Communication device communication method, and communication terminal device

A radio communication CPU controls each section of a radio communication device included in a short distance radio communication network by using network setting information in a network setting storage section. A connection relation with a communication network (for example, the Internet) is set and transmission/reception of data to/from equipment included in the communication network via the short distance radio communication network is controlled. Thus, the network setting or the like for connecting to the Internet or the like is simplified for each portable equipment existing in the short distance radio communication network.

TECHNICAL FIELD

This invention relates to a communication device, a communication method, and a communication terminal device which are suitable for a wireless LAN (local area network) system employing, for example, the Bluetooth system.

BACKGROUND ART

Recently, in the field of wireless LAN (local area network) system, there has been developed a system which employs the Bluetooth system for carrying out processing in conformity with the frequency hopping system using a radio wave of a band of 2.4 GHz and carrying out transmission/reception of data between equipments.

The Bluetooth system is a system for realizing ad hoc radio (RF) networking between a plurality of personal computers and devices, which is being cooperatively developed by corporations of various industries such as computers, telecommunication, networking and so on, utilizing the radio communication technology. The Bluetooth system was planned by the Bluetooth SIG (Special Interest Group) in which the following corporations have taken part: Intel, Ericsson, IBM, Nokia, and Toshiba (trademark registered). The Bluetooth system enables a notebook computer, a PDA (personal digital assistant), or a portable telephone to share information and various services with a personal computer through radio communications, and makes troublesome cable connection unnecessary. Such Bluetooth system is disclosed in “Bluetooth (TM) Special Interest Group, Bluetooth specification version 1.0”.

Since the Bluetooth system is designed for ad hoc short distance connection, a standard communication range is within 10 m. According to the Bluetooth system, a “piconet” with the maximum number of connected devices equal to 8 and the communication range of 10 m is constructed by carrying out ad hoc multi-point connection, and a bandwidth of 1 Mbps is shared. In carrying out synchronous communication in accordance with the Bluetooth system, a transfer rate of 432.6 Kbps can be realized for both up communication and down communication, and therefore a rate approximately 10 times that of ordinary analog connection using a 56 K modem can be realized. On the other hand, in asynchronous communication in accordance with the Bluetooth system, communication at a higher speed is possible, and 721 Kbps for down communication and 57.6 Kbps for up communication are realized. Furthermore, the Bluetooth system also supports audio communication and enables setting of a maximum of 3 synchronous audio channels (at a transfer rate of 64 Kbps) at the same time. Simultaneous transfer of audio and data can be realized in one channel which provides a 64-Kbps synchronous audio link and an asynchronous data link. Such Bluetooth system can be used on various types of platforms and can realize radio communication at a low cost.

According to such Bluetooth system, an intelligent mechanism held by PC-based software can be realized in all kinds of electronic equipments. However, to realize practical application of the Bluetooth system, it is necessary to realize miniaturization and reduction in cost of transceiver components so as to incorporate them into the current notebook personal computers, PDA, portable telephones, portable head sets or the like. Since portable equipments normally use batteries, it is necessary to reduce the dissipation power.

In order to solve these problems, the Bluetooth system employs a system for compactly designing all logics and transceiver hardware. The transceiver hardware uses a radio frequency in a band of 2.4 GHz that can be used without permission and employs a diffusion system based on frequency hopping in order to prevent wire tapping and interference. In this frequency hopping, hopping is carried out 1600 times per second on 79 channels obtained by splitting the band every 1 MHZ (2.402 to 2.480 GHz). Also, according to the Bluetooth system, data is encrypted and devices that can access data are limited by password authorization, in order to improve the security of data transmission.

In a wireless LAN system1100employing the Bluetooth system as described above, wireless LAN modules1110of the Bluetooth system are mounted on a portable telephone1101, a personal computer1102, a digital camera1103, and a portable information terminal1104, respectively, as shown inFIG. 31. Thus, the portable telephone1101, the personal computer1102, the digital camera1103and the portable information terminal1104constituting the wireless LAN system1100can carry out transmission/reception of data between one another by carrying out transmission/reception of data using their respective wireless LAN modules1110.

When connecting from the portable telephone1101of the wireless LAN system1100to the Internet1300via a mobile communication network1200by dial-up access, an Internet service provider1301in the Internet1300is accessed by the personal computer1102, the digital camera1103or the portable information terminal1104via the wireless LAN system1100and the mobile communication network1200, and connection to a WWW (world wide web) server1302in the Internet1300is made.

In this manner, with the wireless LAN system1100, the personal computer1102, the digital camera1103and the portable information terminal1104can be connected to the Internet1300through radio connection without having wired connection with the portable telephone1101. Therefore, with the wireless LAN system1100, the portability of the personal computer1102, the digital camera1103and the portable information terminal1104can be improved. Also, with such wireless LAN system1100, it is possible to connect to the Internet1300in the state where the user has the portable telephone1101in his/her bag and only carries a terminal such as the portable information terminal1104in hand.

The structure of a host equipment1500constituting the wireless LAN system1100will now be described with reference toFIG. 32. The host equipment1500is equivalent to an equipment operated by the user of the personal computer1102, the digital camera1103or the portable information terminal1104ofFIG. 31.

The host equipment1500is constituted by a communication control section1510which controls communication with the outside and is equivalent to the wireless LAN module1110, and a host control section1530for controlling the equipment itself.

The communication control section1510has a radio communication unit1511for controlling radio communication within the wireless LAN system1100, an antenna section1512for carrying out transmission/reception of data to/from each section constituting the wireless LAN system1100, a base band control section1513for giving a hopping frequency pattern to the radio communication unit1511, and an interface section1514for carrying out input/output of data with the host control section1530.

The base band control section1513carries out modulation and demodulation processing of frequency hopping, processing for converting data handled in the communication control section1510into a predetermined format and transmitting the data via the communication control section1510, and data conversion for converting the data received in the predetermined format and outputting the data to the host control section1530.

The radio communication unit1511has a receiving section1521for carrying out processing for receiving data from the antenna section1512, a transmitting section1522for carrying out processing for transmitting data from the antenna section1512, a switch section1523for switching transmission of data from the transmitting section1522via the antenna section1512and output of data from the antenna section1512to the receiving section1521, and a hopping synthesizer section1524for carrying out spectrum spreading based on frequency hopping with respect to the data in the receiving section1521and the transmitting section1522.

Moreover, the communication control section1510has a RAM (random access memory)1516, a ROM (read only memory)1517, and a radio communication CPU (central processing unit)1518which are connected to a data bus1515.

The radio communication CPU1518reads a control program for controlling each section constituting the communication control section1510from the ROM1517via the data bus1515, thus generating a control signal. In this case, the radio communication CPU1518houses data into the RAM1516as a work space when necessary, and executes the control program. Thus, the radio communication CPU1518controls the base band control section1513and the radio communication unit1511so as to control communication with another equipment constituting the wireless LAN system1100, and also controls the host control section1530via the interface section1514.

The host control section1530in the host equipment1500has an interface section1531for carrying out input/output of signals with the interface section1514of the communication control section1510. In the host control section1530, a network setting storage section1533for storing network setting information such as the server address of the Internet service provider1301when the host equipment1500is connected to the Internet, an individual information storage section1534for storing individual information such as the mail address, password and the like of each user held by each host equipment1500, and a CPU1535for controlling these sections are connected via a data bus1532.

In such host equipment1500, when connecting to the Internet1300, first, the network setting information stored in the network setting storage section1533and the individual information stored in the individual information storage section1534are outputted to the communication control section1510, and then, the radio communication unit1511and the base band control section1513are controlled so that connection setting with the Internet1300is carried out by the radio communication CPU1518of the communication control section1510using the network setting information and the individual information, thus establishing connection between the host equipment1500and the WWW server1302.

To add the wireless LAN function of the Bluetooth system to each equipment, two techniques are considered. The first technique is to provide the wireless LAN function as a built-in function in the equipment, and the second technique is to store the wireless LAN function of the Bluetooth system on a PCMCIA (Personal Computer Memory Card International Association) card and connect it to another equipment.

FIG. 33shows protocol stacks1610,1620mounted on the portable telephone1101and the portable information terminal1104in connecting to the Internet1300by using the wireless LAN system1100having the wireless LAN function of the built-in type according to the first technique.

On the layer above the LLC of the protocol stack1620, PPP (point to point protocol) is mounted, having a protocol necessary for dial-up access to the Internet1300. On the layers above the PPP, IP (Internet protocol) and TCP (transmission control protocol) necessary for connection to the Internet1300are mounted, and an application layer (AP) for preparation of user data is further mounted.

In the protocol stack1610, the protocols for realizing the Bluetooth system are mounted as the lower three layers similar to those of the protocol stack1620, and a layer for using the mobile communication network such as W-CDMA (wide band-code division multiple access) or the like is mounted thereon, thus setting a data communication mode to realize connection to the Internet1300via the mobile communication network1200.

FIG. 34shows protocol stacks1610,1630, and1640mounted on the portable telephone1101, the PCMCIA card1105, and the portable information terminal1104in storing the wireless LAN function onto the PCMCIA card to realize the wireless LAN system1100according to the second technique.

The wireless LAN function for constructing the wireless LAN system1100of the Bluetooth system is built in the PCMCIA card1105, and a physical layer (PHY), a medium access control layer (MAC) and a logical link control layer (LLC) for realizing the Bluetooth system are provided as lower three layers, similarly to the protocol stack1610of the portable telephone1101. In the protocol stack1630of the PCMCIA card1105, PCMCIA I/F is mounted as the upper layer above the LLC.

In the protocol stack1640of the portable information terminal1104, PPP, IP, and TCP are mounted as the upper layers above the PCMCIA I/F layer, and AP and transmission/reception of user data are provided as the uppermost layer.

However, the first technique and the second technique for constructing the wireless LAN system1100as described above have the following problems.

That is, in the first technique, since the protocol stacks for realizing the wireless LAN system1100must be built in the equipments1101,1104constituting the wireless LAN system1100, the burdens on the equipments in terms of hardware and software are increased, complicating the equipments1101,1104.

Specifically, to provide the built-in wireless LAN function, it is necessary to mount the wireless LAN module1110on the equipments1101,1104, and also to mount various protocols for connection to the Internet1300on the equipment1104as shown inFIG. 33. Thus, in the first technique, the cost for manufacturing the equipments1101,1104is increased and their designs are often redundant for users who do not make connection to the Internet1300.

In the second technique, though connector joint with the equipments1101,1105,1104constituting the wireless LAN system1100can be realized by mounting the wireless LAN function on the PCMCIA card1105, it is necessary to mount various protocols for connection to the Internet1300on the equipment1104as shown inFIG. 34and there is also a problem of cost similar to that of the first technique. Moreover, since the PCMCIA card1105employs a parallel interface in the form of bus, the casing of the equipment1104on which the PCMCIA card is mounted is increased in size, making it difficult to apply the card to a small-size portable equipment.

Furthermore, the equipments1101to1104constituting the wireless LAN system1100need to store the network setting information and the individual information such as the address of the Internet service provider1301, mail address, password and the like in connecting the Internet1300, into the network setting storage section1533and the individual information storage section1534, as shown inFIGS. 31 and 32.

Therefore, the user must set the network setting information and the individual information for each of the equipments1101to1104, and with a portable equipment having a poor man-machine interface function, the operation for setting the network setting information and the individual information is troublesome and generates a large burden.

Particularly, when carrying out processing for changing the Internet service provider1301or the like, it is necessary to change the setting related to network connection of each of the plurality of equipments1101to1104constituting the wireless LAN system1100.

DISCLOSURE OF THE INVENTION

In view of the foregoing status of the art, it is an object of the present invention to provide a communication device, a communication method and a communication terminal device which enable simplification of network setting or the like for connection to the Internet or the like with respect to each portable equipment constituting the wireless LAN system.

In order to solve the foregoing problems, a communication device according to the present invention comprises: wired communication means for providing/receiving data via physical connection means to/from a mounted host equipment; short distance radio communication means for transmitting/receiving data to/from an external communication network via a short distance radio communication network; storage means in which communication setting information as information related to the communication network is stored; and communication control means for setting a connection relation with the communication network via the short distance radio communication network on the basis of the communication setting information stored in the storage means, and controlling transmission/reception of data between the communication network and the host equipment.

A communication method according to the present invention comprises the steps of: using communication setting information as information related to a communication network outside a short distance radio communication network, stored in a communication device, so as to set a connection relation between a radio control device and the communication network via the short distance radio communication network; and carrying out transmission/reception of data between the communication device and the communication network via physical connection means by using the connection relation between the communication device and the communication network, and carrying out transmission/reception between data between a host equipment and the communication device, thus controlling transmission/reception of data between the host equipment and the communication network.

Another communication device according to the present invention comprises: wired communication means for providing/receiving data via physical connection means to/from a mounted host equipment; short distance radio communication means for transmitting/receiving data to/from an external communication network via a short distance radio communication network; storage means in which communication setting information as information related to the communication network is stored; and communication control means for setting a connection relation with the communication network via the short distance radio communication network on the basis of the communication setting information stored in the storage means, and controlling transmission/reception of data between the communication network and the host equipment; the wired communication means, the short distance radio communication means, the storage means, and the communication control means being housed in a single casing; wherein the wired communication means is arranged on one side of the communication control means, and the short distance radio communication means is arranged on the other side of the communication control means.

Another communication device according the present invention comprises, in a casing constituted to have a predetermined outer dimension that allows free attachment/detachment of at least a part thereof to/from a recessed connection part provided in a host equipment: wired communication means for providing/receiving data via physical connection means to/from the mounted host equipment; short distance radio communication means for transmitting/receiving data to/from an external communication network via a short distance radio communication network; storage means in which communication setting information as information related to the communication network is stored; and communication control means for setting a connection relation with the communication network via the short distance radio communication network on the basis of the communication setting information stored in the storage means, and controlling transmission/reception of data between the communication network and the host equipment.

A communication terminal device according to the present invention comprises: public communication connection means operated by a user so as to be connected to a public communication network for providing/receiving data; short distance radio communication means for transmitting/receiving data to/from another equipment included in a short distance radio communication network via the short distance radio communication network; communication setting information storage means in which communication setting information as information related to an external communication network to be connected via the public communication network is stored; communication connection setting means for setting connection with the communication network via the public communication network by using the communication setting information stored in the communication setting information storage means; and control means for controlling to carry out transmission/reception of data between said another equipment and the communication network by using a connection relation with the communication network set by the communication connection setting means.

Other object and specific advantages of the present invention will be clarified further in the following description of embodiments.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is applied to a wireless LAN (local area network) system constituted, for example, as shown inFIGS. 1 and 2.

As shown inFIG. 1, in a wireless LAN system1connected to a public communication network40, the Bluetooth system is employed to realize data communication among a communication equipment2(2ato2e) as gateway, a radio communication device3, and a host equipment4on which the radio communication device3is mounted.

The Bluetooth system is the name of a short distance radio communication technique for which five Japanese and European corporations started standardization activity in May 1998. In accordance with the Bluetooth system, a short distance radio communication network having a maximum data transmission rate of 1 Mbps (in effect, 721 Kbps) and a maximum transmission distance of approximately 10 m is constructed to carry out data communication. In the Bluetooth system, radio waves are transmitted and received between the host equipments4(4ato4d) by employing a spread spectrum technique of the frequency hopping system, in which 79 channels each having a bandwidth of 1 MHZ are set in the ISM (Industrial Scientific Medical) frequency band of a 2.4-GHz band that can be used without permission and the channel is switched 1600 times per second.

A slave-master system is applied to the respective host equipments4included in the short distance radio communication network employing the Bluetooth system, so that these equipments are classified into a master equipment that determines the frequency hopping pattern and slave equipments as counterparts controlled by the master equipment, depending on the processing contents. The master equipment can be connected with seven slave equipments at a time and can carry out data communication simultaneously. A subnet constituted by the total of eight equipments consisting of the master equipment and the slave equipments is referred to as “piconet”. The host equipment4in the piconet, that is, as the slave equipment included in the wireless LAN system1, can be the slave equipment in two or more piconets at the same time.

The wireless LAN system1shown inFIG. 1is constituted by the communication equipment2(2ato2e) for carrying out transmission/reception of data to/from the public communication network40such as the Internet, the radio communication device3for carrying out transmission/reception of a control packet including user data and the like to/from the communication equipment2via a short distance radio communication network30in accordance with the Bluetooth system, and the host equipment4(4ato4d) for carrying out input/output of the control packet including user data and the like to/from the radio communication device3.

The host equipment4is an electronic device which is mechanically connected with the radio communication device3and which is operated by the user. The host equipment4includes, for example, a PDA (personal digital assistant)4a, a digital camera4b, a mail processing terminal4c, an EMD (electronic music distribution) terminal4dand the like.

The communication equipment2is connected to the radio communication device3via the short distance radio communication network30and also connected to the public communication network40. The communication equipment2is the gateway for connecting the radio communication device3with the public communication network40.

The communication equipment2includes a personal computer2ahaving a modem or the like for connecting to the public communication network40, a portable telephone2bemploying, for example, the cdma One (code division multiple access) system or the W-CDMA (wide band-code division multiple access) system, a TA/modem2c, an STB (set top box)2d, and a quasi-public system2esuch as a base station for connecting the radio communication device3conformable to the Bluetooth system with the public communication network40.

The public communication network40includes, for example, the Internet connected to the personal computer2avia a telephone line, a mobile communication network (or mobile network) connected to the portable telephone2b, ISDN (integrated services digital network)/B (broadband)-ISDN connected to the TA/modem2c, a satellite communication network (or broadcasting) connected to the STB2d, WLL (wireless local loop) connected to the quasi-public system2d, and the like.

The Internet included in the public communication network40includes an information providing server41, a mail server42, an EMD server43, and a community server44. The information providing server41receives a request from the host equipment4via the radio communication device3and the communication equipment2, and transmits information corresponding to the request to the host equipment4. The mail server42manages electronic mails and transmits/receives electronic mails to/from the host equipment4via the communication equipment2and the radio communication device3. Moreover, the EMD server43transmits music information to the EMD terminal4dof the host equipment4via the communication equipment2and the radio communication device3, and thus manages music providing services. Furthermore, the community server44provides downloading services for town information and news information to the digital camera4bof the host equipment4, and manages uploading of information from the host equipment4.

In the following description, the wireless LAN system1is described which is constituted by the portable telephone (communication equipment)2for carrying out transmission/reception of data to/from a mobile communication network20, the radio communication device3for carrying out transmission/reception of a control packet including user data or the like to/from the portable telephone2via the short distance radio communication network30in accordance with the Bluetooth system, and the host equipment4for carrying out input/output of a control packet including user data with the radio communication device3, as shown inFIG. 2, to simplify the description.

The portable telephone2has a function to connect to the public communication network40via the mobile communication network20on the basis of a control packet from the radio communication device3. A command to connect the portable telephone2with the public communication network40via the short distance radio communication network30of the Bluetooth system is issued from the radio communication device3.

The host equipment4is, for example, a personal computer, a digital camera, a portable information terminal or the like, and is operated by the user. The host equipment4has a serial interface to connect with the radio communication device3and this interface enables mechanical attachment/detachment of the host equipment4to/from the radio communication device3via a connector.

The radio communication device3has an external structure, for example, as shown inFIG. 3. The radio communication device3has a USB connector51conformable to the USB (universal serial bus) standard. The radio communication device3is mechanically connected with the host equipment4by inserting the USB connector51into a recessed connection part provided in the host equipment4conformable to the USB standard. As the radio communication device3is connected with the host equipment4, the radio communication device3carries out input/output of a control packet with the host equipment4.

Alternatively, the radio communication device3may be constituted as shown inFIG. 4. The radio communication device3in this case has a semiconductor chip for realizing the above-described function of the Bluetooth system, an antenna, a flash memory for storing user data and the like, which are housed in a casing60. The casing60of the radio communication device3is formed in a plate-like shape and its other end60bhas a thickness greater than that of its one end60a.

Furthermore, the radio communication device3may also be constituted as shown inFIG. 5. The radio communication device3in this case has a semiconductor chip for realizing the function of the above-described function of the Bluetooth chip, an antenna, a flash memory and the like housed in a casing60, similarly to the radio communication device3shown inFIG. 4. The casing60of the radio communication device3is formed in a plate-like shape, and its one end60aand its other end60bhave the same thickness.

In the radio communication device3shown inFIGS. 4 and 5, a plurality of connection terminals61are provided on the one end60aof the casing60, as shown inFIG. 6. By having the plurality of connection terminals61, the radio communication device3is electrically connected with the host equipment4. The radio communication device3has a 10-pin structure including at least a terminal for detecting the attachment to/detachment from the host equipment4, a terminal for inputting/outputting a control packet with the host equipment4, and the like.

The radio communication device3having the external structure as shown inFIGS. 3 to 6has an internal structure as shown inFIGS. 7A and 7B. The radio communication device3has various chips including an antenna section3a, an RF module3b, a base band processing section (large scale integrated circuit)3c, and a flash memory3d, which are housed in the single casing60, as shown inFIG. 7A. In the RF module3b, a switch section (SW), a receiving section, a transmitting section, and a hopping synthesizer section are housed. In the base band processing section3c, a base band control section, an interface section, an individual information storage section, a network setting storage section, a RAM (random access memory), a radio communication CPU (central processing unit), a ROM (read only memory), and a memory controller are housed. The various sections housed in the RF module3band the base band processing section3cwill be described later.

The sections3ato3dare arranged and housed in the casing60in the order of the antenna section3a, the RF module3b, the base band processing section3c, and the flash memory3dfrom the other end60btoward the one end60a, as shown inFIG. 7B.

The sections3ato3dhoused in the radio communication device3are not limited to the structure shown inFIGS. 7A and 7B, and may also be constituted as shown inFIG. 8. The structure shown inFIG. 8differs in that an EEPROM (electrically erasable and programmable read only memory)3eis provided in addition to the antenna section3a, the RF module3band the base band processing section3c. Moreover, in the base band processing section3cshown inFIG. 8, a DMAC (direct memory access controller), a flash memory of 256 KB, a CPU, a RAM of 72 KB, a base band control section, an interface circuit (IIC) with respect to the EEPROM3e, and an MS I/F (memory stick (trademark) interface) conformable to the existing memory card standard are connected to a data bus, and a memory controller is further provided.

More specifically, the radio communication device3is constituted as shown inFIGS. 9A and 9B. The radio communication device3has a board62inside the casing60, and the antenna section3a, the RF module3b, the base band processing section3cand the flash memory3dare mounted on the board62. Moreover, the radio communication device3has a 10-pin terminal section60eon the other end60b. As these sections3ato3dare formed on the board62, electrical connection via the board62is realized.

The casing60of the radio communication device3has, for example, a longitudinal dimension t1of 21.45 mm, a lateral dimension t2of 50.0 mm, and a height t3of 2.8 μm. The antenna section3ais made of a chip antenna integrated on the board and has, for example, a longitudinal dimension of 9.5 mm, a lateral dimension of 2.0 mm, and a height of 1.5 μm. The base band processing section3chas a longitudinal dimension of 9 mm and a lateral dimension of 9 mm.

A mounting method for mounting such antenna section3a, RF module3b, base band processing section3c, flash memory3dand terminal section60einside the casing60will be described with reference toFIG. 10. InFIG. 10, from the other end60bof the radio communication device3, the antenna section3a, the RF module3b, the base band processing section3c, and the flash memory3dare mounted and arranged on the board62. The mounting method for the antenna section3a, a function element, the RF module3band the base band processing section3cwill now be described.

The antenna section3ais a mounted chip antenna mounted in the board62. The antenna section3amay also be another antenna such as a bow-tie antenna, an inverted F antenna, a patch antenna, or a dipole antenna. As shown inFIG. 11, the antenna section3ais formed integrally with the board62arranged in the casing60and is mounted in the state of being embedded in the board62. In the radio communication device3, the shape of the other end60bof the casing60is deformed as shown inFIG. 4orFIG. 5, depending on the type of the antenna section3ato be used.

The RF module3band the base band processing section3care mounted on a multilayer board63formed on the board62, as shown inFIGS. 11 and 12. In this case, the multilayer board63has a four-layer structure, in which a through-hole64having a metal film formed on its inner wall is formed so as to realize conduction among the respective layers. Thus, in the radio communication device3, electrical conduction among the antenna section3a, the RF module3b, the base band processing section3c, the flash memory3dand the terminal section60eis secured and input/output of a packet is carried out among the respective sections.

The RF module3bis mounted on a metal pattern formed on the multilayer board63via a flip-chip connecting section65by using a flip-chip technique on the multilayer board63.

On the multilayer board63where the RF module3bis mounted, a capacitor66and a resonator (filter)67are mounted as they are built between the layers, and an inductor68is mounted on the back side of the multilayer board63. Moreover, a chip component69is mounted on the multilayer board63.

When mounting the base band processing section3con the multilayer board63, a wiring board72, the base band processing section3c, a flip-chip connecting section73, and a flash ROM are sequentially stacked on solder balls71, as shown inFIG. 12, and in the state where these are integrated, the base band processing section3cis mounted on the multilayer board63by using the flip-chip technique. In this case, the base band processing section3csecures electrical conduction of the adjacent RF module3band flash memory3dby connecting a wire75by a wire bonding technique. Moreover, when mounting the base band processing section3c, a radio absorptive material76is formed in order to prevent radio interference with the other sections.

Furthermore, when mounting the flash memory3don the board62, a multilayer board is used which has such a structure that ultra thin boards77and solder balls78provided between the ultra thin boards77are alternately stacked, as shown inFIG. 13. The respective ultra thin boards77are supported by the solder balls78and thus stacked at a predetermined spacing. When mounting the flash memory3d, the flash memory3dis mounted between the ultra thin boards77via a flip-chip connecting section79by using a flexible mounting technique and the flip-chip technique. In this case, four thin chips are used as the flash memory3d.

The RF module3band the base band processing section3cthus mounted are covered by a radio wave absorbent mold3f, as shown inFIG. 14, in order to prevent radio waves from outside.

In the radio communication device3, the antenna section3a, the RF module3b, the base band processing section3c, and the flash memory3dare mounted on the board62, as described above. Thus, the antenna section3a, the RF module3b, the base band processing section3c, and the flash memory3dcan be sequentially mounted from the other end60btoward the one end60a. By using the above-described technique, the antenna section3a, the RF module3b, the base band processing section3c, and the flash memory3dcan be housed within the casing60having a thickness of 2.8 μm, a longitudinal dimension of 50.0 mm and a lateral dimension of 2.4 mm.

The radio communication device3of such a structure is loaded in the host equipment4such as a personal computer, in a mode as shown inFIG. 15. Specifically, when the output terminals61provided on the one end60aof the casing60of the radio communication device3are connected to a recessed connecting section4fof the personal computer, the one end60ais held inside the recessed connecting section4fof the personal computer and the other end60bis exposed outside of the personal computer. By thus connecting the radio communication device3with the personal computer so as to expose the other end60bto the outside, at least a part of the casing60covering the antenna section3ais exposed to the outside.

In the case where the radio communication device3has the casing60of the external structure as shown inFIG. 4, the radio communication device3is connected with the personal computer so that the other end60bhaving a greater thickness than the one end60ais exposed outside the personal computer.

The protocol stacks mounted on the portable telephone2, the radio communication device3and the host equipment4, which constitute the wireless LAN system1, will now be described with reference toFIG. 2.

The portable telephone2has mounted thereon a protocol stack11which has a physical layer (PHY), a medium access control layer (MAC) and a logical link control layer (LLC) for realizing the wireless LAN system1of the Bluetooth system, as lower three layers. By using the protocols of the lower three layers, the portable telephone2carries out transmission/reception of a control packet to/from the radio communication device3via the short distance radio communication network30.

The portable telephone2also has mounted thereon a W-CDMA (wide band-code division multiple access) protocol as the upper layer with respect to the lower three layers. As the portable telephone2has the W-CDMA protocol mounted thereon and is set in the data communication mode by the radio communication device3, connection to the public communication network40is realized via the mobile communication network20. The portable telephone2may also have mounted thereon a protocol that is different from the W-CDMA protocol.

The radio communication device3has a radio transmission/reception function and a protocol control function. The radio communication device3carries out transmission/reception of a control packet via the portable telephone2and the short distance radio communication network30, and carries out input/output of data from/to the host equipment4.

Similar to the portable telephone2, the radio communication device3has mounted thereon a protocol stack12which has a physical layer (PHY), a medium access control layer (MAC) and a logical link control layer (LLC) of the Bluetooth system, as lower three layers. By using the protocols of the lower three layers, the radio communication device3carries out transmission/reception of data to/from the portable telephone2via the short distance radio communication network30. The structure and processing contents of the radio communication device3will be later described further in detail.

The radio communication device3also has mounted thereon a PPP (point to point protocol) layer, an IP (Internet protocol) layer and a TCP (transmission control protocol) layer as the upper layers above the lower three layers for constituting the short distance radio communication network30. The radio communication device3executes processing conformable to the PPP so as to carry out dial-up access to the Internet service provider included in the public communication network40, and executes processing conformable to the IP and TCP so as to control the portable telephone2to connect to the WWW (world wide web) server included in the public communication network40.

Moreover, the radio communication device3also has mounted thereon a HOST I/F layer for physical connection with the host equipment4, as the upper layer above the TCP layer. The HOST I/F layer is a layer for connecting with the host equipment and then carrying out input/output of user data. The HOST I/F layer is a layer for carrying out processing that is to be carried out, for example, by a USB or an existing interface for inputting/outputting only the data stored in the flash memory.

The host equipment4has mounted thereon a HOST I/F layer corresponding to the HOST I/F layer mounted on the uppermost layer of the radio communication device3, and an application (AP) layer as the upper layer with respect to the HOST I/F layer. By having the HOST I/F layer mounted thereon, the host equipment4inputs/outputs user data generated by the application (AP) from/to the radio communication device3. The application layer stored in the host equipment4is equivalent to installed application software, if the host equipment4is a personal computer.

Also, the host equipment4is operated by the user and thus generates an operation input signal. The host equipment4generates, for example, an operation input signal to the effect that it is to be connected with the portable telephone2via the radio communication device3and the short distance radio communication network30, and outputs a control command accordance to the operation input signal, to the radio communication device3. Thus, as the portable telephone2is connected with the public communication network40, the host equipment4is connected with the public communication network40via a public network made up of the short distance radio communication network30and the mobile communication network20.

Moreover, when the radio communication device3is loaded in the host equipment4, the host equipment4carries out input/output of a control packet including user data from/to the radio communication device3via the HOST I/F layer by using a serial interface.

FIG. 16shows a block diagram of the radio communication device3and the host equipment4constituting the wireless LAN system1.

The radio communication device3has a communication control section81for carrying out radio communication in the wireless LAN system1, an antenna section82for transmitting/receiving user data and the like to/from each section constituting the wireless LAN system1, a base band control section83for controlling communication carried out by the communication control section81, and an interface section84for carrying out input/output of a control packet including user data from/to the host equipment4. In this case, the communication control section81corresponds to the above-described RF module3b, and the base band control section83corresponds to the above-described base band processing section3c.

The antenna section82is made up of an antenna for transmitting/receiving signals in a 2.4-GHz band (2.402 to 2.480 GHz). The antenna section82transmits data from the communication control section81to the portable telephone2via the short distance radio communication network30, and also receives a signal from the portable telephone2via the short distance radio communication network30and outputs it to the communication control section81. The antenna section82corresponds to the above-described antenna section3a.

With respect to the data in the short distance radio communication network30transmitted/received by the antenna section82, a control packet which consists of a predetermined number of bits and is made up of user data and control data is transmitted/received as a minimum unit.

The communication control section81has a receiving section91for carrying out processing to receive a control packet from the antenna section92, a transmitting section92for carrying out processing to transmit a control packet from the antenna section82, a switch section93for switching transmission of a control packet from the transmitting section92via the antenna section82and output of a control packet from the antenna section82to the receiving section91, and a hopping synthesizer section94for carrying out spectrum spreading by frequency hopping with respect to control packets in the receiving section91and the transmitting section92.

The switch section93operates in response to a control signal from a radio communication CPU (central processing unit)89, which will be described later. When receiving a control packet from the antenna section82, the switch section93operates so as to output the control packet from the antenna section82to the receiving section91. When transmitting a control packet from the antenna section82, the switch section93operates so as to output the control packet from the transmitting section92to the antenna section82.

The receiving section91receives the control packet from a switch section93and outputs it to the base band control section83. The receiving section91has a hopping frequency pattern designated therefor by the hopping synthesizer section94. Thus, the receiving section91receives the control packet in accordance with the frequency pattern of the case of receiving the control packet from the switch section93and then outputs the control packet to the base band control section83. In this case, the receiving section91carries out processing to multiply the frequency pattern designated for each packet by the hopping synthesizer section94, and outputs the resultant control packet to the base band control section83.

The transmitting section92is supplied with a control packet of each packet unit which is generated and primary-modulated by the base band control section83, and outputs the control packet to the switch section93, as the control packet to be outputted to the portable telephone2via the short distance radio communication network30from the antenna section82. The transmitting section92has a frequency pattern designated therefor by the hopping synthesizer section94and outputs the control packet to the switch section93in accordance with the designated frequency pattern. In this case, the transmitting section92carries out processing to perform frequency conversion on each packet unit by using the frequency pattern designated by the hopping synthesizer section94and then to transmit the control packet.

The hopping synthesizer section94has a hopping pattern designated for frequency hopping from the base band control section83. When receiving a control packet from the antenna section82, the hopping synthesizer section94outputs the frequency pattern of the hopping pattern designated by the base band control section83to the receiving section91. When transmitting a control packet from the antenna section82, the hopping synthesizer section94outputs to the transmitting section92the frequency pattern for the transmitting section92to perform frequency conversion on the data from the base band control section83. The hopping synthesizer section94is controlled by the base band control section83so as to designate the same frequency pattern as those of the receiving section91and the transmitting section92.

The hopping synthesizer section94carries out frequency conversion so as to perform frequency hopping 1600 times per second, for example, on 79 channels obtained by splitting the band every 1 MHZ (2.402 to 2.480 GHz).

The base band control section83carries out the following processing in accordance with a control signal from the radio communication CPU89, which will be described later.

The base band control section83is supplied with a control packet of each packet unit from the receiving section91, and carries out processing to demodulate the control packet which is frequency-modulated by frequency hopping. When transmitting a control packet from the antenna section82, the base band control section83performs primary modulation on the control packet to be transmitted and then outputs the resultant control packet to the transmitting section92.

Moreover, the base band control section83provides a hopping pattern to the hopping synthesizer section94, thereby controlling the hopping synthesizer section94. Thus, the base band control section83controls the transmission timing for the control packet to be transmitted from the radio communication device3and also controls the reception timing for the control packet to be received. The base band control section83provides, for example, a frequency pattern f(k), f(k+1), f(k+2), . . . as the hopping pattern to the hopping synthesizer section94at every predetermined time.

Furthermore, the base band control section83converts a control packet into a predetermined packet format and outputs each control packet as a unit to the receiving section91. The base band control section83also carries out processing to decompose a control packet of the predetermined packet format from the transmitting section92and outputs the decomposed control packet to the radio communication CPU89via the interface section84or the data bus.

The predetermined packet format consists of SYNC (synchronous) data, PID (packet ID) data, PAYLOAD, and CRC (cyclic redundancy code) data, for example, as shown inFIG. 17, and is basically conformable to the bulk transfer system of the USB standard.

The SYNC data is a synchronization code word indicating the start of the packet.

The PID data is an identifier for identifying the packet and therefore data indicating the type of the packet.

The PAYLOAD is an area in which control data and user data are stored.

The CRC data is a CRC parity for detection of an error, provided with respect to the PAYLOAD.

The interface section84operates in accordance with a control signal from the radio communication CPU89. The interface section84is supplied with the control packet received from the antenna section82via the communication control section81and the base band control section83, then performs predetermined conversion processing on the control packet, and outputs the resultant control packet to the host equipment4. When transmitting a control packet from the antenna section82, the interface section84outputs the control packet inputted via the host equipment4to the base band control section83.

The interface section84may be, for example, a serial interface having the specification similar to that of a memory stick (trademark registered), as shown inFIGS. 5 and 6.

The radio communication device3also has an individual information storage section85for storing individual information provided for each user, and a network setting storage section86for storing network setting information indicating necessary information for connecting the host equipment4with networks such as the short distance radio communication network30and the public communication network40.

In the individual information storage section85, the mail address of the user owning the host equipment4, the user ID for connecting to an access point, the password (for PPP connection) and the like are stored as individual information. The information in the individual information storage section85is read and has its contents controlled by the radio communication CPU89.

In the case where an electronic mail application is assumed as an application to be executed by the radio communication device3, the following information may be stored in the individual information storage section85: information indicating an electronic mail address list (address book) of destinations of electronic mails, information indicating the transmission/reception record, information indicating a fixed text list for realizing simplification of input to the host equipment4(for example, a digital camera) which has a poor character input function, signature information to be added at the end of texts of a transmitted electronic mail, information indicating the mail unique ID for carrying out management of mails that are not read and mails that have been read in receiving electronic mails, and the like.

Moreover, SIM (subscriber identification module) information may also be stored in the individual information storage section85. The SIM information stored in the individual information storage section85is information which is required for identifying the user and which is encrypted inside the radio communication device3so as to improve the security. The SIM information includes, for example, the user ID, the user password, the mail ID for accessing the mail box of an individual, the mail password, the mail address of the user, the password for individual identification for confirming the right of use of the radio communication device3itself and the like, which are encrypted.

In the network setting storage section86, the server address, the telephone number of an access point or the like, which are required when the host equipment4makes dial-up access to the Internet service provider of the public communication network40, are stored as the network setting information. The network setting information is read and has its contents controlled by the radio communication CPU89.

The radio communication device3also has a RAM (random access memory)87, ROM (read only memory)88, and the radio communication CPU89which are connected to a data bus.

The radio communication CPU89reads a control program for controlling each section constituting the radio communication device3from the ROM88via the data bus and thus generates a control signal. The radio communication CPU89stores data into the RAM87as a work space, when necessary, and executes the control program to generate the control signal. Thus, the radio communication CPU89controls the base band control section83, the communication control section81and the interface section84so as to generate a control packet for controlling communication with another equipment constituting the wireless LAN system1and to carry out transmission/reception of the control packet to/from the host equipment4via the interface section84. The contents of processing carried out by execution of the control program by the radio communication CPU89will be later described in detail.

The host equipment4has an interface section101for carrying out input/output of data from/to the interface section84of the radio communication device3, and a host CPU102for controlling the interface section101or the like via a data bus.

The interface section101is made up of a serial interface such as USB capable of carrying out input/output of a control packet including user data with the interface section84of the radio communication device3.

The interface section101may also be a serial interface capable of carrying out transmission/reception of a control packet to/from the interface section84of the radio communication device3, as shown inFIGS. 5 and 6.

The host CPU102generates a control packet including user data generated by the host equipment4and control data such as an operation input signal or the like generated by operation by the user. The host CPU102executes the processing in the application layer, thereby generating the user data and the control data. The host CPU102executes the processing in the HOST I/F layer, thereby generating a control packet, and outputs the control packet to the radio communication device3via the interface section101.

The radio communication device3and the host equipment4are in a master-slave relation. The host equipment4is a master and the radio communication device is a slave. That is, the radio communication device3operates in accordance with a control packet or the like from the host CPU102. For example, in the case of outputting the user data from the radio communication device3to the host equipment4, the radio communication device3can output the user data to the host equipment4only when a control packet to the effect that the right to use the serial data line for connecting to the host equipment4is inputted to the radio communication CPU89from the host CPU102.

More specifically, when transmitting/receiving the user data between the radio communication device3and the host equipment4, a control packet of the packet format shown inFIG. 17is outputted from the host equipment4to the radio communication CPU89of the radio communication device3at a predetermined time interval.

That is, when transmitting the user data to the radio communication device3, the host CPU102of the host equipment4generates a control packet in which control data indicating “OUT token packet” as the PID data is stored, and outputs the control packet to the radio communication CPU89. When the host CPU102can accept the user data from the radio communication device3, the host CPU102generates a control packet in which control data indicating “IN token packet” as the PID data is stored, and outputs the control packet to the radio communication CPU89. Thus, control packets including user data can be bidirectionally inputted/outputted between the radio communication device3and the host equipment4.

Moreover, the host CPU102generates and outputs a control packet in which the contents of the PID data are changed in accordance with the control contents of the radio communication device3, thereby controlling the operation mode of the radio communication device3. Specifically, the host CPU102outputs the control packet to the radio communication CPU89, thus switching the mode of the radio communication device3to a communication idle mode, a memory mode, an OUT transaction mode, or an IN transaction mode.

FIG. 18shows a state transition view of the radio communication device3with its operation mode switched by the host CPU102.

In this case, the radio communication device3is normally set in the communication idle mode (step ST1), that is, an operation mode in which a control packet is not transmitted from the host equipment4to the radio communication device3and in which the radio communication device3is on standby for communication processing.

When a control packet in which control data indicating “OUT token packet” as PID data is stored is inputted to the radio communication CPU89from the host CPU102, the radio communication CPU89shifts to the OUT transaction mode (step ST2), that is, an operation mode in which user data is transmitted from the host equipment4.

In the OUT transaction mode, when it is determined from the CRC data of the control packet that no error is included in the PAYLOAD, the radio communication CPU89generates a control packet in which control data indicating a “ACK (acknowledgment)” as PID data is stored, and transmits the control packet to the host equipment4(step ST2a). Then, the radio communication CPU89returns to the communication idle mode (step ST1).

In the OUT transaction mode, when it is determined from the CRC data of the control packet that an error is included in the PAYLOAD, the radio communication CPU89generates a control packet in which control data indicating “NAK (negative acknowledgment)” as PID data is stored, and transmits the control packet to the host equipment4(step ST2b). Then, the radio communication CPU89returns to the communication idle mode (step ST1).

Moreover, in the OUT transaction mode, when the radio communication CPU89cannot receive the control packet, the radio communication CPU89generates a control packet in which control data indicating “STALL” as PID data is stored, and transmits the control packet to the host equipment4(step ST2c). Then, the radio communication CPU89returns to the communication idle mode (step ST1).

When a control packet in which control data indicating “IN token packet” as PID data is housed is inputted to the radio communication CPU89from the host CPU102, the radio communication CPU89shifts from the communication idle mode (step ST1) to the IN transaction mode (step ST3), that is, an operation mode in which transmission of user data from the host equipment4to the radio communication device3is permitted.

In the IN transaction mode (step ST3), the radio communication CPU89generates a control packet including user data and carries out transmission of the user data (step ST3a). In this case, the radio communication CPU89stores, into each control packet, control data having PID data sequentially changed to “DATA0” and “DATA1” as toggle, and transmits the control packet to the host CPU102. Thus, the radio communication CPU89and the host CPU102mutually confirm transmission of the control packet to be inputted/outputted.

In response to the transmission (step ST3a) of the control packet to the host equipment4, the radio communication CPU89is set in the standby state until a control packet indicating a response from the host CPU102is transmitted. The response to be transmitted from the host CPU102to the radio communication CPU89is ACK reception (step ST3b) indicating that the data is securely transmitted from the radio communication device3to the host equipment4, NAK reception (step ST3c) indicating that the data is not transmitted from the radio communication device3to the host equipment4, or STALL reception (step ST3d) indicating that the host equipment4is not in the state for receiving the data.

The radio communication CPU89shifts to the communication idle mode (step ST1) in response to the reception of a control packet having control data indicating ACK reception, NAK reception or STALL reception stored in the PAYLOAD.

When a control packet in which control data indicating “network/individual information setting mode” as PID data is stored is inputted to the radio communication CPU89from the host CPU102, the radio communication CPU89shifts from the communication idle mode (step ST1) to a network/individual information setting mode (step ST4).

In the network/individual information setting mode, the radio communication CPU89carries out processing such as reading, writing, updating, erasing or the like of the individual information stored in the individual information storage section85and the network setting information stored in the network setting storage section86, and then returns to the communication idle mode (step ST1). In this case, the radio communication CPU89carries out processing such as reading, writing, updating, erasing or the like of the individual information and the network setting information, for example, in accordance with the control data stored in the PAYLOAD.

When connecting the radio communication device3to the public communication network40via the short distance radio communication network30, the host CPU102transmits a control packet to that effect to the radio communication CPU89, thus controlling the connection with the Internet service provide in the public communication network40. The processing procedure for connecting host equipment4with the public communication network40via the radio communication device3, the short distance radio communication network30and the mobile communication network20will be described later.

Hereinafter, the processing to be carried out by the radio communication CPU89for connecting the host equipment4with the WWW server in the public communication network40in the above-described wireless LAN system1will be described with reference to the flowchart ofFIG. 19.FIG. 19shows the data transmitted/received among the host equipment4, the radio communication device3, the portable telephone2, the public network comprising the mobile communication network20and the public communication network40, the Internet service provider included in the public communication network40, and the WWW server included in the public communication network40, and mainly shows the processing contents of the radio communication CPU89.

InFIG. 19, first, the host CPU102transmits a control packet indicating an originating request S1for originating user data from the host equipment4to the WWW server included in the public communication network40, to the radio communication CPU89.

Then, in response to the originating request S1, the radio communication CPU89starts the PPP stored in the ROM88, at step ST11.

The radio communication CPU89carries out processing to generate a control packet having the originating request and telephone number S2stored in PAYLOAD, with reference to the telephone number of the Internet service provider of the access destination stored in the network setting storage section86, and transmits the originating request and telephone number S2to the portable telephone2via the short distance radio communication network30.

Then, in response to the originating request and telephone number S2from the radio communication device3, the portable telephone2transmits first call setting S3(Set up (1)) to the public network. In response to this, the public network transmits second call setting S4(Set up (2)) having the contents similar those of the first call setting S3to the Internet service provider via a plurality of repeaters such as routers. As the Internet service provider responds, the public network is supplied with and receives first connection information S5(Connect (2)) for confirming connection, from the Internet service provider. Then, in response to the reception of the first connection information S5, the public network transmits second connection information S6(Connect (1)) having the contents similar to those of the first connection information S5to the portable telephone2.

The portable telephone2transmits connection completion information S7indicating that the connection with the Internet service provider is completed, to the radio communication device3via the short distance radio communication network30.

At the next step ST12, the radio communication CPU89shifts to a link establishment phase as the PPP in response to the connection completion information S7received from the portable telephone2.

At the next step ST13, the radio communication CPU89carries out authentication processing with the PPP. In this case, the radio communication CPU89reads out the user ID and password from the individual information storage section85and transmits/receives authentication information S8for mutually authentication with the Internet service provider via the portable telephone2and the public network by using the PPP, thus carrying out the authentication processing.

At the next step ST14, the radio communication CPU89completes the authentication processing by transmitting/receiving the authentication information S8to/from the Internet service provider, and then enters an authentication establishment phase. The radio communication CPU89outputs a control packet including connection completion information S9indicating that the connection between the radio communication device3and the Internet service provider is completed, to the host CPU102of the host equipment4.

At the next step ST15, the radio communication CPU89shifts to a network layer protocol phase in response to the completion of the authentication processing of step ST14. Specifically, the radio communication CPU89executes processing in conformity with the IP and TCP mounted in the protocol stack, thereby making connection with the public communication network40.

At the next step ST16, the host CPU102stores user data into PAYLOAD of the control packet and carries out input/output of user data S10with the radio communication device3. Also, the host CPU102packetizes the user data S10by adding control information to the user data S10in accordance with the TCP and IP, and carries out transmission/reception of packetized user data S11between the radio communication device3and the WWW server in the public communication network40.

With the radio communication device3which carries out the above-described processing, since it has the individual information storage section85and the network setting storage section86in which the individual information and the network setting information are stored, respectively, connection with the Internet service provider can be made by starting the PPP by the radio communication CPU89and then using the individual information and the network setting information. Also, with the radio communication device3, connection between the host equipment4and the WWW server can be made by starting the IP and TCP, then transmitting/receiving the encapsulated user data to/from the WWW server using the individual information and the network setting information, and connecting to the host equipment4using the control packet.

Thus, with the radio communication device3, since it is not necessary to store the individual information and the network setting information in the host equipment4, it is not necessary to carry out various types of setting for each host equipment4for connection with the public communication network40, and the network setting or the like for connecting to the public communication network40can be simplified for each host equipment4. Therefore, in the wireless LAN system1, the connection setting between each host equipment4and the WWW server can be carried out by loading the radio communication device3in each host equipment4.

Also, with the radio communication device3, transmission/reception of data between the host equipment4and the public communication network40can be carried out irrespective of the type of the host equipment4, by transmitting/receiving a control packet of the common packet structure for the respective host equipments4to/from the individual information storage section85and the network setting storage section86.

Moreover, with the radio communication device3, in carrying out transmission/reception of data between the host equipment4and the public communication network40, the individual information and the network setting information can be shared by the respective host equipments4by performing single-element management of the address information of the server or the like included in the public communication network40and the transmission/reception record, irrespective of the type of the host equipment4, and the trouble of setting the individual information and the network setting information for each host equipment4can be eliminated.

As shown inFIG. 20, in the wireless LAN system1where a portable information terminal4a, a personal computer4b, a conversion adapter4c, a gate machine4dand a television4eexist as the host equipment4, for example, as the radio communication device3is loaded in the host equipment4c, the radio communication device3can connect the game machine4d, which is not capable of loading the radio communication device3therein, with the WWW server.

In such a wireless LAN system1, when carrying out setting for connecting an equipment having poor operation and display capability such as a digital camera with the WWW server, it is not necessary to carry out various types of setting in the digital camera. By using the portable information terminal4aor the personal computer4bhaving a more advanced man-machine interface than that of the digital camera, the individual information and the network setting information stored in the radio communication device3can be set. Thus, with the wireless LAN system1having the radio communication device3, connection between the digital camera and the WWW server can be made by loading the radio communication device3which has carried out network setting in the personal computer4b, into the digital camera, and the network setting can be easily carried out for the digital camera or the like having poor operation and display functions.

Moreover, a user who does not have the personal computer4bmay combine the game machine4dwith the television4eand set the individual information and the network setting information via the conversion adapter4c. Since the radio communication device3and the game machine4dcannot carry out input/output of signals directly with each other, input/output of signals between the radio communication device3and the game machine4dis carried out by using a USB or the conversion adapter4cbetween the interface of a radio communication device with a memory function, which will be described later, and the interface of the game machine4d. Thus, the network setting or the like can be easily carried out. By loading the radio communication device3which has carried out the network setting in another host equipment4such as game equipment4dor the television4einto the digital camera, connection between the digital camera and the WWW server is made possible and the digital camera can be used, for example, as a dynamic image viewer.

With the above-described radio communication device3, it is not necessary to provide a function for constructing the wireless LAN system1on the side of the host equipment4and a function for connecting to the public communication network40, as built-in functions, and the cost of the host equipment4can be reduced.

The host CPU102is not limited to the example in which it starts the PPP, IP and TCP mounted in the radio communication device3and controls connection to the Internet. It is also possible to mount the PPP, IP and TCP inside the host equipment4and select connection to the Internet using the protocols mounted in the radio communication device3or connection to the Internet using the protocols mounted in the host equipment4.

Specifically, unlike the example of the wireless LAN system1shown inFIG. 2, the PPP, IP and TCP for carrying out network setting may be provided in the protocol stack14mounted in the host equipment4, as shown inFIG. 21.

In the case of making connection with the public communication network40by using the wireless LAN system1having such a host equipment4, when the PPP, IP and TCP stored in the host equipment4are used, the PPP, IP and TCP mounted in the radio communication device3are not started and a path L1for inputting/outputting a control packet between the HOST I/F layer and the LLC layer in the radio communication device3is used. Thus, in the radio communication device3, a memory space which would be required for starting the PPP, IP and TCP can be used for storing other data. On the other hand, when the PPP, IP and TCP stored in the radio communication device3are used, the PPP, IP and TCP mounted in the host equipment4are not used and a path L2for inputting/outputting a control packet between the AP layer and the HOST I/F layer in the host equipment4is used.

Alternative processing procedure for connecting the host equipment4with the WWW server in the public communication network40in the wireless LAN system1shown inFIG. 21will now be described with reference toFIGS. 22 and 23. In the following description ofFIGS. 22 and 23, the processing similar the processing shown inFIG. 19is denoted by the same numeral and will not be described further in detail.

InFIG. 22, first, an originating request S21for requesting connection between the host equipment4and the WWW server in the public communication network40is outputted from the host CPU102to the radio communication device3.

At the next step ST21, when only the originating request S21is transmitted to the radio communication CPU89of the radio communication device3, the radio communication CPU89determines to use an internal protocol stored, for example, in the ROM88and mounted inside. Then, the radio communication CPU89carries out processing of steps ST11to ST16similarly to the processing described with reference toFIG. 19, thereby connecting to the Internet service provider in the public communication network40and making connection between the host equipment4and the WWW server. That is, the radio communication CPU89carries out processing of each layer of the protocol stack14with respect to a control packet by using the path L1.

On the other hand, as shown inFIG. 23, if processing to start the PPP as an internal protocol stored in the built-in ROM is carried out by the host CPU102at step ST31, and an originating request and telephone number of the Internet service provider S31is inputted, the radio communication CPU89determines not to use the internal protocol at step ST21. That is, the radio communication CPU89carries out processing of each layer of the protocol stack12with respect to a control packet by using the path L2.

The host equipment4causes the portable telephone2to transmit an originating request and telephone number S2having the same contents as those of the originating request and telephone number S31to the radio communication device3via the short distance radio communication network30, as described above with reference toFIG. 19, and then carries out the following processing.

That is, the host equipment4transmits first call setting S3(Set up (1)) to the public network and transmits second call setting S4of the same contents as those of the first call setting S3from the public network to the Internet service provider. In this case, as the Internet service provider responds, the public network is supplied with and receives first connection information S5for confirming the connection from the Internet service provider. In response to the reception of the first connection information S5, second connection information S6of the same contents as those of the first connection information S5is transmitted from the public network to the portable telephone2, and connection completion information S7indicating that the connection with the Internet service provider is completed is transmitted from the portable telephone2to the radio communication device3via the short distance radio communication network30. The radio communication device3outputs connection completion information S32of the same contents as those of the connection completion information S7, as a control packet, to the host equipment4.

At the next step ST32, the host CPU102shifts to a link establishment phase as the PPP in response to the connection completion information S32received from the portable telephone2.

At the next step ST33, the host CPU102carries out authentication processing with the PPP. In this case, the host CPU102is supplied with the user ID and password as a control packet from the individual information storage section85of the radio communication device3via the interface section84and the interface section101, and transmits/receives authentication information S33for mutual authentication with the Internet service provider via the radio communication device3, the portable telephone2and the public network in accordance with the PPP, thus carrying out the authentication processing.

At the next step ST34, the host CPU102completes the authentication processing by transmitting/receiving the authentication information to/from the Internet service provider, and then enters an authentication establishment phase.

At the next step ST35, the host CPU102shifts to a network layer protocol phase in response to the completion of the authentication processing at step ST34. That is, the host CPU102makes connection with the public communication network40by using the IP and TCP mounted in the protocol stack.

At the next step ST36, the host CPU102packetizes the user data by adding control data to the user data in accordance with the TCP and IP and carries out transmission/reception of packetized user data S34to/from the WWW server in the public network communication40via the radio communication device3.

Therefore, with the wireless LAN system1capable of carrying out such processing, even in the case of connecting to the public communication network40using the host equipment4on the basis of the determination to use the internal protocol stored in the host equipment4at step ST21inFIG. 23, the individual information and the network setting information are inputted to the host CPU102from the individual information storage section85and the network setting storage section86of the radio communication device3via the interface section84and the interface section101. Thus, it is not necessary to store the individual information and the network setting information on the side of the host equipment4and to carry out setting for each host equipment4for connection to the public communication network40, and the network setting or the like for connection to the public communication network40can be easily carried out for each host equipment4.

A radio communication device with a memory function200having a flash memory as shown inFIG. 7will now be described. The radio communication device with a memory function200is used for carrying out input/output of serial data with a digital camera4A as the host equipment4, as shown inFIG. 24.

The radio communication device with a memory function200has a flash memory111for storing image data obtained by shooting with the digital camera4A, a memory controller112for managing the contents of the flash memory111, and an interface section113connected with the digital camera4A for carrying out input/output of image data or the like. The interface section113is a serial interface constituted as shown inFIGS. 5 and 6and having the same specification as a memory stick (trademark). That is, the radio communication device with a memory function200has a plurality of terminals at which the bus state indicating the state of a serial bus when it is connected with an external equipment, data, clock and the like are inputted/outputted.

More specifically, the radio communication device with a memory function200may have the same shape and specification as an existing memory card having a built-in flash memory and employing a serial protocol as the interface. That is, the radio communication device with a memory function200has, for example, a casing with a longitudinal dimension of 50.0 mm, a lateral dimension of 2.5 μm and a thickness of 2.8 mm, having the flash memory and the memory controller112housed therein. In the radio communication device with a memory function200, transmission/reception of data to/from the host equipment4is carried out by using only the three pins for the data, clock and bus state, of 10 pins. The clock and bus state are supplied from the host equipment4, and the data is transferred by bidirectional half-duplex transfer. When transmitting/receiving a control packet as data between the radio communication device with a memory function200and the host equipment4, the maximum frequency of the clock is set at 20 MHZ and an error check code with 512 bytes as a basic unit is added, thus carrying out transfer.

The memory controller112carries out processing in accordance with the protocol of the serial interface and controls the contents of the flash memory111. In the case where the flash memory111is made up of a plurality of flash memories, the memory controller112controls the contents of each flash memory. Moreover, in the case where the flash memory111is made up of a plurality of flash memories of different types, the memory controller112absorbs the characteristic difference of the various flash memories so as to control each flash memory, and carries out error correction processing corresponding to the error characteristics of the various flash memories. The memory controller112also carries out processing to convert parallel data into serial data.

By carrying out processing in conformity with the protocol of the serial interface, the memory controller112is compatible with an existing flash memory and even with a future flash memory.

The memory controller112employs a FAT (file allocation table), for example, mounted on a personal computer, as the file management system for the flash memory111.

Moreover, the memory controller112stores a plurality of applications such as static images, dynamic images, speech, music and the like into the flash memory111, and controls the contents of the flash memory111. In this case, the memory controller112prescribes, in advance, the file format and directory management for recording data into the flash memory111by each application, and manages the data stored in the flash memory111. The memory controller112employs the DCF (Design rule for Camera File system) standardized by Japan Electronic Industry Development Association (JEIDA), as a static image format, and employs the ADPCM (Adaptive Differential Pulse Code Modulation) of the ITU-T (International Telecommunication Union) Recommendation G.726, as an audio format.

Such a radio communication device with a memory function200is loaded into the digital camera4A at the time of image shooting with the digital camera4A, and image data obtained by shooting is inputted to the memory controller112via the interface section113. Then, the memory controller112carries out processing to store the inputted image data into the flash memory111. The radio communication device with a memory function200is also loaded, for example, via the interface of a personal computer, and outputs the image data stored into the flash memory111by memory controller112via the interface section113.

The structure of the radio communication device with a memory function200is as shown inFIG. 25. In the description ofFIG. 25, portions similar to those of the radio communication device3shown inFIG. 16are denoted by the same numerals and will not be described further in detail.

As shown inFIG. 25, the interface section113of the radio communication device with a memory function200carries out input/output of a control packet and the like from/to the interface section101of the host equipment4, and is connected with a data bus and a base band control section83. The interface section101of the host equipment4is an interface corresponding to the interface section113of the radio communication device with a memory function200.

In such a radio communication device with a memory function200, the individual information and the network setting information included in a control packet are inputted from or outputted to the host equipment4by the interface section113for inputting/outputting image data.

With the radio communication device with a memory function200, for example, connection with the digital camera4A is made and image data obtained by shooting with the digital camera4A is temporarily stored into the internal flash memory111. Then, connection with the public communication network40via the portable telephone2is made by the radio communication CPU89and the image data can be transmitted as user data to an individual area of the WWW server.

Also, with the radio communication device with a memory function200, as shown inFIG. 26, when a control packet in which control data indicating “memory mode packet” as PID data is stored is inputted from the host equipment4to the radio communication CPU89in a communication idle mode (step ST1), the radio communication CPU89enters a memory mode (step ST5) for writing, reading, updating and erasing image data in the flash memory111.

In the memory mode, the radio communication CPU89controls the memory controller112to carry out processing such as writing to the flash memory111, and then returns to the communication idle mode (step ST1).

In the case where connection with the public communication network40is made via the portable telephone2, when a control packet to the effect that image data is to be transmitted to the WWW server is inputted from the host equipment4, the radio communication CPU89carries out processing to packetize image data as user data and transmit the packetized image data to the WWW server.

The processing carried out by the radio communication CPU89when connecting the host equipment4with the WWW server of the public communication network40in the wireless LAN system1having the above-described radio communication device with a memory function200will now be described with reference to the flowchart ofFIG. 27. In the description ofFIG. 27, steps ST similar to those in the foregoing flowchart are denoted by the same step numbers and will not be described further in detail.

InFIG. 27, the flash memory111of the radio communication device with a memory function200assumes that user data S0representing an image shot by the digital camera is transmitted and stored in advance in the radio communication device with a memory function200, for example, as shown inFIG. 24.

Then, the host CPU102transmits a control packet indicating an originating request S1for originating the user data from the host equipment4to the WWW server included in the public communication network40, to the radio communication CPU89.

Then, in response to the originating request S1, the host CPU102at step ST11starts the PPP stored, for example, in the ROM88.

The radio communication CPU89carries out processing to generate a control packet having the originating request and telephone number S2stored in PAYLOAD with reference to the telephone number of the Internet service provider stored in the network setting storage section86, and transmits the originating request and telephone number S2to the portable telephone2via the short distance radio communication network30.

Next, the portable telephone2transmits first call setting S3(Set up (1)) to the public network in response to the originating request and telephone number from the radio communication device with a memory function200. In response to this, the public network transmits second call setting S4(Set up (2)) having the contents similar to those of the first call setting S3, to the Internet service provider. In this case, as the Internet service provider responds, the public network is supplied with and receives first connection information S5(Connect (2)) for confirming the connection from the Internet service provider. In response to the reception of the first connection information S5, the public network transmits second connection information S6(Connect (1)) having the contents similar to those of the first connection information S5, to the portable telephone2.

The portable telephone2transmits connection completion information S7indicating that the connection with the Internet service provider is completed, to the radio communication device with a memory function200via the short distance radio communication network30.

At the next step ST12, the radio communication CPU89shifts to a link establishment phase as the PPP in response to the connection completion information S7received from the portable telephone2.

At the next step ST13, the radio communication CPU89carries out authentication processing based on the PPP. In this case, the radio communication CPU89reads out the user ID and password from the individual information storage section85and then transmits/receives authentication information S8for mutual authentication with the Internet service provider via the portable telephone2and the public network in accordance with the PPP, thus carrying out the authentication processing.

At the next step ST14, the radio communication CPU89completes the authentication processing by transmitting/receiving the authentication information S8to/from the Internet service provider, and then enters an authentication establishment phase. The radio communication CPU89outputs a control packet including connection completion information S9indicating that the connection between the radio communication device with a memory function200and the Internet service provider is completed, to the host CPU102of the host equipment4.

At the next step ST15, the radio communication CPU89shifts to a network layer protocol phase in response to the completion of the authentication processing at step ST14. That is, the radio communication CPU89makes connection with the public communication network40by using the IP and TCP mounted in the protocol stack.

At the next step ST16, the radio communication CPU89generates a control packet including the user data S0stored in the flash memory111, then packetizes the user data S0by adding control information to the user data S0in accordance with the TCP and IP, and carries out transmission/reception of packetized user data S11between the radio communication device with a memory function200and the WWW server in the public communication network40.

With the radio communication device with a memory function200, the user data stored in the flash memory111can be transmitted to and received from the public communication network40without using the host equipment4, and similarly to the foregoing radio communication device3, connection with the Internet service provider can be made by causing the radio communication CPU89to start the PPP and using the individual information and the network setting information. Thus, the network setting or the like for each host equipment for connection with the public communication network40can be simplified, and it is not necessary to provide the host equipment4with a built-in function to construct the wireless LAN system1or with a built-in function to connect to the public communication network40. Therefore, the cost of the host equipment4can be reduced.

The processing carried out by the radio communication CPU89when receiving user data from the host equipment4and transmitting the user data to the server included in the public communication network40via the portable telephone2will now be described with reference toFIGS. 28 and 29.

InFIG. 28, first, at step ST41, the radio communication CPU89sets the number of redial calls (RC) with respect to the portable telephone2to zero (RC=0).

At the next step ST42, the radio communication CPU89enters a standby state for inputting user data from the host equipment4. At the next step ST43, when it is detected by the interface section113that the user data is inputted from the host equipment4, the radio communication CPU89goes to step ST44. When the user data is not inputted from the host equipment4, the radio communication CPU89returns to step ST42and repeats steps ST42and ST43until the user data is inputted.

At step ST44, in response to the input of a control packet including the user data to the interface section113, the radio communication CPU89controls the interface section113and the memory controller112so as to store the user data into the flash memory111.

At the next step ST45, the radio communication CPU89discriminates whether or not the end of the user data received at step ST44is detected by the interface section113. When it is discriminated that the end of the user data is not detected by the interface section113, the radio communication CPU89returns to step ST44and repeats the processing of steps ST44and ST45until the end of the user data is detected by the interface section113and all the user data is stored in the flash memory111. When it is discriminated that the end of the user data is detected by the interface section113, the radio communication CPU89goes to step ST46.

At step ST46, the radio communication CPU89transmits a control packet including a control command to the effect that the power should be turned on, to the portable telephone2and thus starts the portable telephone2.

At the next step ST47, the radio communication CPU89starts the physical layer (PHY), media access control layer (MAC) and logical link control layer (LLC) stored in the ROM88, thereby establishing a link with the portable telephone2in accordance with the Bluetooth system.

At the next step ST48, the radio communication CPU89transmits the control packet including the telephone number of the Internet service provider to the portable telephone2. Thus, the radio communication CPU89controls the portable telephone2so as to make dial-up access for connecting to the Internet service provider via the portable telephone2and then goes to step ST49shown inFIG. 29.

At step ST49, the radio communication CPU89discriminates whether or not the portable telephone2completed the connection to the Internet service provider at step ST48. When it is discriminated that the portable telephone2completed the connection to the Internet service provider, the radio communication CPU89goes to step ST54. When it is discriminated that the portable telephone2did not complete the connection to the Internet service provider, the radio communication CPU89goes to step ST50. The case where the portable telephone2does not complete the connection with the Internet service provider is, for example, the case where the portable telephone2cannot receive radio waves, that is, the case where the portable telephone2is out of the radio wave reception area. In this case, a control packet indicating that the connection cannot be made is inputted to the radio communication CPU89from the portable telephone2.

At step ST50, the number of redial calls is incremented.

At the next step ST51, the radio communication CPU89discriminates whether or not a preset maximum value Rmax of the number of redial calls coincides with the number of redial calls after the increment at step ST50. When it is discriminated that the maximum value Rmax of the number of redial calls coincides with the number of redial calls after the increment, the radio communication CPU89goes to step ST62. When it is discriminated that the maximum value Rmax of the number of redial calls is not coincident with the number of redial calls after the increment at step ST50, the radio communication CPU89goes to step ST52.

At step ST52, the radio communication CPU89starts its built-in timer.

At the next step ST53, the radio communication CPU89repeats discrimination as to whether the timer started at step ST52has reached a predetermined expiration time or not. When it is discriminated that the timer has reached the expiration time, the radio communication CPU89returns to step ST46ofFIG. 28and executes the processing of step ST46and the subsequent steps again. That is, when the dial-up access to the Internet service provider cannot be established before the expiration of the timer, the radio communication CPU89repeats the processing of step ST46and the subsequent steps after the expiration of the timer.

At step ST54, which is reached by discriminating at step ST49that the portable telephone2completed the dial-up access to the Internet service provider, the radio communication CPU89starts the PPP stored in the ROM88.

At the next step ST55, the radio communication CPU89starts the PPP stored in the ROM88, then generates a control packet including the originating request and telephone number S2with reference to the telephone number of the Internet service provider, and transmits the originating request and telephone number to the portable telephone2via the short distance radio communication network30. Then, the radio communication CPU89discriminates whether the control packet to the effect that the connection is completed is inputted from the portable telephone2or not and whether the link based on the PPP is established or not. When a control packet indicating that the link based on the PPP between the portable telephone2and the Internet service provider cannot be established is inputted from the portable telephone2, the radio communication CPU89goes to step ST62. When it is discriminated that the link based on the PPP between the portable telephone2and the Internet service provider is established, the radio communication CPU89goes to step ST56.

At step ST56, the radio communication CPU89starts the TCP/IP stored in the ROM88as the network layer protocol. Thus, the radio communication CPU89makes connection with the server included in the public communication network40and establishes the link.

At the next step ST57, the radio communication CPU89starts an electronic mail application protocol such as POP3 (post office protocol 3), SMTP (simple mail transfer protocol), or IMAP (Internet message access protocol).

At the next step ST58, the radio communication CPU89transmits the user data stored in the flash memory111to the server via the portable telephone2and the Internet service provider, in conformity with the network layer protocol and the application protocol started at steps ST56and ST57.

At the next step ST59, the radio communication CPU89discriminates whether the user data transmitted at step ST58has been transmitted to the server and has ended normally or not. When it is discriminated that the user data has ended normally, the radio communication CPU89goes to step ST60. When it is discriminated that the user data has not ended normally, the radio communication CPU89goes to step ST62.

At step ST60, in response to the normal ending of the user data at step ST59, the radio communication CPU89controls the memory controller112so as to delete the user data stored in the flash memory111.

At step ST61, the radio communication CPU89controls the memory controller112so as to store a normal ending flag into a memory space of the flash memory111deleted at step ST60, and then ends the processing.

At step ST62, that is, in the case where it is discriminated at step ST51that the maximum value Rmax of the number of redial calls is coincident with the number of redial calls after the increment, or in the case where the link based on the PPP between the portable telephone2and the Internet service provider is not established, or in the case where it is discriminated at step ST59that the user data has not ended normally, the radio communication CPU89stores into the flash memory111an abnormal ending flag indicating that the user data to be transmitted to the server cannot be transmitted to the server, and then ends the processing.

In the above description of the present invention, the radio communication device3or the radio communication device with a memory function200is loaded in the host equipment4, thus transmitting/receiving user data between the host equipment4and the public communication network40. However, the radio communication device3or the radio communication device with a memory function200may also be loaded in the portable telephone2.

Such a wireless LAN system1is constituted by the portable telephone2having mounted thereon a protocol stack15including a W-CDMA layer and a HOST I/F layer as the upper layer of the W-CDMA layer, the radio communication device3having the above-described protocol stack12mounted thereon, and the host equipment4having mounted thereon a protocol stack16including a PHY layer, a MAC layer, an LLC layer, and an application layer as the upper layer for transmitting/receiving a control packet via the short distance radio communication network30, as shown inFIG. 30. In such a wireless LAN system1, the portable telephone2and the radio communication device3transmit/receive a control packet to/from each other via the HOST I/F, and the radio communication device3and the host equipment4transmit a control packet to each other via the short distance radio communication network30, thus connecting the host equipment4with the public communication network40.

In the wireless LAN system1, since the radio communication device3or the radio communication device with a memory function200is provided in the portable telephone2, similarly to the wireless LAN system1shown inFIGS. 1,2and21, the host equipment4can be connected with the Internet service provider by causing the radio communication CPU89to start the PPP and using the individual information and the network setting information, and the network setting or the like for each host equipment4to connect to the public communication network40can be simplified. Also, it is not necessary to provide the host equipment4with a built-in function to construct the wireless LAN system1and a built-in function to connect to the public communication network40, and the cost of the host equipment4can be reduced.

In the above description of the wireless LAN system1, the password for using the individual information is stored in the individual information storage section85. However, the password may also be stored in the host equipment4in order to keep security.

In such a wireless LAN system1, when connecting the host equipment4with the public communication network40via the radio communication device3or the radio communication device with a memory function200, first, a control packet containing the password is transmitted from the host equipment4to the radio communication CPU89of the radio communication device3or the radio communication device with a memory function200. Then, in response to the password inputted from the host equipment4, the radio communication CPU89discriminates whether the individual information stored in the individual information storage section85is usable or not. When it is discriminated that the individual information is usable, the radio communication CPU89starts connection with the public communication network40by using the individual information.

In the wireless LAN system1, by enabling the use of the individual information only when the password stored in the host equipment4is permitted, the security of the individual information and the network setting information stored in the radio communication device3or the radio communication device with a memory function200can be secured.

In the above-described embodiment, a PDA, a digital camera, a mail terminal, an EMD terminal and the like are used as examples of the host equipment4. However, it is a matter of course that other types of host equipments4are also applicable. By connecting the radio communication device3of the present invention to all kinds of electronic equipment, for example, a portable telephone or a game machine, and then carrying out the above-described processing, services based on the communication with the public communication network40can be provided via the short distance radio communication network30and a gateway.

With respect to the radio communication device3and the radio communication device with a memory function200in the above-described embodiment, the present invention can be applied on the basis of the physical specification and the data communication specification of various types of flash memory cards. Specifically, according to the present invention, a chip or the like for the Bluetooth system for carrying out the above-described processing can be mounted on the basis of the physical specification and the data communication specification of flash memories such as a compact flash (with a longitudinal dimension of 361 mm, a lateral dimension of 42 μm and a thickness of 3.3 mm) proposed by Sun Disk of the United States, a smart medium (with a longitudinal dimension of 45 in, a lateral dimension of 37 in and a thickness of 0.76 mm) (official name: Solid State Floppy Disk Card) proposed by Toshiba, a multimedia card (with a longitudinal dimension of 32 mm, a lateral dimension of 24 mm and a thickness of 1.4 mm) standardized by a group called Multi Media Card Association, and an SD memory card (with a longitudinal dimension of 32 μm, a lateral dimension of 24 mm and a thickness of 2.1 mm) developed by Matsushita Electric, Sun Disk of the United States, and Toshiba.

Moreover, in the above-described embodiment, radio waves of a 2.4-GHz band are transmitted/received within the short distance radio communication network30, thus connecting the host equipment4with the public communication network40. However, as a matter of course, the present invention can be applied to the case where the host equipment4is connected with the public communication network40in a home network using radio waves of a 5-GHz band, as proposed in the IEEE (Institute of Electrical and Electronics Engineers) 802.11.

INDUSTRIAL APPLICABILITY

In the communication device according to the present invention, a connection relation with a communication network is set by using communication setting information stored in storage means, and transmission/reception of data between a host equipment and an equipment included in the communication network can be controlled. Therefore, it is not necessary to carry out communication setting for connecting to the Internet or the like for each host equipment constituting a short distance radio communication network, and transmission/reception of data between the host equipment and the communication network can be simplified.

In the communication method according to the present invention, a connection relation between a communication device and a communication network via a short distance radio communication network is set by using communication setting information stored within the communication device, and transmission/reception of data is carried out between the communication device and the communication network. Also, wired supply/reception of data is carried out between a host equipment and the communication device, and transmission/reception of data is carried out between the host equipment and the communication network. Therefore, it is not necessary to carry out communication setting for connecting to the Internet or the like for each host equipment constituting the short distance radio communication network, and transmission/reception of data between the host equipment and the communication network can be simplified.

Moreover, in the communication device according to the present invention, wires communication means, short distance radio communication means, storage means, and communication control means are housed in a single casing. The wired communication means is arranged on one side of the communication control means, and the short distance radio communication means is arranged on the other side of the communication control means. Therefore, simply by loading the communication device into a host equipment, wired supply/reception of data to/from the host equipment is carried out and transmission/reception of data can be carried out between the host equipment and the communication network. Thus, with this communication device, it is not necessary to carry out communication setting for connecting to the Internet or the like for each host equipment, and transmission/reception of data between the host equipment and the communication network can be simplified.

Also, in the communication device according to the present invention, wired communication means, short distance radio communication means, storage means, and communication control means are housed in a casing having such an outer dimension that at least a part thereof can be attached to/detached from a recessed connecting section provided on a host equipment. Therefore, simply by loading the communication device into the host equipment, wired supply/reception of data to/from the host equipment is carried out and transmission/reception of data can be carried out between the host equipment and the communication network. Thus, with this communication device, it is not necessary to carry out communication setting for connecting to the Internet or the like for each host equipment, and transmission/reception of data between the host equipment and the communication network can be simplified.

Furthermore, in the communication terminal device according to the present invention, connection with a communication network is established via a public communication network by using communication setting information, and transmission/reception of data is carried out between another equipment and the communication network by using the connection relation with the communication network set by communication connection setting means. Therefore, it is not necessary to carry out communication setting for connecting to the Internet or the like for each host equipment constituting a short distance radio communication network, and transmission/reception of data between the host equipment and the communication network can be simplified.