JP3870888B2 - Wireless communication card - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wireless communication card applied to a wireless LAN.
[0002]
[Prior art]
Recently, wireless LAN (Wireless Local Area Network) has been widely used due to higher transmission speed and lower price. The wireless LAN can be used indoors and outdoors. In offices, homes, and the like, a wireless LAN network is constructed by an access point (also referred to as a wireless base station) and a plurality of personal computers each equipped with a wireless LAN card. Outdoors, access points are installed in highly public stations, airports, hotel lobbies, fast food restaurants, etc., and portable personal computers (so-called notebook personal computers, hereinafter abbreviated as portable PCs). ), Public wireless LAN services (so-called hot spots) that use information terminal devices such as PDA (Personal Digital Assistants), and FWA (Fixed Wireless Access) services for residences and apartments It becomes possible.
[0003]
The wireless LAN system currently on the market mainly uses the ISM (Industrial Scientific & Medical) band (2.4 GHz band) and is compliant with IEEE802.11b with a transmission speed of 11 Mbps (bits / second). is there. Furthermore, the 5 GHz band wireless LAN system has been institutionalized for indoor use, and a product of 5 GHz band wireless LAN system compliant with IEEE802.11a with a communication speed of 36 Mbps-54 Mbps is also on the market.
[0004]
The indoor 5 GHz band is a frequency band of 5.15-5.25 GHz. Furthermore, the 5 GHz band will be opened to the outdoor wireless LAN in the near future. As a result, high-speed wireless LAN can be used not only indoors but also outdoors, and public wireless LAN services are expected to expand rapidly. It is planned to be opened for outdoor use in the bands of 4.9-5 GHz and 5.03-5.09 GHz, 20 MHz per channel, 7 channels can be arranged in both bands, 20 Mbps The above transmission speed is possible.
[0005]
However, when the wireless LAN is used outdoors, since the hot spot is a specific place, the user must always check the service area, and there is a problem in usability. On the other hand, when a portable PC or the like is used in a wide-area mobile environment, it is easy to use a PC card compatible with PHS (Personal Handyphone System), which is relatively inexpensive. However, in the case of PHS, the communication speed is 32 kbps to 128 kbps, which is insufficient for broadband communication.
[0006]
Thus, the high-speed communication service in a limited area by wireless LAN and the low-speed communication service in a wide area by PHS had a complementary relationship. Therefore, it is preferable that both services can be switched by user selection or automatically. For example, a high-speed wireless LAN is used in the indoor and outdoor access point areas, and PHS is used outside the access point area.
[0007]
FIG. 1 shows an overview of a conventional Internet access method in which a user can receive both a wireless LAN service and a PHS service. Reference numeral 100 indicates a portable PC, and the portable PC includes a PC card slot. Reference numeral 101 denotes a wireless LAN card compatible with a card bus that is used by being inserted into a card slot of the PC 100, and has a wireless LAN standard such as IEEE802.11a, IEEE802.11b, IEEE802.11g, or the like.
[0008]
The PC card is a PC card standard jointly established by the US PCMCIA (Personal Memory Card International Association) and JEIDA (Japan Electronics Industry Promotion Association). Most portable PCs have a PC card slot. Yes. The standard defines a card bus that realizes a 32-bit data transfer rate equivalent to the PCI bus.
[0009]
In FIG. 5, reference numeral 102 indicates a wireless LAN access point (base station), and is connected to the Internet 104 via an optical or DSL (Digital Subscriber Line) network 103. A user can access the Internet using the portable PC 100 in a service area of an access point such as a hot spot.
[0010]
Reference numeral 105 denotes a card bus compatible PHS card that is used by being inserted into the card slot of the PC 100. In general, a device conforming to a transmission protocol using PHS called PIAFS (PHS Internet Access Forum Standard) is used. Reference numeral 106 denotes a PHS base station, which is connected to the Internet 104 via a PHS network 107 that borrows an ISDN (Integrated Services Digital Network) network.
[0011]
In the conventional system shown in FIG. 5, the user carries the wireless LAN card 101 and the PHS card 105, and in a hot spot, the wireless LAN card 101 is inserted into the card slot of the PC 100. Otherwise, the PHS card 105 is inserted into the PC 100. It was inserted into the card slot. As described above, in order for the user to receive both the wireless LAN service and the PHS service, it is necessary to carry the PC cards 101 and 105 corresponding to the two services, which is troublesome. In order to solve this problem, it is described in Patent Document 1 below that a PHS communication module and a LAN communication module are configured in one PC card.
[0012]
[Patent Document 1]
JP 2001- 28614 A
[Problems to be solved by the invention]
By the thing of this patent document 1, the trouble of carrying around two PC cards or replacing a PC card can be eliminated. However, since PHS is positioned as public wireless communication, only a limited number of people can provide a PHS card, which is one of the devices for PHS. Production and sales were restricted. Therefore, if a PHS card that can be actually obtained can be used as it is, an advantage that it is not necessary to manufacture the PHS card can be obtained. In addition, when there are a plurality of public PHS providers such as NTT Docomo and DDI pocket in Japan, not all providers provide communication cards as described in Patent Document 1, There is a problem that the user is restricted in selecting a business operator.
[0014]
Therefore, an object of the present invention is to provide a wireless communication card that is currently provided and can use a plurality of communication methods such as a wireless LAN and a PHS by using an available public wireless communication card as it is. There is.
[0015]
[Means for Solving the Problems]
To solve the above problems, this invention provides the mounting removable radio communication card to the information terminal device,
A first interface unit for performing physical and logical connection to the information terminal device;
A second interface unit that performs physical and logical connection to a public wireless communication card that can be attached to and removed from the wireless communication card;
A wireless LAN unit for communication with a wireless LAN access point;
An interface conversion unit for converting the second interface portion of the interface to the first interface portion of the interface,
A switching unit that selectively connects the wireless LAN unit and the interface conversion unit to the first interface unit;
And a control unit that controls the switching unit.
[0016]
In this invention, it is possible to easily realize a wireless communication card having two functions of a wireless LAN and a wide area mobile communication by directly using a public communication card or a public communication module provided by a business operator. In addition, it is not necessary to carry two cards, and a wireless seamless connection can be realized outdoors or indoors. Further, there is no need to newly design and manufacture a communication card for mobile communication. Furthermore, since the communication card has a separate configuration, it is possible to flexibly cope with changes in specifications and standards of each communication method. Furthermore, when there are a plurality of public mobile communication operators, the user can arbitrarily select the operator.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described. In FIG. 1, reference numeral 200 indicates a wireless LAN card according to the present invention. The wireless LAN card 200 is a wireless LAN card compatible with a card bus that is inserted into a card slot of a PC and uses wireless LAN standards such as IEEE802.11a, IEEE802.11b, and IEEE802.11g. The wireless LAN card 200 has an antenna 201 and is inserted into one end of the PC card slot.
[0018]
An IEEE802.11 hierarchical structure can be made to correspond to the OSI reference model. The OSI reference model has a seven-layer hierarchical structure from the lowest physical layer to the highest application layer. For example, the type of frequency band to be used, the band per channel, the modulation method (for example, spread spectrum method), encoding and decoding for error correction, and the like are included in the physical layer.
[0019]
The upper layer of the physical layer is called a link layer. The link layer includes a media access control layer (MAC). The function of the medium access control layer (MAC) is to control and manage timing related to packet communication in the wireless LAN system and multiple access. For example, a CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) scheme is included in the medium access control layer (MAC). The medium access control layer (MAC) constitutes a sublayer of the data link layer. The other sublayer is an LLC (Logical Link Control) layer. A description of the upper layer of the link layer is omitted. Standards such as IEEE802.11a, IEEE802.11b, and IEEE802.11g indicate different standards in the physical layer.
[0020]
Reference numeral 210 is a PHS card sold by a business operator. In one embodiment, the PHS card 210 is a CompactFlash® card. The compact flash card was originally developed in the United States, and at present, a standardization organization called CompactFlash Association has been established, and the standard is determined there. Many commercially available PHS cards are compact flash cards. The PHS card 210 has an antenna 211, and a connection terminal is provided at one end 212 thereof. An antenna may be built in.
[0021]
The wireless LAN card 200 has a storage unit 203 for the PHS card 210. A compact flash slot 204 is provided in the storage unit 203. 1A, the PHS card 210 is slid from the one end 212 side and inserted into the storage unit 203, and the PHS card 210 is inserted into the compact flash slot 204. FIG. 1B shows a state where the PHS card 210 is inserted into the wireless LAN card 200.
[0022]
In this way, the wireless LAN card 200 with the PHS card 210 inserted is appropriately called a wireless LAN / PHS card. The wireless LAN / PHS card shown in FIG. 1B is in the form of one PC card, has two wireless communication functions of wireless LAN and PHS, and is a business related to PHS which is a public wireless communication function. It is possible to use a commercially available PHS card as it is. Note that power is supplied from the PC 300 to the wireless LAN card 200 and the PC card 210 via the PC card interface unit 304.
[0023]
FIG. 2 shows a circuit configuration of the wireless LAN / PHS card, in particular, a circuit configuration built in the wireless LAN card 200. Reference numeral 300 indicates a portable PC. The PHS card 210 has a circuit configuration capable of performing data communication using a protocol conforming to PIAFS, similar to a commercially available card.
[0024]
The wireless LAN card 200 includes a wireless LAN unit 303, a PC card interface unit 304, a switching unit 305, an interface conversion unit 306, a compact flash interface unit 307, a control unit 308, a switch unit 309, and a display unit 310. It is composed of The PC card interface 304 and the compact flash interface unit 307 include physical and logical interfaces such as a card slot and a card bus.
[0025]
The wireless LAN unit 303 includes an RF circuit connected to the antenna 201, a modulation circuit such as OFDM (Orthogonal Frequency Division Multiplex), a MAC processing circuit, and a baseband processing circuit. The wireless LAN unit 303 has an IEEE802.11a configuration, for example. Other standards such as IEEE802.11b, IEEE802.11g, etc., or a structure that can support a plurality of standards may be used. Data is input and output between the wireless LAN unit 303 and the switching unit 305. The switching unit 305 has a function of switching a data path.
[0026]
The PC card interface unit 304 connected to the switching unit 305 has a function of interfacing with the PC 300 via, for example, a card bus. The PC card interface unit 304 is commonly used for the wireless LAN and the PHS.
[0027]
The compact flash interface unit 307 is a part that interfaces with the PHS compact flash card 210. An interface conversion unit 306 is connected to the compact flash interface unit 307. The interface conversion unit 306 has a function of converting a compact flash interface into a PC card interface.
[0028]
The control unit 308 controls the entire wireless LAN card 200, and mainly generates a control signal that designates the communication method as one of the wireless LAN and the PHS, and controls the switching unit 305 by the control signal. A switch unit 309 is connected to the control unit 308. The switch unit 309 is a switch that is manually operated by the user, and is, for example, a slide switch provided on the side surface of the wireless LAN card 200. The user operates the switch unit 309 to switch between a state (mode) in which the wireless LAN is used and a state (mode) in which the PHS is used. Without providing the switch unit 309, the driver software on the PC 300 side sends an instruction to select which communication method to the control unit 308 via the PC card interface unit 304, and the control unit 308 follows the instruction. The switching unit 305 may be controlled.
[0029]
Further, the communication method may be automatically switched. As a method of automatic switching, a method of selecting a side that can normally communicate by switching alternately between the wireless LAN and the PHS with a relatively long period is possible. For example, it is detected whether it is within the service area of the wireless LAN access point at the current location, and if it is not within the service area of the wireless LAN, it is detected whether it is within the service area of the PHS. The communication method is automatically switched based on the result. In consideration of the data rate or communication cost, it is set which of the wireless LAN and PHS is prioritized.
[0030]
The display unit 310 connected to the control unit 308 is provided, for example, on the side surface of the wireless LAN card 200, and is composed of a light emitting diode that can be seen even when the wireless LAN card 200 is inserted into the card slot of the PC 300. Display unit 310 causes, for example, a red light emitting diode to emit light when an access point can receive a beacon signal generated at a constant time interval when a wireless LAN is set. Further, when the PHS is set, the downlink control signal of the base station of the PHS can be received, and the green light emitting diode is caused to emit light when in the service area (in the service area). Thereby, the user can know which communication method is available.
[0031]
FIG. 3 illustrates an Internet access method in which a user can receive both a wireless LAN service and a PHS service using a wireless LAN / PHS card in which the PHS compact flash card 210 is mounted on the wireless LAN card 200. The outline of is shown. Reference numeral 401 indicates the wireless LAN / PHS card according to the embodiment of the present invention described above. The wireless LAN / PHS card 401 is inserted into the card slot of the portable PC 300.
[0032]
When a user uses a wireless LAN at a hot spot or the like, the user communicates wirelessly with a wireless LAN access point (base station) 402 and accesses the Internet 404 via an optical or DSL network 403. When PHS is used, the Internet 404 is accessed through the PHS base station 405 and the PHS network 406 that borrows the ISDN network. As described above, the user can receive both the wireless LAN service and the PHS service while the wireless LAN / PHS card 401 according to the present invention is inserted into the card slot of the PC 300, and it is necessary to carry two cards. There is no.
[0033]
Next, another embodiment of the present invention will be described with reference to FIGS. 4A and 4B. Reference numeral 500 indicates a PDA. The PDA 500 is a flat plate of the size of a palm, and is provided with a liquid crystal display unit 510 that also serves as an input screen that can be input with a stylus, operation buttons 511, and the like. The PDA 500 has a built-in CPU and operates with a predetermined OS. An address book, a schedule, browser software, mail software, game software, word processing software, spreadsheet software, utility software for a compact flash card, utility for a PHS module Software etc. are attached.
[0034]
A compact flash card slot is provided on the upper end surface of the PDA 500. A compact flash type wireless LAN card 501 can be inserted into this slot. The wireless LAN card 501 is based on a compact flash card standard in terms of physical shape, interface, and the like, and has an antenna and a circuit unit for wireless LAN communication built in the card.
[0035]
Further, the wireless LAN card 501 includes a card slot into which a card of another standard different from the compact flash, for example, a PHS module 502 of a memory card standard smaller than itself can be mounted. As a standard for the PHS module 502, a memory card such as a memory stick (product name) or an SD card can be used. The PHS module 502 has a function as a communication card for PHS and is provided by a PHS provider. Incorporation of the PHS communication function into the card-like PHS module 502 is relatively easy if the size reduction can be solved by a method such as LSI conversion of the circuit portion.
[0036]
4A shows the PDA 500, the compact flash type wireless LAN card 501 and the PHS module 502 separately, and FIG. 4B shows the state where the wireless LAN card 501 with the PHS module 502 installed is inserted into the compact flash card slot of the PDA 500. Indicates. In the state of FIG. 4B, the wireless communication of the selected side between the wireless LAN and the PHS can be performed as in the above-described embodiment. The circuit configuration inside the compact flash type wireless LAN card 501 is the same as that described with reference to FIG. 2, but the compact flash interface unit 307 is changed to the standard interface of the card of the PHS module 502, It is necessary to change the PC card interface unit 304 to a compact flash interface unit.
[0037]
The present invention is not limited to one embodiment and other embodiments of the present invention described above, and various modifications and applications can be made without departing from the gist of the present invention. For example, other than PHS, for example, PDC (Personal Digital Cellur), cdma (Code Division Multiple Access) -One, W-CDMA (Wideband-Code Division Multiple Access) can be used as a wide area mobile communication function. is there. As the information terminal device using the wireless communication card according to the present invention, a device other than a PC or PDA, for example, a game device can be used.
[0038]
【The invention's effect】
As is apparent from the above description, according to the present invention, a public communication card or a public communication module provided by a mobile communication operator is used as it is, and two types of wireless LAN and wide area mobile communication are used. A wireless communication card having a function can be easily realized, it is not necessary to carry two cards, and a wireless seamless connection outdoors or indoors can be realized. In addition, since a public communication card or a public communication module provided by a mobile communication provider may be used as it is, it is not necessary to newly design and manufacture a communication card for mobile communication. Furthermore, since the communication card has a separate configuration, it is possible to flexibly cope with changes in specifications and standards of each communication method. Furthermore, when there are a plurality of public mobile communication operators, the user can arbitrarily select the operator.
[Brief description of the drawings]
FIG. 1 is a schematic diagram for explaining a method for accessing the Internet according to an embodiment of a wireless LAN / PHS card according to the present invention;
FIG. 2 is a block diagram showing a circuit configuration of an embodiment of the present invention.
FIG. 3 is a schematic diagram for explaining a case where a portable PC using one embodiment of the present invention is connected to the Internet.
FIG. 4 is a schematic diagram showing another embodiment of the present invention.
FIG. 5 is a schematic diagram for explaining a method for accessing the Internet by one of a conventional wireless LAN and PHS.
[Explanation of symbols]
200 ... Wireless LAN card, 210 ... Compact flash type PHS card, 300 ... Portable PC, 303 ... Wireless LAN unit, 304 ... PC card interface unit, 305 ... Switching unit 306 ... Interface conversion unit 307 ... Compact flash interface unit 308 ... Control unit 500 ... PDA 501 ... Compact flash wireless LAN card 502 ... PHS module

Claims (7)

In a wireless communication card that can be attached to and removed from an information terminal device,
A first interface unit for performing physical and logical connection to the information terminal device;
A second interface unit that performs physical and logical connection to a public wireless communication card that can be attached to and removed from the wireless communication card;
A wireless LAN unit for communication with a wireless LAN access point;
An interface conversion unit for converting the second interface portion of the interface to the first interface unit interface,
A switching unit that selectively connects the wireless LAN unit and the interface conversion unit to the first interface unit;
A wireless communication card comprising: a control unit that controls the switching unit. Wireless communication card according to claim 1, wherein the upper Symbol controller is designed to control the switching unit based on an instruction from the information terminal device. Et al, a switch unit is,
Wireless communication card according to claim 1, wherein said control unit controls the upper SL switch unit based on the instruction generated in response to the operation of the switch unit. As above Symbol controller automatically selects a wireless LAN and public system wireless communication, the wireless communication card according to claim 1, wherein so as to control the switching unit. Et al, a display unit of,
The wireless communication card according to claim 1 , wherein the control unit controls the display unit so that the display unit displays whether or not wireless LAN and public wireless communication can be used. Upper Symbol first interface is a PC card interface, the second interface is a wireless communication card according to claim 1 wherein the card interface for a small card from the PC card. First interface on SL is card interface for a small card from the PC card, the second interface according to claim 1, wherein a further card interface of a small public system radio communication card of the memory card standard radio Communication card.

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