Wireless communication system having network controller and wireless communication device connected to digital communication line, and method of controlling said system Number:6,804,195 from the United States Patent and Trademark Office (PTO) owispatent

Title: Wireless communication system having network controller and wireless communication device connected to digital communication line, and method of controlling said system

Abstract: Data communicated on one wireless channel is converted and communicated via a wired line. Alternatively, data communicated on a plurality of wireless channels is bundled and communicated via a wired line using a number of channels smaller than that of the wireless channels. In a case where another wireless communication apparatus wishes to use a wireless communication channel when a plurality of wireless channels are being used for communication, some of the plurality of wireless channels are released, thereby making it possible for the other communication apparatus to perform communication even when communication is being carried out using the plurality of wireless channels. When communication by the other wireless communication apparatus subsequently ends, communication on the original number of wireless channels is resumed.

Patent Number: 6,804,195 Issued on 10/12/2004 to Izumi,   et al.

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Inventors:	Izumi; Michihiro (Yokohama, JP); Kagaya; Naoto (Yokohama, JP); Arai; Shunji (Yokohama, JP); Uchimi; Akihiro (Tokyo, JP)
Assignee:	Canon Kabushiki Kaisha (Tokyo, JP)
Appl. No.:	09/005,928
Filed:	January 12, 1998

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Foreign Application Priority Data

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Jan 14, 1997 [JP]			9-017472
Jul 24, 1997 [JP]			9-214020

Current U.S. Class:	370/230 ; 370/264; 370/466
Field of Search:	370/220,522,524,465,347,451,433,466,467,493,480,468,401,349,328,329,338 455/517,465,450,507,509,511

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References Cited [Referenced By]

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U.S. Patent Documents

	5519702		May 1996		Takahashi
	5591702		January 1997		Murphy
	5602837		February 1997		Takahashi
	5757788		May 1998		Tatsumi et al.
	6018520		January 2000		Okada
	6028845		February 2000		Serikawa et al.

Primary Examiner: Ho; Duc
Attorney, Agent or Firm: Morgan & Finnegan, LLP

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Claims

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What is claimed is:

1. A communication system having a control apparatus connectable to a wired line, and a first wireless communication apparatus wirelessly connectable to the control apparatus, wherein said control apparatus comprises: first wireless communication means for communicating data with the first wireless communication apparatus using plural N wireless channels of plural M (M.gtoreq.N) wireless channels; first converting means for converting data on the plural N wireless channels received by said first wireless communication means to data for a wired channel; and wired communication means for communicating, via the wired channel of the wired line, the data obtained by the conversion performed by said first converting means, and said first wireless communication apparatus comprises: second wireless communication means for communicating data with said control apparatus using plural N wireless channels of plural M wireless channels, wherein said first wireless communication means can release a number of N wireless channels which have been used for data communication for other communication, and said first converting means performs data conversion without changing said wired channel even if the number of wireless channels is released.

2. The system according to claim 1, wherein said control apparatus has control means for releasing some of the plural N wireless channels being used by said first wireless communication means if a call origination request is received from another communication apparatus when communication is being performed by said first wireless communication means and said wired communication means.

3. The system according to claim 2, wherein said control means uses the released channels for communication with said other communication apparatus.

4. The system according to claim 3, wherein when communication with said other communication apparatus is finished, said control means uses the wireless channels that were used for communication with said other communication apparatus for communication with said first wireless communication apparatus.

5. The system according to claim 2, wherein when the wireless channels are released, said control means transmits information, which notifies of a change in transmission speed of data communicated using said wired communication means, to said wired line.

6. The system according to claim 2, wherein said other communication apparatus is a second wireless communication apparatus with which said control apparatus is capable of wirelessly communicating.

7. The system according to claim 2, wherein said other communication apparatus is a communication apparatus capable of communicating via the wired line.

8. The system according to claim 1, wherein said first wireless communication apparatus has connecting means for connecting a data processing device that is capable of data communication, and said second wireless communication means communicates data received from said data processing device via said connecting means.

9. The system according to claim 1, wherein said first and second wireless communication means perform communication using two wireless channels of plural M wireless channels; said first converting means converts data on two of the wireless channels to data on one channel; and said wired communication means communicates the data, obtained by the conversion by said first converting means, on one channel.

10. The system according to claim 1, wherein said first wireless communication means is capable of communication by using a single wireless channel of plural M wireless channels, and said control apparatus determines the number of wireless channels in dependence upon a command from said first wireless communication apparatus.

11. The system according to claim 10, wherein the command is issued when said first wireless communication apparatus issues a call origination request to said control apparatus.

12. The system according to claim 11, wherein the command is included in information added onto dialing information transmitted when said first wireless communication apparatus issues the call origination request to said control apparatus.

13. A control apparatus, connectable to a wired line, capable of being wirelessly connected to a first wireless communication apparatus, comprising: first wireless communication means for communicating data with the first wireless communication apparatus using plural N wireless channels of plural M (M.gtoreq.N) wireless channels; first converting means for converting data on the plural N wireless channels received by said first wireless communication means to data for a wired channel that the channel number differs from the number of wireless channels; and wired communication means for communicating, via the wired channel of the wired line, the data obtained by the conversion performed by said first converting means, wherein said first wireless communication means can release a number of N wireless channels which have been used for data communication for other communication, and said first converting means performs data conversion without changing wired channels even if the number of wireless channels is released.

14. The apparatus according to claim 13, wherein said control apparatus has control means for releasing some of the plural N wireless channels being used by said first wireless communication means if a call origination request is received from another communication apparatus when communication is being performed by said first wireless communication means and said wired communication means.

15. The apparatus according to claim 14, wherein said control means uses the released channels for communication with said other communication apparatus.

16. The apparatus according to claim 15, wherein when communication with said other communication apparatus is finished, said control means uses the wireless channels that were used for communication with said other communication apparatus for communication with said first wireless communication apparatus.

17. The apparatus according to claim 14, wherein when the wireless channels are released, said control means transmits information, which notifies of a change in transmission speed of data communicated using said wired communication means, to said wired line.

18. The apparatus according to claim 14, wherein said other communication apparatus is a second wireless communication apparatus with which said control apparatus is capable of wirelessly communicating.

19. The apparatus according to claim 14, wherein said other communication apparatus is a communication apparatus capable of communicating via the wired line.

20. The apparatus according to claim 13, wherein said first wireless communication means performs communication using two wireless channels of plural M wireless channels; said first converting means converts data on two of the wireless channels to data on one channel; and said wired communication means communicates the data, obtained by the conversion by said first converting means, on one channel.

21. The apparatus according to claim 13, wherein said first wireless communication means is capable of communication by using a single wireless channel of plural M wireless channels, and said control apparatus determines the number of wireless channels in dependence upon a command from said first wireless communication apparatus.

22. The apparatus according to claim 21, wherein the command is issued when said first wireless communication apparatus issues a call origination request to said control apparatus.

23. The apparatus according to claim 22, wherein the command is included in information added onto dialing information transmitted when said first wireless communication apparatus issues the call origination request to said control apparatus.

24. A wireless communication apparatus, capable of wireless communication with a first communication apparatus, which performs communication with a second communication apparatus via wired channels, comprising; wireless connection means for wirelessly connecting with said first communication apparatus via N wireless channels of plural P (P.gtoreq.N) wireless channels, wherein said first communication apparatus performs communication via a wired channel; and wireless communication means for communicating data, which is communicated via the wired channel by said first communication apparatus, with said first communication apparatus via the N wireless channel, wherein said wireless connection means releases a number of N wireless channels connected to said first communication apparatus while said first communication apparatus is communicating data for other communication with said second communication apparatus via the wired channel, and said wireless communication means communicates data, which was communicated via the wired channel by said first communication apparatus, with said first communication apparatus via wireless channels that the wireless channels has been released.

25. The apparatus according to claim 24, wherein said wireless connection means releases some of the N wireless channels, which have been connected with said first communication apparatus, in accordance with a signal received from said first communication apparatus.

26. The apparatus according to claim 25, wherein said wireless connection means connects the released wireless channels again in accordance with the signal received from said first communication apparatus.

27. The apparatus according to claim 24, wherein said wireless communication apparatus has connecting means for connecting a data processing device that is capable of data communication, and said wireless communication means communicates data from said data processing device received via said connecting means.

28. The apparatus according to claim 24, wherein said wireless communication means performs communication using two wireless channels of plural P wireless channels; and said first communication apparatus converts data on two of the wireless channels to data on one channel and communicates with the data, obtained by the conversion, on one channel.

29. The apparatus according to claim 24, wherein said wireless communication apparatus transmits information for specifying the number of wireless channels for connecting with said first communication apparatus upon start of communication with said first communication apparatus.

30. The apparatus according to claim 29, wherein said information is added onto dialing information and transmitted.

31. A method of controlling a communication system having a control apparatus connectable to a wired line, and a first wireless communication apparatus wirelessly connectable to the control apparatus, wherein a method of controlling said control apparatus comprises: a first wireless communication step of causing communication of data with the first wireless communication apparatus using plural N wireless channels of plural M (M.gtoreq.N) wireless channels; a first converting step of converting data on the plural N wireless channels received at said first wireless communication step to data for a wired channel; and a wired communication step of causing communication of data, via the wired channel of the wired line, obtained by the conversion performed at said first converting step, and a method of controlling said first wireless communication apparatus comprises: a second wireless communication step of causing communication of data with said control apparatus using plural N wireless channels of plural M wireless channels, wherein the number of N wireless channels can be released at said first wireless communication step which have been used for data communication for other communication, and data conversion is performed at said first converting step without changing said wired channel even if the number of wireless channels is released.

32. A method of controlling a control apparatus, which is connectable to a wired line, capable of being wirelessly connected to a first wireless communication apparatus, comprising: a first wireless communication step of causing communication of data with the first wireless communication apparatus using plural N wireless channels of plural M (M.gtoreq.N) wireless channels; a first converting step of converting data on the plural N wireless channels received at said first wireless communication step to data for a wired channel; and a wired communication step of causing communication of data, via the wired channel of the wired line, obtained by the conversion performed at said first converting step, wherein a number of N wireless channels can be released at said first wireless communication step which have been used for data communication for other communication, and data conversion is performed at said first converting step without changing said wired channel even if the number of wireless channels is released.

33. A method of controlling a wireless communication apparatus capable of wireless communication with a first communication apparatus, which performs communication with a second communication apparatus via wired channels, comprising; a wireless connection step of wirelessly connecting with said first communication apparatus via N wireless channels of plural P (P.gtoreq.N) wireless channels, wherein said first communication apparatus performs communication via a wired channel; and a wireless communication step of causing communication of data, which is communicated via the wired channel by said first communication apparatus, with said first communication apparatus via the N wireless channels, wherein a number of N wireless channels connected to said first communication apparatus is released at said wireless connection step while said first communication apparatus is communicating with said second communication apparatus via the wired channel which have been used for data communication for other communication, and said wireless communication step causes communication of data, which was communicated via the wired channel by said first communication apparatus, with said first communication apparatus via wireless channels that wireless channels has been released.

34. A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for controlling a control apparatus, which is connectable to a wired line, capable of being wirelessly connected to a first wireless communication apparatus, said method comprising; a first wireless communication step causing communication of data with the first wireless communication apparatus using plural N wireless channels of plural M (M.gtoreq.N) wireless channels; a first converting step converting data on the plural N wireless channels received at said first wireless communication step to data for a wired channel; and a wired communication step causing communication of data, via the wired channel of the wired line, obtained by the conversion performed at said first converting step, wherein a number of N wireless channels can be released at said first wireless communication step which have been used for data communication for other communication, and data conversion is performed at said first converting step without changing said wired channel even if the number of wireless channels is released.

35. A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform method steps for controlling a wireless communication apparatus capable of wireless communication with a first communication apparatus, which performs communication with a second communication apparatus via wired channels, said method comprising: a wireless connection step wirelessly connecting with said first communication apparatus via N wireless channels of plural P (P.gtoreq.N) wireless channels, wherein said first communication apparatus performs communication via a wired channel; and a wireless communication step causing communication of data, which is communicated via the wired channel by said first communication apparatus, with said first communication apparatus via the N wireless channels step, wherein a number of N wireless channels connected to said first communication apparatus is released at said wireless connection step while said first communication apparatus is communicating with said second communication apparatus via the wired channel which have been used for data communication for other communication, and said wireless communication step causes communication of data, which was communicated via the wired channel by said first communication apparatus, with said first communication apparatus via wireless channels that the wireless channels has been released.

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Description

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BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a wireless communication system having a network controller and a wireless communication device connected to a digital communication line, as well as to a method of controlling this system.

2. Description of the Related Art

A system available in the art wirelessly connects a network controller and a wireless communication device, which are connected to an ISDN (Integrated Services Digital Network), by using a digital cordless telephone in accordance with the standard of the PHS (Personal Handyphone System) employed in Japan.

With a system of this kind, two wireless communication devices are capable of communicating using B1 and B2 channels of an ISDN one at a time. For example, one wireless communication device communicates using the B1 channel of the ISDN and the other wireless communication device communicates using the B2 channel of the ISDN.

Though a digital cordless telephone such as one in accordance with the PHS standard communicates using a wireless communication frame in which a plurality of wireless channels are time-division multiplexed, one wireless communication device communicates using one wireless channel. In other words, in a case where connections are made to an ISDN in the manner described above, the data on one wireless channel is communicated using one channel of the ISDN.

However, with PHS, for example, the transmission speed of one wireless channel is 32 kbps while the transmission speed of one channel of the ISDN is 64 kbps. This means that the transmission speed of a 64-kbps ISDN cannot be utilized effectively.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to perform wireless communication utilizing the channels of a wired line effectively.

Another object of the present invention is to perform communication by bundling together the data on two wireless channels and using one channel of a wired line.

A further object of the present invention is to utilize the channels of a wired line effectively without interfering with the wireless communication of another communication device.

Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing the configuration of a system according to a first embodiment of the present invention;

FIG. 2 is a block diagram showing a wireless terminal adapter according to the first embodiment;

FIG. 3 is a block diagram of a wireless PC card according to the first embodiment;

FIG. 4 is a diagram showing the format of a time-division multiplexed wireless communication frame used in the first embodiment;

FIG. 5 is a diagram showing a communication sequence of a wireless link and ISDN line according to the first embodiment;

FIG. 6 is a flowchart showing the operation of the first embodiment;

FIG. 7 is a block diagram showing a wireless terminal adapter according to a first embodiment of the present invention;

FIG. 8 is a block diagram of a wireless PC card according to the second embodiment;

FIG. 9 is a block diagram of a wireless PC card according to the second embodiment;

FIG. 10 is a block diagram showing a wireless terminal adapter according to a sixth embodiment of the present invention;

FIG. 11 is a diagram showing the configuration of a system according to a seventh embodiment of the present invention;

FIG. 12 is a block diagram showing wired communication device according to the seventh embodiment;

FIG. 13 is a block diagram showing a wireless communication terminal according to the seventh embodiment;

FIG. 14 is a block diagram of an ISDN communication terminal according to the seventh embodiment;

FIGS. 15A-15C are diagrams showing the structure of wireless frames according to the seventh embodiment;

FIG. 16 is a data communication sequence according to the seventh embodiment;

FIG. 17 is a flowchart showing the wireless connection operation according to the seventh embodiment;

FIG. 18 is a flowchart showing the data communication operation of the wired communication device according to the seventh embodiment;

FIG. 19 is a flowchart showing the data communication operation of the ISDN communication terminal according to the seventh embodiment;

FIGS. 20A and 20B are diagrams useful in describing data transmission according to the seventh embodiment;

FIG. 21 is a diagram showing the configuration of a system according to an eighth embodiment of the present invention;

FIG. 22 is a block diagram showing a slave device in the wireless communication system of the eighth embodiment;

FIG. 23 is a block diagram showing a master device in the wireless communication system of the eighth embodiment;

FIG. 24 is a flowchart showing the operation of the wireless communication system of the eighth embodiment;

FIG. 25 is a diagram showing the configuration of a system according to a ninth embodiment of the present invention;

FIG. 26 is a block diagram showing a PHS slave device according to the ninth embodiment;

FIG. 27 is a block diagram showing a facsimile communication device according to the ninth embodiment;

FIG. 28 is a data communication sequence according to the ninth embodiment;

FIG. 29 is a data communication sequence according to the ninth embodiment;

FIG. 30 is a flowchart showing the operation of the facsimile communication device according to the ninth embodiment;

FIG. 31 is a flowchart showing the operation of the facsimile communication device according to the ninth embodiment;

FIG. 32 is a flowchart showing the operation of the facsimile communication device according to the ninth embodiment;

FIG. 33 is a flowchart showing the operation of the PHS slave device according to the ninth embodiment;

FIG. 34 is a flowchart showing the operation of the PHS slave device according to the ninth embodiment;

FIG. 35 is a flowchart showing the operation of the PHS slave device according to the ninth embodiment; and

FIGS. 36A-36C are diagrams showing the structure of wireless frames according to the ninth embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Embodiment

FIG. 1 is an explanatory view illustrating the configuration of a wireless communication system according to a first embodiment of the present invention. In this embodiment, a PHS telephone will be described as an example of a digital cordless telephone. The wireless communication system includes a wireless terminal adapter 102 connected to an ISDN 101 and corresponding to a network controller, a personal computer (PC) 103 equipped with a wireless PC card 104 and wirelessly linked to the wireless terminal adapter 102, and a wireless telephone 105.

The wireless terminal adapter 102 accommodates an ISDN line and, at the same time, functions as a PHS master device, converts voice and data, which have been transmitted from a PHS wireless terminal, to voice and data having the transmission speed of the ISDN and transmits the converted voice and data to the ISDN.

FIG. 2 is a block diagram showing the construction of the wireless terminal adapter 102 according to the first embodiment.

The wireless terminal adapter 102 includes a CPU 201 for controlling the overall device in accordance with a program that has been stored in a memory 202, the memory 202 storing various programs and data, a data bus 203 for transferring data, an ISDN interface 205 which allows the connection of an ISDN line 204, a multiplexer 206 for changing over data connected to B1/B2 channels of the ISDN interface 205, a speed converter 207 which converts 32-kbps data to 64-kbps data in accordance with I.460, a data multiplexer 208 for multiplexing data transmitted on two wireless channels and converting the data to 64-kbps data, an ADPCM/PCM converter 209 for converting between ADPCM (Adaptive Differential Pulse Code Modulation) data and PCM (Pulse Code Modulation) data, a switch 210 for changing over data sent and received on each wireless channel, a channel codec 211 which executes frame processing of transmission data, a wireless module 212 for performing wireless transmission, and an antenna 213.

FIG. 3 is a block diagram showing the construction of the wireless PC card 104 according to the first embodiment.

The wireless PC card 104 includes a CPU 301 for controlling the overall device in accordance with a program that has been stored in a memory 302, the memory 302 storing various programs and data, a data bus 303 for transferring data, a PC card interface 305 for connecting a PC card bus 304, a first parallel/serial converter 306, a second parallel/serial converter 307, a channel codec 308, a wireless module 309 and an antenna 310.

FIG. 4 is an explanatory view illustrating a transmission frame format of a wireless channel.

According to the format, the transmission frame has four channels for transmission and four channels for reception. Among these channels, first channels indicated by TC/RC are used as channels for control. The wireless terminal adapter 102, wireless PC card 104 and wireless telephone 105 are set to the control channel frequency in the first channel.

The other wireless channels T2, T3, T4, R2, R3, R4 are used voice or data communication and the transmission speed of each of these channels is 32 kbps.

FIG. 5 is an explanatory view showing the communication sequence of a wireless link and ISDN line according to the first embodiment, and FIG. 6 is a flowchart showing operation in a case where the PC in the first embodiment starts/stops a call from a wireless telephone.

Operation will be described in a case where the PC 103 performs communication using two wireless channels simultaneously and the wireless telephone 105 starts voice communication during a data transmission.

First, the operator performs a dialing operation by starting up communication application software in the PC 103 (S601). If the application software recognizes the origination request, then the application starts up a wireless PC card driver for performing communication using the wireless PC card 104 (S602). In accordance with an indication from the PC 103, the CPU 301 of the wireless PC card 104 transmits a call set-up message to the wireless terminal adapter 102. At this time a call set-up message corresponding to each channel is transmitted (S603) to perform communication using two wireless channels simultaneously.

By receiving the two call set-up messages from the wireless PC card 104 (S604), the CPU 201 of the wireless terminal adapter 102 recognizes the data transmission that employed the two channels and effects the connection to the other party's terminal by executing ISDN origination processing. At this time a transmission-capability information element in the call set-up message to the ISDN is set in such a manner that 64-kbps unrestricted digital information is transmitted (S605).

If the called terminal responds and an answer message is received (S606), the CPU 201 of the wireless terminal adapter 102 transmits the answer message to the wireless PC card 104 (S607). The PC 103 presents a display to the effect that the connection has been completed (S608) and then starts the transmission of data sent to the called party connected via the ISDN.

The wireless PC card driver writes the transmission data to the memory 302 of the wireless PC card 104. The transmission speed of this data is 64 kbps, which allows the transmission speed of the B channel of the ISDN to be exploited to the maximum degree. When the CPU 301 reads the transmission data out of the memory 302, it divides the data into two data streams each corresponding to a transmission speed of 32 kbps and delivers the data streams to the parallel/serial converters 306, 307 of the first and second channels. The two streams of data are each written to the channel codec 308. The latter assembles the transmission data into time-division multiplexed frame format and transmits this data to the wireless terminal adapter 102 using the two 32-kbps T2 and T4 channels. Thus, 64-kbps data is transmitted from the wireless PC card 104.

Upon receiving the data via these two channels, the CPU 201 of the wireless terminal adapter 102 causes the data multiplexer 208 to multiplex the two streams of serial data output by the channel codec 211 at 32 kbps and to convert the data to a single stream of 64-kbps serial data. The CPU 201 transmits the 64-kbps serial data to the ISDN interface 205 via the multiplexer 206. The ISDN interface 205 assembles the data into an ISDN frame and transmits the 64-kbps data, which has been sent from the PC, on the B1 channel (S609).

The data received from the called terminal is transmitted in the opposite direction while undergoing a similar speed conversion. More specifically, 64-kbps data received via the ISDN interface 205 is disassembled into two streams of 32-kbps serial data in the data multiplexer 208 and the data then enters the channel codec 211. The two streams of 32-kbps serial data are transmitted to the wireless PC card using the R2 and R4 channels of the wireless channels. The two-streams of 32-kbps data output by the channel codec 308 are multiplexed to 64-kbps data in the wireless PC card 104 and the multiplexed data is sent to the PC 103. Thus, it is possible to transmit data at 64 kbps, which is twice the transmission speed of the prior art.

It is also possible for the wireless telephone 105 to perform voice communication via the ISDN while the PC 103 is carrying out data communication at the high speed of 64 kbps. When a dialing operation is performed at the wireless telephone 105 (S610), call origination processing is executed by the control channels TC, RC in regard to the wireless terminal adapter 102 in accordance with the above-described control sequence of FIG. 5 in the same manner as the wireless PC card 104.

When the wireless terminal adapter 102 senses that the T2/R2 channels and T4/R4 channels are already being used in communication with the wireless PC card 104 (S611), the wireless terminal adapter 102 sends the wireless PC card 104 a disconnect message in regard to the T4 channel (S612).

As a result, the CPU 301 of the wireless PC card 104 recognizes that it is necessary to release the T4 channel being used and transmits a release message to the wireless terminal adapter 102. Upon receiving the release message from the wireless PC card 104 (S613), the CPU 201 of the wireless terminal adapter 102 notifies the other party's terminal, via the ISDN, of the fact that the 64-kbps transmission has been changed over to a transmission in accordance with I.460 based upon 32 kbps (S614). This is performed utilizing a user-user signal connection.

Upon receiving the request for opening the T4 channel, the CPU 301 of the wireless PC card 104 performs control so as to halt the transmission of one of the two 32-kbps data streams and in such a manner that the channel codec 308 performs data transmission using solely the T2 channel (S615).

After the above-described processing is executed, the wireless terminal adapter 102 sends the wireless telephone 105 a call set-up acceptance message and, at the same time, sends the ISDN a call set-up message indicating that voice communication is performed via the B2 channel (S616). If the other party's terminal responds and an answer message is received from the ISDN (S617), the wireless terminal adapter 102 transmits the answer message to the wireless telephone 105 on the control channel and the wireless telephone 105 is connected to the other party's terminal.

After the connection is made, the wireless telephone 105 communicates 32-kbps ADPCM data with the wireless terminal adapter 102 using the T4, R4 channels.

The CPU 201 of the wireless terminal adapter 102 performs control so as to change over the changeover switch 210 so that the T4 channel is connected to the ADPCM/PCM converter 209. As a result, the received 32-kbps ADPCM data is converted to 64-kbps PCM data and transmitted via the B2 channel of the ISDN (S618).

Further, the voice received on the B2 channel of the ISDN is transmitted to the wireless telephone 105 via the wireless terminal adapter 102. The ADPCM data is converted to analog data in the wireless telephone 105 and the analog data is output as audio.

Next, if the wireless telephone 105 has completed voice communication (S619), it is possible for the wireless PC card 104 to perform high-speed data communication again using two channels.

If communication by the wireless telephone 105 is completed and a T4-channel disconnect message is sent to the wireless terminal adapter 102, the latter transmits the disconnect message to the ISDN and disconnects the B2 channel (S620). The wireless terminal adapter 102 transmits an incoming-call message to the wireless PC card 104 to notify it of the fact that the T4 channel can be used (S621).

Upon receiving this notification, the wireless PC card 104 transmits a call answer message (S622) in order to acquire the right to use the T4 channel. Upon verifying that there is no a request to use the wireless channel from another terminal, the wireless terminal adapter 102 transmits a transmission-capability information element to the other party's terminal via the ISDN by means of a user-user signal connection to notify the terminal of the fact that the data transmission speed will be changed from 32 kbps to 64 kbps (S623).

Thereafter, the wireless terminal adapter 102 sends the wireless PC card 104 an answer message and, upon receiving the answer message, the wireless PC card 104 starts 64-kbps data transmission using the T2 and T4 channels simultaneously (S624).

The description above deals with processing in a case where the wireless telephone 105 has issued a call origination request while the wireless PC card 104 is executing data communication. However, similar processing would be executed also in a case where an incoming call arrives at the wireless telephone 105 from ISDN while the wireless PC card 104 is performing communication.

After it receives the call set-up message from the ISDN, the wireless terminal adapter 102, upon sending the ISDN a call set-up acceptance message, transmits a T4-channel disconnect message to the wireless PC card 104 to request release of the T4 channel. Upon receiving a confirmation message for releasing the T4 channel from the wireless PC card 104, the wireless terminal adapter 102 notifies the other party's terminal, via the ISDN, of the fact that the 64-kbps transmission has been changed over to a transmission in accordance with I.460 based upon 32 kbps. This is performed utilizing a user-user signal connection.

When one wireless channel is released, the wireless terminal adapter 102 transmits a call set-up message to the wireless telephone 105 to notify it of the incoming call. Upon receiving the answer message from the wireless telephone 105, the wireless terminal adapter 102 transmits the answer message to the ISDN, after which the wireless telephone 105 is capable of starting voice communication.

Thus, during the time that the wireless PC card 104 is wirelessly accessing the wireless terminal adapter 102, it is possible for the wireless telephone 105 to use a wireless channel in a case where a request for start of voice communication by the wireless telephone 105 is issued even while the wireless PC card 104 is performing 64-kbps high-speed data transmission using two channels.

When communication by the wireless telephone 105 is finished, it is possible for high-speed data communication is be performed again using two channels.

Second Embodiment

A second embodiment of the present invention will be described next.

In data communication according to the first embodiment, data transmitted from the wireless PC card 104 is converted as is to 64-kbps data and transmitted to the ISDN without buffering being carried out within the wireless terminal adapter 102.

However, it is possible to obtain similar results even is buffering is performed in packet units within the wireless terminal adapter 102. An advantage here is that even if the number of wireless channels used changes and there is a change in the transmission speed over the wireless link, it is unnecessary to change the transmission-performance information element between the device and the other party connected via the ISDN.

More specifically, it is possible to deal with a change in data transmission speed by fixing the transmission-performance information element at 64-kbps unlimited digital information and by judging in the other party's terminal that valid data has been received after the packet header is sensed.

FIG. 7 is a block diagram illustrating the construction of the wireless terminal adapter 102 according to a second embodiment of the present invention.

The wireless terminal adapter 102 includes a CPU 701 for controlling the overall device in accordance with a program that has been stored in a memory 702, the memory 702 storing various programs and data, a data bus 703 for transferring data, an ISDN interface 705 which allows the connection of an ISDN line 704, a multiplexer 706 for changing over data connected to B1/B2 channels of the ISDN interface 705, a multiplexer 706 for changing over data connected to B1/B2 channels of the ISDN interface 705, an HDLC (High-level Data Link Control) controller 707 for assembling/disassembling HDLC packets transmitted by the ISDN, first and second HDLC controllers 708, 709 for assembling/disassembling HDLC packets transmitted by the wireless link, an ADPCM/PCM converter 710 for converting ADPCM data to PCM data, a switch 711 for changing over data sent and received on each wireless channel, a channel codec 712 which executes frame processing of transmission data, a wireless module 713 for performing wireless transmission, and an antenna 714.

FIG. 8 is a block diagram showing the construction of the wireless PC card 104 according to the second embodiment.

The wireless PC card 104 includes a CPU 801 for controlling the overall device in accordance with a program that has been stored in a memory 802, the memory 802 storing various programs and data, a data bus 303 for transferring data, a PC card interface 805 for connecting the PC card bus 804, first and second HDLC controllers 806, 807 for assembling/disassembling HDLC packets transmitted by the ISDN, a channel codec 808 for executing transmission-data frame processing, a wireless module 809 for performing wireless transmission, and an antenna 810.

When data is transmitted by the wireless PC card 104, data is written from memory to the HDLC controllers 806, 807 and is assembled into an HDLC frame format to which a flag, address, CRC, etc., have been attached. At this time data transmitted on the T2 channel is assembled by the first HDLC controller 806 and data transmitted on the T4 channel is assembled by the second HDLC controller 807.

Upon receiving packets on the T2 and T4 channels, the wireless terminal adapter 102 transfers the received packets to the memory 702 via the HDLC controllers 708, 709 on respective channels and requests re-transmission with regard to any packets found to be erroneous by a CRC check. Moreover, the wireless terminal adapter 102 rearranges the packets in the order to packet numbers attached to the data field and sends the HDLC controller 707 the data to be transmitted to the ISDN. The data that has been assembled into the prescribed frame is transmitted to the ISDN by the HDLC controller 707 via the ISDN interface 705.

The transmission speed of the data sent from the wireless PC card 104 is 32 kbps on each channel. Accordingly, if the transmission speed of the data following the rearrangement of the packets by the wireless terminal adapter 102 is less than 64 kbps and a buffer memory having a capacity which takes into account packets whose arrival is delayed by retransmission control is provided, it will be possible to transmit data to the ISDN without causing data overflow.

In a case where the wireless telephone 105 starts voice communication when data communication is thus being performed using two channels, the wireless PC card 104 is notified of a request for release of the wireless channel T4 through a procedure similar to that of the first embodiment.

From this point onward the wireless PC card 104 modifies processing so as to send the transmission data solely to the first HDLC controller 806. The wireless terminal adapter 102 performs control to change over the changeover switch 711 so that the data on the T4 channel is connected to the ADPCM/PCM converter 710.

Thus, voice communication can begin even during data communication using a plurality of channels.

Third Embodiment

A third embodiment will now be described.

In the first embodiment, the data transmission speed is 32 kbps or 64 kbps. However, the same results can be obtained even with low-speed (e.g., 19.2 kbps) data. In the case of such low-speed data, it is necessary to insert redundant data within the wireless PC card 104 in accordance with a conversion method stipulated by ITU-T recommendation V.110 and convert 19.2 kbps to 32 kbps.

FIG. 9 is a block diagram showing the construction of the wireless PC card 104 according to the third embodiment.

The wireless PC card 104 includes a CPU 901 for controlling the overall device in accordance with a program that has been stored in a memory 902, the memory 902 storing various programs and data, a data bus 903 for transferring data, a PC card interface 905 for connecting a PC card bus 904, a first V.110 speed converter 906 and a second V.110 speed converter 907 for converting data having a transmission speed less than 32 kbps to data having a transmission speed of 32 kbps, a channel codec 908 for executing transmission-data frame processing, a wireless module 909 for performing wireless transmission, and an antenna 910.

Operation according to the third embodiment is the same as that of the first embodiment with the exception of the fact that transmission data is written from the memory 902 to the V.110 speed converters 906, 907 and data that has been converted to the speed of 32 kbps by the V.110 speed converters 906, 907 enters the channel codec 908.

Fourth Embodiment

A fourth embodiment will be described next.

A wireless telephone is assumed to be the second wireless terminal in the first embodiment. However, the same effects can be obtained even if the second wireless terminal is a wireless PC card which performs data communication in a manner similar to that of the first wireless terminal.

In a case where the two terminals communication simultaneously, each performs a 32-kbps transmission utilizing one channel each. When communication by one terminal is completed, the other terminal performs 64-kbps transmission utilizing two channels.

Fifth Embodiment

A fifth embodiment will now be described.

In the first embodiment, it is assumed that the wireless link is a PHS wireless link in which the transmission speed of one channel is 32 kbps. However, similar operation is possible even with other types of wireless communication links. For example, data transmission at higher speed can be realized using spread spectrum communication.

Further, in case of a higher speed wireless channel, it is possible to increase the number of wireless channels. When high-speed data communication is performed in such case, eight channels, for example, are used. When communication requests are issued by another terminals, control is performed so as to release the channels one at a time, thereby making it possible to utilize wireless channels efficiently.

Sixth Embodiment

A sixth embodiment will be described next.

In the first embodiment, only one channel of the ISDN is used in data communication. However, in a case where the overall transmission speed of the wireless link is large, as in the fifth embodiment, more effective utilization of the link can be achieved by combining bulk transfer of the B1 and B2 channels of the ISDN.

The sixth embodiment will be described for a case where the number of wireless channels (other than control channels) having a transmission speed of 32 kbps is eight in both directions (four 128-kbps channels in one direction).

FIG. 10 is a block diagram illustrating the construction of the wireless terminal adapter 102 according to the sixth embodiment.

The wireless terminal adapter 102 includes a CPU 1001 for controlling the overall device in accordance with a program that has been stored in a memory 1002, the memory 1002 storing various programs and data, a data bus 1003 for transferring data, an ISDN interface 1005 which allows the connection of an ISDN line 1004, a multiplexer 1006 for changing over data connected to B1/B2 channels of the ISDN interface 1005, a multiplexer 1006 for changing over data connected to B1/B2 channels of the ISDN interface 1005, an HDLC controller 1007 for the B1 channel, an HDLC controller 1008 for the B2 channel, HDLC controllers 1009.about.1012 for assembly and disassembling HDLC packets transmitted on four channels of the wireless link, an ADPCM/PCM converter 1013 for converting ADPCM data to PCM data, a switch 1014 for changing over data sent and received on each wireless channel, a channel codec 1015 which executes frame processing of transmission data, a wireless module 1016 for performing wireless transmission, and an antenna 1017.

If the personal computer performs data communication in the arrangement described above, transmission is carried out at 128 kbps, which corresponds to B1, B2 bulk transfer of the ISDN, using all wireless channels. In a manner similar to that of the second embodiment, the wireless terminal adapter 102 disassembles packets on respective channels using the HDLC controllers 1009.about.1012, rearranges the data in the order of the packet numbers and stores the data in the memory 1002. Next, HDLC frames are re-assembled by the HDLC controllers 1007, 1008 and the frames are transmitted on respective B1, B2 channels.

Thus, in a case where a call is originated by the wireless telephone 105 or a call from the ISDN is terminated at the wireless telephone 105 when bulk transfer is being performed at 128 kbps, the wireless PC card 104 is notified of a request for release of the wireless channel through a procedure similar to that of the second embodiment, the B2 channel of the ISDN is released and, at the same time, control is performed in such a manner that only two wireless channels are used.

The data communication operation from this point onward is the same as that in the second embodiment for the case where two wireless channels are used, and a state is attained in which the HDLC controllers 1008, 1011 and 1012 are not used.

Thus, while communication is performed at a speed that corresponds to the maximum transmission speed of the ISDN in a case where communication is carried out solely by a data communication terminal, it is possible, when it becomes necessary for another terminal to communicate, to release some slots of the wireless link and one channel of the ISDN to this other terminal. This makes it possible to utilize the communication link effectively.

Seventh Embodiment

A seventh embodiment will now be described.

In order to use the wireless channels and ISDN channel efficiently, this embodiment provides an arrangement for matching the speeds of a plurality of wireless channels and one ISDN channel.

FIG. 11 is a diagram showing the configuration of a system according to this embodiment.

This system comprises a wired communication device 1101 having a PHS wireless communication function and connected to an ISDN public line, a wireless communication terminal 1102 having a PHS wireless communication function 1102 and a multimedia communication function, an ISDN communication terminal 1103 connected to the ISDN public line and having and having a multimedia communication function, and an ISDN public line network 1104.

FIG. 12 is a block diagram showing the construction the wired communication device 1101.

The wired communication device 1101 includes a CPU 1201 which is the nucleus of the device 1101 and supervises control of the overall device inclusive of its components and wireless controller in accordance with programs stored in a ROM 1202. The latter stores the control program of the CPU 1201. A RAM 1203 stores various data for controlling the CPU 1201 and provides a working area for various arithmetic operations.

A speed converter 1204 performs a speed conversion to convert 32-kbps data from the PHS wireless link to 64-kbps data for the ISDN line, bundling the data of two PHS channels onto one ISDN channel and, conversely, disassembling data. A call set-up message analyzer 1205 analyzes a call set-up message received from the PHS wireless link or ISDN line. A call set-up message creating unit 1206 creates a call-set up message sent to the PHS wireless link or ISDN line.

A radio unit 1207 has a channel codec which, under the control of the CPU 1201, subjects a control signal to processing such as scrambling and time-division multiplexes data onto a prescribed frame, and has functions for executing processing in such a manner that a digital signal that has been put in frame form can be modulated and wireless transmitted, transmitting the processed signal to an antenna 1208, demodulating a signal wirelessly received from the antenna 1208 and processing the demodulated signal into a digital signal in the form of a frame. The antenna 1208 sends and receives radio signals. A line controller 1209 performs communication with a terminal connected to the public line network 1104 and controls network calls. A bus 1210 is an internal bus for transmitting various signals within the wired communication device 1101.

FIG. 13 is a block diagram showing the construction the wireless communication terminal 1102.

The wireless communication terminal 1102 includes a CPU 1301 which is the nucleus of the terminal 1102 and supervises control of the overall terminal inclusive of its components and wireless controller in accordance with programs stored in a ROM 1302. The latter stores the control program of the CPU 1301. A RAM 1303 stores various data for controlling the CPU 1301 and provides a working area for various arithmetic operations.

A call set-up message creating unit 1304 creates a call-set up message sent to the PHS wireless link. A wireless link controller 1305 controls the PHS wireless link.

A radio unit 1306 has a channel codec which, under the control of the CPU 1301, subjects a control signal to processing such as scrambling and time-division multiplexes data onto a prescribed frame, and has functions for executing processing in such a manner that a digital signal that has been put in frame form can be modulated and wireless transmitted, transmitting the processed signal to an antenna 1307, demodulating a signal wirelessly received from the antenna 1307 and processing the demodulated signal into a digital signal in the form of a frame. The antenna 1307 sends and receives radio signals. A voice data input/output unit 1308 enters voice data which flows into the wireless link and outputs voice data which arrives from the wireless link. An image data input/output unit 1309 enters image data which flows into the wireless link and outputs image data which arrives from the wireless link. A bus 1310 is an internal bus for transmitting various signals within the wireless communication terminal 1102.

FIG. 14 is a block diagram illustrating the construction of the ISDN communication terminal 1103.

The ISDN communication terminal 1103 includes a CPU 1401 which is the nucleus of the terminal 1103 and supervises control of the overall terminal inclusive of its components and wireless controller in accordance with programs stored in a ROM 1402. The latter stores the control program of the CPU 1401. A RAM 1403 stores various data for controlling the CPU 1401 and provides a working area for various arithmetic operations.

A data disassembler 1404 analyzes data in a case where data, which used two PHS channels, of the data received from the ISDN line 1104 is bundled and sent. A data assembler 1405 is used in a case where voice data and image data is bundled and sent in a data transmission scheme using two PHS channels.

A call set-up message analyzer 1406 analyzes a call set-up message sent from the ISDN line. A line controller 1407 performs communication with a terminal connected to the public line network 1104 and controls network calls. A voice data input/output unit 1408 enters voice data which flows into the ISDN line and outputs voice data which arrives from the ISDN line. An image data input/output unit 1409 enters image data which flows into the ISDN line and outputs image data which arrives from the ISDN line. A bus 1410 is an internal bus for transmitting various signals within the wireless communication system.

A wireless frame used in this embodiment will now be described.

FIGS. 15A-15C are explanatory view illustrating the structure of a wireless frame used in this system. The details of the data within the frame will now be described.

FIG. 15A illustrates temporal constitution of a wireless control data frame. Uplink in FIG. 15A indicates communication from the wireless communication terminal 1102 to the wired communication device 1101, and downlink indicates communication from the wired communication device 1101 to the wireless communication terminal 1102. An uplink logical control channel (referred to as "LCCH" below) sends data using an uplink slot once in 5 ms. A downlink LCCH sends data using a downlink slot in a downlink intermittent transmission period of (5*n)ms.

FIG. 15B illustrates the structure of an LCCH superframe. This frame, which is constructed by bundling downlink LCCHs, transmits various control data. Here BC represents BCCH, which transmits a message related to system control, P1 through P6 each represent PCH, which is transmits a message related to an incoming call, and SC represents SCCH, which transmits a message related to the wireless link.

FIG. 15C illustrates the structure of a communication slot frame. Here R1 through R4 represent slots in which the wired communication device 1101 receives data. These correspond to channels 1 through 4 (first through fourth channels), respectively. Further, T1 through T4 are slots, which have been allocated to respective ones of the channels, in which the wireless communication terminal 1102 receives data.

The details of the operation of this embodiment having the construction set forth above will now be described. In this system, frames are constructed and control is performed as described above in order that communication may be performed between the wired communication device 1101 and the wireless communication terminal 1102.

Processing for when a transmission is performed between the wireless communication terminal 1102 and ISDN communication terminal 1103 will be described as the specific operation of this system.

FIG. 16 is an explanatory view showing a data communication sequence according to this embodiment.

Shown in FIG. 16 are a link channel establishment request 1601, link channel allocation 1602, PHS set-up 1603, PHS call set-up acceptance 1604, a definition information request 1605', a definition information response 1606, a wireless management function request 1607, a wireless management function request response 1608, security key set-up 1609, a move management function request 1610, a move management function request response 1611, an authentication request 1612, authentication confirmation 1613, additional information 1614, a PHS call 1615, a PHS answer 1616 and PHS answer confirmation 1617, ISDN call set-up 1620, ISDN call set-up acceptance, ISDN call 1622, ISDN response 1623, ISDN response confirmation 1624, data communication 1630 on the first channel of the PHS, data communication 1631 on the second channel of the PHS, and ISDN data communication 1632.

Here 1601.about.1617 perform communication on the PHS wireless logical control channel, 1620.about.1623 perform communication on the D channel of the ISDN, 1630, 1631 perform communication on the PHS communication channel, and 1632 performs communication on the B channel of the ISDN.

FIG. 17 is a flowchart illustrating a connection operation according to this embodiment, FIG. 18 is a flowchart showing the data transmission operation of the wired communication device 1101 according to this embodiment, and FIG. 19 is a flowchart showing the data reception operation of the ISDN communication terminal 1103 according to this embodiment.

When the link channel establishment request 1601 arrives from the wireless communication terminal 1102 (S1701) in FIG. 17, the CPU 1201 of the wired communication device 1101 sends the link channel allocation 1602 back to the wireless communication terminal 1102 (S1702). Next, when the PHS set-up request 1603 arrives from the wireless communication terminal 1102 (S1703), the CPU 1201 of the wired communication device 1101 sends the PHS call set-up acceptance 1604 back to the wireless communication terminal 1102 (S1704).

If the same call set-up 1603 whose destination is the ISDN terminal is again received from the wireless communication terminal 1102 (S1705), the CPU 1201 of the wired c