes filling the cavity (28) with a dielectric resin.

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