JPH1198061A - Loop antenna and information processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems of a communication area and radio wave laws by combining n loop antennas which have an open area that is 1/n of the open area of a desired loop antenna and also configuring it with one conductor. SOLUTION: A loop antenna 62 is configured by winding an antenna of a radio card system in turn so that four loop antenna elements 61 which are 1/4 of a desired antenna size can be formed. Electric fields due to current that flows into sides inside the elements 61 are mutually negated, and a radiation electric field pattern of a remote field is the same with the radiation pattern of an antenna in which current flows through only an outermost circumference. An effect of geometrical distance with divided antennas appears at a close distance and radiation field intensity at angles except the normal line direction of a radio card is increased. With this, a practical communication area is drastically expanded without increasing the radiation field intensity of radio wave laws. A small loop antenna can be arranged inside a desired loop antenna.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply for a wireless card by performing wireless transmission / reception with a battery-less wireless card as an information storage medium having a portable wireless communication function. The present invention relates to a loop antenna used for a wireless card reader / writer that performs predetermined information processing such as transmission of data and transmission and reception of data. The present invention also relates to an information processing device such as a wireless card reader / writer using the loop antenna.

[0002]

2. Description of the Related Art Recently, a so-called batteryless wireless card has been developed as a portable information storage medium having a wireless communication function, and is being put into practical use. In a wireless card system using a wireless card of this kind, transmission and reception of power and data to and from the wireless card are performed by wirelessly transmitting and receiving to and from the wireless card using a wireless card reader / writer. For example, predetermined information processing is performed.

[0003] In recent years, such a wireless card system has been introduced into an entrance / exit management system, an amusement park, a ski resort, and the like. Furthermore, introduction of a wireless card system is also considered in a system that handles monetary information such as a general-purpose electronic ticket and electronic money.

Conventionally, the communication area is mainly used for entry / exit management, and its communication area has been discussed only with respect to the distance on the central axis between the wireless card reader / writer and the wireless card.

[0005]

In a conventional wireless card system, a wireless card and a wireless card reader are used.
It has been said that the communication of the writer's antenna should be performed in the most stable position, that is, when the antenna of the wireless card reader / writer and the antenna of the wireless card are in front of each other on the central axis.

[0006] In the specifications, the communication distance is defined as the communication distance of the wireless card system. However, in a wireless card system used for an automatic ticket gate, for example, it is necessary to communicate with a wireless card reader / writer while the wireless card is moving. Therefore, the wireless card reader / writer must secure a communication distance while securing a wide communication area.

As a solution to the above problem, it is conceivable to increase the radiated electric field intensity of the antenna. However, since the radiated electric field strength is regulated by the Radio Law,
It is impossible to increase the intensity of the radiated electric field unnecessarily.

Accordingly, an object of the present invention is to provide a loop antenna and an information processing apparatus which can solve the problems of the communication area and the problem of the Radio Law, which are conventional problems.

[0009]

According to the loop antenna of the present invention, a desired loop antenna has an opening area of n (n: integer).
The opening area of the desired loop antenna is realized by combining n loop antenna elements having an area divided into two, and this is constituted by one conductor.

Further, the loop antenna of the present invention includes a second loop antenna having an opening area smaller than the communication area inside a first loop antenna having an opening area corresponding to a desired communication area. It is arranged so that a predetermined radiated electric field intensity is obtained by a combined radiated electric field intensity of the first loop antenna having a large opening area and the second loop antenna having a small opening area.

Further, the loop antenna of the present invention is provided with a back member formed by laminating a plate-shaped magnetic material and a metal plate behind a loop antenna having an opening area corresponding to a desired communication area. Become.

In the loop antenna of the present invention, a conductor is provided around a loop antenna having an opening area corresponding to a desired communication area, and the conductor is grounded. Also,
The loop antenna according to the present invention is constituted by a twisted pair wire, one end of one conductor of the twisted pair wire is used as an input end and the other end is grounded, and one end of the other conductor of the twisted pair wire is grounded and the other end is grounded. The ends are left open.

In the loop antenna of the present invention, a band-shaped conductor is arranged on the loop antenna having an opening area corresponding to a desired communication area along the loop antenna and a closed loop is not formed. A slit is provided in the middle of the conductor, and the conductor is grounded.

Further, the loop antenna of the present invention is constituted by a coaxial cable, one end of a core wire of the coaxial cable is used as an input end and the other end is grounded, and one end of a shield wire of the coaxial cable is grounded. At the same time, the other end is opened.

Further, the loop antenna of the present invention is constituted by first and second loop antennas which resonate respectively, and by adjusting the band of the first and second loop antennas and the coupling between the antennas, It is configured to secure a desired band.

Further, the information processing apparatus of the present invention combines n loop antenna elements each having an area obtained by dividing an opening area of a desired loop antenna into n (n: an integer) by combining the opening area of the desired loop antenna. And a wireless communication means for performing wireless transmission and reception between the antenna and an external wireless communication medium through the loop antenna; Processing means for performing predetermined information processing based on the result of transmission and reception by the communication means.

Further, the information processing apparatus of the present invention has a second loop antenna having an opening area smaller than the communication area inside the first loop antenna having an opening area corresponding to a desired communication area. And a loop antenna configured to obtain a predetermined radiated electric field strength by a combined radiated electric field strength of a first loop antenna having a large opening area and a second loop antenna having a small opening area, and the loop antenna Wireless communication means for performing wireless transmission / reception to / from an external wireless communication medium via a wireless communication medium, and processing means for performing predetermined information processing based on a result of transmission / reception by the wireless communication means.

In the information processing apparatus according to the present invention, a back member formed by laminating a plate-shaped magnetic body and a metal plate is disposed behind a loop antenna having an opening area corresponding to a desired communication area. A loop antenna, wireless communication means for wirelessly transmitting and receiving to and from an external wireless communication medium via the loop antenna, and processing means for performing predetermined information processing based on a result of transmission and reception by the wireless communication means. I have it.

The information processing apparatus according to the present invention further comprises a loop antenna having a conductor disposed around a loop antenna having an opening area corresponding to a desired communication area, and grounding the conductor. Wireless communication means for transmitting and receiving wirelessly to and from an external wireless communication medium via
Processing means for performing predetermined information processing based on the result of transmission and reception by the wireless communication means.

The information processing apparatus according to the present invention comprises a twisted pair wire, one end of one conductor of the twisted pair wire is used as an input end, the other end is grounded, and the other conductor of the twisted pair wire is connected to the other end of the twisted pair wire. One end is grounded and the other end is open, a loop antenna is opened, a wireless communication means for wirelessly transmitting and receiving to and from an external wireless communication medium via the loop antenna, and a transmission / reception result by the wireless communication means is provided. Processing means for performing predetermined information processing based on the information processing.

Further, the information processing apparatus of the present invention arranges a band-shaped conductor along a loop antenna on a loop antenna having an opening area corresponding to a desired communication area and does not form a closed loop. A loop antenna provided with a slit in the middle of the conductor, and grounding the conductor; a wireless communication unit for performing wireless transmission and reception between the loop antenna and an external wireless communication medium; Processing means for performing predetermined information processing based on the result of transmission and reception by the wireless communication means.

The information processing apparatus of the present invention comprises a coaxial cable, one end of a core wire of the coaxial cable is used as an input end, the other end is grounded, and one end of a shielded wire of the coaxial cable is grounded. A loop antenna whose other end is open, a wireless communication means for performing wireless transmission / reception with an external wireless communication medium via the loop antenna, and a predetermined Processing means for performing information processing.

Further, the information processing apparatus of the present invention is constituted by first and second loop antennas which resonate, respectively, and by adjusting the band of the first and second loop antennas and the coupling between the antennas. A loop antenna configured to secure a desired band, wireless communication means for wirelessly transmitting and receiving to and from an external wireless communication medium via the loop antenna, and a transmission / reception result of the wireless communication means. Processing means for performing predetermined information processing based on the information processing.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows a configuration of a wireless card system according to the present embodiment. In FIG. 1, 1 is a wireless card reader / writer as an information processing device, 2 is a loop antenna of the wireless card reader / writer 1, and 3 is a higher-level device of the wireless card reader / writer 1 (for example, a personal computer or an automatic ticket gate device). Is a battery-less wireless card as a wireless communication medium, and is basically composed of a loop antenna 5 and an integrated circuit (IC) 6.

FIG. 2 shows an example of a basic configuration of the wireless card reader / writer 1. In FIG. 2, reference numeral 11 denotes a transmission circuit, and 12 denotes a reception circuit, to which the loop antenna 2 is connected. Reference numeral 13 denotes a control circuit for executing various processes, to which the transmission circuit 11 and the reception circuit 12 are connected.

The outline of the operation will be briefly described below. Transmission data is created in the control circuit 13 and the transmission circuit 1
Sent to 1. The transmission circuit 11 modulates transmission data and transmits the modulated data from the loop antenna 2 to the outside. in this case,
Since the wireless card 4 is of a batteryless type, the transmission signal needs to transmit a transmission wave level at which the wireless card 4 can extract power and a clock by a transmission wave from the wireless card reader / writer 1. The modulated wave modulated and amplified by the transmission circuit 11 is radiated to the space via the loop antenna 2.

On the other hand, the modulated wave transmitted from the wireless card 4 is received by the loop antenna 2 of the wireless card reader / writer 1 and sent to the receiving circuit 12. The receiving circuit 12 obtains received data by performing processes such as filtering, amplification, and demodulation on the received signal. The obtained reception data is sent to the control circuit 13 and the control circuit 1
At 3, a predetermined process based on the received data is performed.

FIG. 3 shows an example of the basic configuration of the wireless card 4. In FIG. 3, reference numeral 21 denotes a power supply / clock extraction circuit, and reference numeral 22 denotes a transmission / reception circuit, to which the loop antenna 5 is connected. Reference numeral 23 denotes a control circuit for executing various processes, to which a power / clock extraction circuit 21 and a transmission / reception circuit 22 are connected.

The outline of the operation will be briefly described below. The modulated wave signal from the wireless card reader / writer 1 received by the loop antenna 5 is sent to a power / clock extraction circuit 21 where power is generated and a clock pulse is extracted and controlled. The signal is supplied to the circuit 23. On the other hand, the received modulated wave signal is also sent to the transmission / reception circuit 22, where it is demodulated to obtain demodulated data, and the control circuit 23 performs predetermined processing.

On the other hand, the transmission data created by the control circuit 23 is modulated by the transmission / reception circuit 22, sent to the loop antenna 5, and radiated into the space by the loop antenna 5.

Hereinafter, the loop antenna 2 used in the wireless card reader / writer 1 will be described. FIG. 4 shows a general example of a loop antenna. In FIG. 4, a loop antenna 31 is, for example, a loop antenna having three turns, and a matching circuit 32 is connected thereto. The matching circuit 32 is a circuit that performs a conversion between the bandwidth of the loop antenna 31 and impedance.
In the field of communication equipment, impedance matching is performed to 50Ω.

FIG. 5 shows an example of a pattern of the radiated electric field intensity generated by the loop antenna 31. 5, reference numeral 41 denotes a radiation pattern of a radiation field intensity main lobe, and reference numeral 42 denotes a radiation pattern of a side lobe. When, for example, an unmodulated wave having a frequency f0 is input from the signal generator 33, the general loop antenna 31 has a main lobe radiation pattern 41 and a side lobe radiation pattern. When the loop antenna 31 is installed in free space, a radiation pattern such as a radiation pattern 41 of a main lobe and a radiation pattern 42 of a side lobe is obtained. However, in a general wireless card system, radiation above the radiation pattern 41 of the main lobe is performed. Use patterns primarily.

FIG. 6 shows a communication area of a conventional wireless card system and a desired communication area of a future wireless card system, particularly a wireless card system which needs to secure a wide communication area such as an automatic ticket gate. . 6, reference numeral 51 denotes a loop antenna; 52, a radiation pattern of a main lobe; 53, a radiation pattern of a side lobe;
Is a communication area considered necessary for future wireless card systems. The hatched area 55 is the difference between the current communication area using the antenna and the communication area 54, and this may be a communication area where specifications are not reached in the future.

FIG. 7 schematically shows the configuration of the loop antenna according to the first embodiment. The loop antenna according to the first embodiment is a configuration example in which the above-mentioned non-specification communication area is reduced. In FIG.
Reference numeral 61 denotes a quarter-divided array antenna (loop antenna element), 62 denotes a combined loop antenna, and 63 denotes a driver in the transmission circuit.

Here, an example of a method of manufacturing the loop antenna 62 will be described. For example, a loop antenna element 6 may be formed such that one conductor is １ ／ of the desired antenna size.
It is created by winding in order so that four 1s can be formed. In this case, the winding direction is the direction of the arrow in FIG. The loop antenna 62 can realize not only four divisions but also n (1 <n: integer) divisions.

FIG. 8 shows the characteristics of the loop antenna 62. The current of each side of the quarter-divided array antenna, that is, the loop antenna element 61, is as shown by an arrow in FIG. The inner sides of the loop antenna element 61 cancel each other out, and the current flows only in the outermost circumference as a whole of the antenna. Therefore, the radiated electric field pattern is the same as the radiated electric field pattern radiated by the antenna in which the current flows only in the outermost periphery in the far field.

However, when the distance between antennas is short,
Since the geometric distance has an effect, the characteristics of the divided antenna appear. Reference numeral 71 indicates a radiation pattern when a current flows only in the outermost periphery. In other words, it is a radiated electric field pattern when a current is supplied to the loop antenna having the same size as the outermost circumference. Reference numeral 72 indicates a radiation pattern when a split antenna is used.

As a result, when the antenna structure shown in FIG. 7 is used, a communication area is improved, and at the same time, an antenna configuration in which the radiated electric field intensity does not change from the ordinary loop antenna in the far field is obtained.

FIG. 9 schematically shows the configuration of the loop antenna according to the second embodiment. The loop antenna according to the second embodiment is a configuration example in which the electric field strength only near the antenna is increased and the electric field strength is not increased in the far field. In FIG. 9, a loop antenna 81 has a second loop antenna 8 having an opening area smaller than the desired communication area inside a first loop antenna 82 having an opening area equal in size to the desired communication area.
3 are arranged. Reference numeral 84 denotes a driver in the transmission circuit.

FIG. 10 shows the distance characteristics of the radiated electric field strength depending on the opening area of the loop antenna 81. The first and second loop antennas 82 and 83 are caused to flow currents that generate the same radiated electric field strength in the far field, respectively.
The characteristic of the distance versus radiated electric field strength of the loop antenna 82 is as shown by a characteristic 91, and the characteristic of the distance vs. radiated electric field strength of the second loop antenna 83 is as shown by a characteristic 92. This indicates that the smaller the aperture area, the higher the radiated electric field intensity near the antenna. This is related to the geometric distance of the antenna.

FIG. 11 shows the combined radiated electric field strength characteristics of the characteristics 91 and 92 of FIG. In FIG. 11, the characteristic 10
Reference numeral 1 denotes a radiation electric field intensity pattern of the first loop antenna 82, characteristic 102 denotes a radiation electric field intensity pattern of the second loop antenna 83, and characteristic 103 denotes a combined radiation electric field intensity pattern. As a result, it is possible to improve only the electric field strength characteristics near the antenna.

FIG. 12 schematically shows a configuration of a loop antenna according to the third embodiment. The loop antenna according to the third embodiment is a configuration example in which the radiated electric field intensity near the antenna is improved. In FIG. 12, a loop antenna 111 is formed by stacking a plate-like magnetic body 113 such as a ferrite plate and a metal plate 114 such as a stainless steel plate behind a loop antenna 112 having an opening area corresponding to a desired communication area. Back member 115
Is arranged. Note that reference numeral 1164 denotes a driver in the transmission circuit.

FIG. 13 shows the loop antenna 111 of FIG.
The characteristics of A characteristic 121 indicates the distance versus the radiated electric field intensity characteristic of the loop antenna 112 alone, and a characteristic 122 indicates the distance versus the radiated electric field intensity characteristic of the loop antenna 111 in which the magnetic body 113 and the metal plate 114 are combined. Thereby, it is possible to improve the radiated electric field strength characteristics near the antenna. Further, by disposing the metal plate 114 at the back, it is possible to prevent external noise from entering the antenna and conversely prevent unnecessary radiation from the antenna to the circuit.

FIG. 14 schematically shows the configuration of the loop antenna according to the fourth embodiment. The loop antenna according to the fourth embodiment is a configuration example in which the measurement of the radiated electric field strength at a distance is stabilized. In FIG. 14, a loop antenna 131 is a twisted pair wire 132.
It is composed of One line 1 of the twisted pair line 132
One end of 33 is grounded and the other end is open.
Also, the other wire (core wire) 134 of the twisted pair wire 132
Is connected to ground, and the other end is connected to a driver 135 in the transmission circuit.
It is connected to the.

FIG. 15 shows the loop antenna 131 of FIG.
5 shows the distance characteristics of the radiated electric field strength of the radiator. Characteristic 141 is the radiation electric field intensity characteristic in the radiation direction, and 142 is the radiation electric field intensity in the tangential direction. The loop antenna 131 of FIG. 14 is effective when the distance of λ / 2π (λ = c / f0: speed of light) is 3
It is effective when m or less. That is, it is effective in the measurement of a weak radio station according to the Radio Law. At a distance of λ / 2π, εγ (normal direction radiated electric field intensity) and εθ
(Tangential radiated electric field strength). Since this has been proved in the electromagnetic engineering, the details are omitted.

Here, when the radiated electric field intensity is measured at a distance of λ / 2π, it is usually necessary to measure only εγ.
The subtle tilt of the antenna affects the εθ component. However, when the antenna structure shown in FIG. 14 is used, the influence of the εθ component is reduced, and unnecessary radiation is eliminated. That is, when viewed from the outside, it looks as if the radiated electric field has been reduced.

FIG. 16 schematically shows the configuration of the loop antenna according to the fifth embodiment. The loop antenna according to the fifth embodiment is a modification of the antenna configuration shown in FIG. In FIG. 16, loop antenna 1
51, a conductive tape 153 as a band-shaped conductor is arranged along the loop antenna 152 on the loop antenna 152 formed by an insulating wire so as to have an opening area corresponding to a desired communication area; A slit 154 is provided in the middle of the conductive tape 153 so as not to form a closed loop. One end of the conductive tape 153 and one end of the loop antenna 152 are grounded, and the other end of the loop antenna 152 is connected to a driver 155 in the transmission circuit. Here, it should be noted that the ground line does not necessarily form a closed loop.

FIG. 17 schematically shows a configuration of the loop antenna according to the sixth embodiment. The loop antenna according to the sixth embodiment shows another modification of the antenna configuration in FIG. In FIG. 17, a loop antenna 161 is constituted by a core 163 of a coaxial cable 162 so as to have an opening area corresponding to a desired communication area. One end of a core wire 163 of the coaxial cable 162 is grounded, and the other end is connected to a driver 165 in the transmission circuit. Also, the shielded wire 1 of the coaxial cable 162
The middle portion 64 is grounded, and both ends 166 and 167 of the shielded wire 164 of the coaxial cable 162 are open.

FIG. 18 schematically shows a configuration of the loop antenna according to the seventh embodiment. The loop antenna according to the seventh embodiment is a configuration example in which the efficiency is improved. In FIG. 18, the loop antenna 171
Is located inside a first loop antenna 172 having an opening area equal in size to the desired communication area, and a second loop antenna 173 having an opening area smaller than the desired communication area.
Are arranged. Then, a first tuning circuit 174 is connected between both ends of the first loop antenna 172, and a second tuning circuit 175 is connected between both ends of the second loop antenna 173. Reference numeral 176 denotes a driver in the transmission circuit.

FIG. 19 shows the loop antenna 171 of FIG.
2 shows an equivalent circuit of FIG. The first and second loop antennas 172 and 173 have mutual inductance M
And form a double-tuned circuit. This allows
The Q of the antenna of the first and second tuning circuits 174 and 175 can be set high, and an efficient antenna configuration can be realized.

The mutual inductance M is adjusted by an element which is difficult to adjust, for example, a capacitor.
Generally, when a double-tuned circuit is used for an antenna, one of the circuits is often constituted by circuit elements. However, as shown in FIG. 18, when two antennas are used, a radio wave can be received by the two antennas, and the reception sensitivity is higher than that by one antenna.

FIG. 20 shows the loop antenna 171 of FIG.
2 shows the frequency characteristics of FIG. The characteristic 181 indicates the frequency characteristic of the first loop antenna 172, the characteristic 182 indicates the frequency characteristic of the second loop antenna 173, and the characteristic 183 indicates the overall characteristic. As a result, the Q of each antenna can be set high, and an antenna with high overall sensitivity can be formed.

[0053]

As described above in detail, according to the present invention, it is possible to provide a loop antenna and an information processing apparatus capable of solving the problems of the communication area and the problem of the Radio Law, which are the conventional problems.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing a configuration of a wireless card system.

FIG. 2 is a block diagram showing an example of a basic configuration of a wireless card reader / writer.

FIG. 3 is a block diagram illustrating an example of a basic configuration of a wireless card.

FIG. 4 is a schematic configuration diagram schematically showing a general example of a loop antenna.

FIG. 5 is a diagram showing an example of a radiated electric field intensity pattern generated by the loop antenna of FIG. 4;

FIG. 6 is a diagram showing a communication area of a conventional wireless card system and a desired communication area of a future wireless card system.

FIG. 7 is a schematic configuration diagram schematically showing the configuration of the loop antenna according to the first embodiment.

FIG. 8 is a diagram showing characteristics of the loop antenna of FIG. 7;

FIG. 9 is a schematic configuration diagram schematically illustrating a configuration of a loop antenna according to a second embodiment.

FIG. 10 is a view showing a distance characteristic of a radiated electric field intensity depending on an opening area of the loop antenna of FIG. 9;

FIG. 11 is a view showing a combined radiated electric field strength characteristic of the characteristic of FIG. 10;

FIG. 12 is a schematic configuration diagram schematically showing a configuration of a loop antenna according to a third embodiment.

FIG. 13 is a view showing characteristics of the loop antenna of FIG. 12;

FIG. 14 is a schematic configuration diagram schematically showing a configuration of a loop antenna according to a fourth embodiment.

FIG. 15 is a view showing a distance characteristic of a radiated electric field intensity of the loop antenna of FIG. 14;

FIG. 16 is a schematic configuration diagram schematically showing a configuration of a loop antenna according to a fifth embodiment.

FIG. 17 is a schematic configuration diagram schematically illustrating a configuration of a loop antenna according to a sixth embodiment.

FIG. 18 is a schematic configuration diagram schematically showing a configuration of a loop antenna according to a seventh embodiment.

19 is a circuit diagram showing an equivalent circuit of the loop antenna shown in FIG.

FIG. 20 is a diagram illustrating frequency characteristics of the loop antenna of FIG. 18;

[Explanation of symbols]

1. wireless card reader / writer (information processing device), 2.
...... Loop antenna, 3 ... host device, 4 ... wireless card (wireless communication medium), 5 ... loop antenna, 6 ... integrated circuit, 61 ... array antenna (loop antenna element), 62 ... loop antenna 81, a loop antenna, 82, a first loop antenna, 83, a second loop antenna, 111, a loop antenna, 112
Loop antenna, 113: magnetic body, 114: metal plate, 115: rear member, 131: loop antenna,
132 ... twisted pair wire, 151 ... loop antenna, 152 ... loop antenna, 153 ... conductive tape (band-shaped conductor), 154 ... slit, 161 ... loop antenna, 162 ... coaxial cable, 171 ... loop Antenna, 172... First loop antenna, 173
... Second loop antenna, 174... First tuning circuit, 175... Second tuning circuit.

Claims (16)

[Claims] 1. An opening area of a desired loop antenna is n
The present invention is characterized in that an opening area of the desired loop antenna is realized by combining n loop antenna elements having an area divided into (n: integer), and this is constituted by one conductor. And loop antenna. 2. A second loop antenna having an opening area smaller than the communication area is disposed inside a first loop antenna having an opening area corresponding to a desired communication area. A loop antenna characterized in that a predetermined radiated electric field strength is obtained by a combined radiated electric field strength of a large first loop antenna and a second loop antenna having a small opening area. 3. A loop comprising a loop antenna having an opening area corresponding to a desired communication area, and a back member formed by laminating a plate-shaped magnetic body and a metal plate behind the loop antenna. antenna. 4. A loop antenna, wherein a conductor is provided around a loop antenna having an opening area corresponding to a desired communication area, and the conductor is grounded. 5. A twisted pair wire, wherein one end of one conductor of the twisted pair wire is used as an input end and the other end is grounded, and one end of the other conductor of the twisted pair wire is grounded and the other end is grounded. A loop antenna which is open. 6. A band-shaped conductor is arranged on a loop antenna having an opening area corresponding to a desired communication area along the loop antenna, and a slit is formed in a middle portion of the conductor so as not to form a closed loop. Wherein the conductor is grounded. 7. A coaxial cable, wherein one end of a core wire of the coaxial cable is an input end and the other end is grounded, and one end of a shielded wire of the coaxial cable is grounded and the other end is opened. A loop antenna, comprising: 8. A desired band is ensured by adjusting first and second loop antennas resonating with each other, and adjusting the band of the first and second loop antennas and the coupling between the antennas. A loop antenna comprising: 9. A desired loop antenna opening area is defined as n
A loop antenna having a desired loop antenna opening area realized by combining n loop antenna elements having an area divided into (n: integer), and having a single conductor. Wireless communication means for performing wireless transmission / reception to / from an external wireless communication medium via the loop antenna; and processing means for performing predetermined information processing based on a result of transmission / reception by the wireless communication means. Characteristic information processing device. 10. A second loop antenna having an opening area smaller than the communication area inside a first loop antenna having an opening area corresponding to a desired communication area. A loop antenna configured to obtain a predetermined radiated electric field strength by a combined radiated electric field strength of a large first loop antenna and a second loop antenna having a small opening area; and an external wireless communication medium via the loop antenna. An information processing apparatus, comprising: a wireless communication unit that performs wireless transmission and reception between the wireless communication unit and a processing unit that performs predetermined information processing based on a result of transmission and reception by the wireless communication unit. 11. A loop antenna comprising a loop antenna having an opening area corresponding to a desired communication area, and a back member formed by laminating a plate-shaped magnetic body and a metal plate behind the loop antenna. Information characterized by comprising: wireless communication means for transmitting and receiving wirelessly to and from an external wireless communication medium via an antenna; and processing means for performing predetermined information processing based on a result of transmission and reception by the wireless communication means. Processing equipment. 12. A loop antenna having a conductor disposed around a loop antenna having an opening area corresponding to a desired communication area and grounding the conductor, and an external wireless communication medium via the loop antenna. An information processing apparatus, comprising: a wireless communication unit that performs wireless transmission and reception between the wireless communication unit and a processing unit that performs predetermined information processing based on a result of transmission and reception by the wireless communication unit. 13. A twisted pair wire, wherein one end of one conductor of the twisted pair wire is an input end and the other end is grounded, and one end of the other conductor of the twisted pair wire is grounded and the other end is grounded. A loop antenna in an open state, wireless communication means for wirelessly transmitting and receiving to and from an external wireless communication medium via the loop antenna, and processing for performing predetermined information processing based on a result of transmission and reception by the wireless communication means Means, and an information processing apparatus characterized by comprising: 14. A band-shaped conductor is arranged on a loop antenna having an opening area corresponding to a desired communication area along the loop antenna, and a slit is formed in a middle portion of the conductor so as not to form a closed loop. , And
A loop antenna having the conductor grounded; a wireless communication unit for performing wireless transmission / reception with an external wireless communication medium via the loop antenna; and performing predetermined information processing based on a result of transmission / reception by the wireless communication unit. An information processing apparatus comprising: 15. A coaxial cable, wherein one end of a core wire of the coaxial cable is set as an input end and the other end is grounded, and one end of a shielded wire of the coaxial cable is grounded and the other end is opened. A loop antenna, a wireless communication unit for performing wireless transmission and reception with an external wireless communication medium via the loop antenna, a processing unit for performing predetermined information processing based on a transmission and reception result by the wireless communication unit, An information processing apparatus characterized by comprising: 16. The first and second loop antennas, each of which resonates, wherein the first and second loop antennas
A loop antenna configured to secure a desired band by adjusting the band of the loop antenna and the coupling between the antennas, and a wireless communication between an external wireless communication medium through the loop antenna. An information processing apparatus comprising: wireless communication means for performing transmission and reception; and processing means for performing predetermined information processing based on a result of transmission and reception by the wireless communication means.