HK1037836B - Transmission of data packets over cdma type cellular telephone - Google Patents

Description

Data packet transmission via CDMA cellular telephone

Technical Field

The present invention relates to the transmission of PPP data packets from networking application software running on a host computer to a network such as the internet, and in particular to the transmission of such data packets via a CDMA (code division multiple access) type cellular telephone.

Background

It is commonplace for a user to connect his/her computer to the internet. Computer users can make such connections using a variety of popular serial networking application software packages and send PPP (point-to-point protocol) data packets to accessory devices such as modems. (modems may also be integrated with computers). Many of these popular serial networking applications wait until a signal (referred to as a "connect" signal) is received indicating that the accessory device is dialing the requested telephone number and has completed a particular "handshaking" protocol with the corresponding remote modem before sending the PPP data packet. Other networking applications send PPP data packets after the user-defined command AT + CRM equals 1. Once the AT + CRM command is set, it is the setting for all networking applications residing on the computer, and if the user wants to switch from the asynchronous mode of communication (where AT + CRM must be set to 0) to the packet data mode (where AT + CRM must be set to 1), the user must clear the AT + CRM command AT each switch of modes.

To establish a PPP data packet call, CDMA type cellular telephones do not dial a telephone number and complete the usual "handshaking" protocol. The networking application will not receive the connect signal and will not begin sending PPP data packets unless some additional action occurs, such as setting AT + CRM command to 1. There is therefore a need for a simple and convenient procedure to bring up networking applications that typically require a "connect" signal to send PPP data packets when connecting with the internet via a CDMA type device, such as a CDMA type cellular telephone. Such a procedure should not require the user to clear the AT + CRM command each time the user changes modes.

Disclosure of Invention

To cause the networking application software to send PPP data packets, a data-capable CDMA subscriber device (e.g., a cellular telephone) monitors the telephone dial-string commands sent by the networking application and compares them to a set of reserved telephone numbers. When the subscriber device detects/receives a typical "AT" dial-string command, the subscriber device checks the telephone number contained within the dial-string and compares it to the reserved telephone number.

If the telephone number contained within the dial-string is not one of the reserved numbers, the CDMA device will construct a normal asynchronous data call and send the call over the system. The IWF (integrated work function) responds by returning an expected "connect" signal to the networked application. Upon receiving the expected "connect" signal, the networking application will then transmit asynchronously in the normal manner.

If the telephone number contained within the dial-string matches one of the set of reserved numbers, the CDMA device does not construct a CDMA call in an asynchronous format (i.e., asynchronous service option 0 x 0004, 0 x 0005, 0 x 1004, 0 x 1005, 0 x 12, or 0 x 13). Instead, it constructs a data packet call (i.e., packet service option 0 x 0007, 0 x 00015, or 0 x 1007) and simply sends a return "connect" signal to the networking application. This can mistake networking applications to believe that the CDMA device is connected to the remote modem at approximately the same time. The networking application then sends PPP packets via the CDMA subscriber device as needed.

Other features and advantages of the present invention will be further understood from the following description of the invention taken in conjunction with the accompanying drawings.

Brief Description of Drawings

Figure 1 shows a typical system for connecting a computer to the internet using a modem and public telephone system.

Fig. 2 shows a system using a CDMA cellular telephone and base station for connecting a computer to the internet using a CDMA asynchronous data service.

Fig. 3 is a system utilizing a CDMA cellular telephone and base station configured in accordance with the present invention for connecting a computer to the internet utilizing a CDMA packet data service.

Fig. 4 is a detailed illustration of computer resident networking software and CDMA subscriber device (e.g., cellular telephone) features configured in accordance with the invention.

Best mode for carrying out the invention

Communication between the desktop or laptop computer 10 and what is generally known as the internet 22 may be conveniently accomplished by means of a system such as that shown in fig. 1. The computer 10 is connected to a remote modem 16 of an internet service provider 18 via a public telephone line 12 and a public telephone system 14. An internet service provider connects computer 10 to the internet 22 using any acceptable communications path 20. Requests to access the internet (or other "network") are typically initiated by computer users via the networking application software package 24. The computer user provides the dialed telephone number to the networking application software to access the desired internet service provider. The user commands the networking application software 24 to access the internet. Software 24 then transmits the telephone number of the internet service provider's modem 16 to a modem 26 connected to computer 10. Modem 26 may be integral with the computer or may be a separate device connected to the computer by suitable means. Modem 26 then sends the appropriate signal, i.e., a dial-string command containing the telephone number of the destination modem 16, to modem 16 over public telephone system 14 via telephone line 12. Modems 26 and 16 then engage in the usual "handshaking" protocol to establish a connection with internet service provider 18. Once the protocol is completed and the connection is confirmed, the modem 26 returns a connection signal to the application software 24. Only after receiving the connection signal does the networking application software 24 begin sending PPP data packets over the system to the final destination within the internet (or other network).

In today's fast paced world, computer users may "run" with portable laptop computers and may not have access to the telephone line 12. In this case, a system such as that shown in FIG. 2 may be used to connect the computer 10 to the Internet 22. The laptop computer is provided with a hard-wired direct connection 28 to a cellular telephone 30 that is capable of CDMA asynchronous data services. Although computer 10 may include an integrated modem 26, the modem is not connected to a cellular telephone. Instead, the cellular telephone 30 is connected directly to the data port of the computer 10 through the direct connection 28. The cellular telephone 30 utilizes an antenna 32 to transmit data in the form of electromagnetic waves via an antenna 34 to a connected base station system 36 comprising a base station 38 and an IWF 40. The base station system is connected to a modem 26' similar to the modem 26 of fig. 1. Modem 26' is connected to physical telephone line 12 (as is modem 26). As shown in fig. 2, the remaining paths to the internet 22 are the same as those shown in fig. 1. The operation of the system shown in fig. 2 is substantially the same as the system shown in fig. 1. In fig. 2, the cellular telephone 30, base station system 36 and modem 26' only access the physical telephone line 12. In other words, they correspond to physical line connections to the telephone line 12. Modem 26 'and modem 16 participate in a specific "handshake" protocol, and when a connection is established, modem 26' sends a connection signal to networking application software 24 via the system, prompting the start of sending PPP data packets. No data packet is sent until a connection signal is received.

The system architecture shown in fig. 2 is typical of an asynchronous call. The time required for the local modem 26' to dial the remote modem 16 is substantially the same. For example, the total time taken to set up a telephone call and complete a "handshake" protocol typically exceeds 25 seconds. Air time on a cellular telephone is expensive and a long delay time is a major annoyance to many users.

Fig. 3 shows a communication system comprising a computer connected to the internet via a cellular telephone capable of implementing CDMA packet data services. In order for the system to work, the networking application software must send PPP packets to the cell phone. Some commonly used networking application software packages send PPP packets only after instructing the adjunct modem 26 to dial the remote modem and receiving a notification signal (e.g., a connect signal) back that the remote modem and the adjunct modem have completed a "handshake" protocol. A CDMA phone that wishes to use packet data services will not use a modem and therefore will not receive such a notification signal. But the current CDMA telephony standard allows a user to initiate PPP data packet transmission by setting the command AT + CRM to 1. But this is not a simple and convenient matter for many users. The present invention may utilize this commonly used networking application by causing the cellular telephone to return a connect signal after receiving a preselected "reserved" telephone number, thereby causing the networking application to send PPP data packets. The reserved set of telephone numbers may be pre-set by the telephone manufacturer or by the user. The telephone number requested by the networking application software may also be conveniently defined by the user through the user interface, and a different telephone number may be defined for each resident networking application software package.

It will be apparent that "telephone numbers" are used herein as examples, but that "telephone numbers" may be any desired combination of symbols and/or digits, and thus are also referred to herein as "data items" in various instances throughout this specification.

Before a user can command the networking application software 24 of the computer 10 to access the internet, the user generally must first provide the software 24 with the appropriate dialing telephone number. For this purpose, the telephone number is entered into the networking application via the user interface. Subsequently, when the user instructs access to the internet, the networking application software will dial the designated telephone number. When a user instructs a networking application to connect, the networking application typically issues an ATD or ATDT command to the connected device (e.g., modem or cell phone). The software 24 typically then waits to receive a connection signal (in accordance with the resulting code format such as "connect", "connect 19200", etc. and/or the rising edge of the carrier sense pin). But since the cellular telephone is not a modem and does not dial a telephone number and perform any modem "handshaking" protocol, the return connection signal will not be received unless the user takes the required additional action to properly set the AT + CRM command (which is generally inconvenient). The networking application will not start sending PP data packets. The present invention allows a user to easily and conveniently instruct the system to configure for a packet data call.

The best mode of carrying out the invention is illustrated with the aid of fig. 4. The user first programs the cellular telephone 30 by entering one or more "reserved" telephone numbers into a memory register within the cellular telephone, such as a look-up table 54. The connection signal is also stored in a memory register 56 within the cellular telephone. The "reserved" telephone number may not be the actual telephone number but may be a series of required numbers or symbols. For example, the reserved telephone number may be #777 or # 999. The user also provides the networking application software with a data item equivalent to the dialed telephone number by entering the data into a register 50 (or 50' or 50 ") specified by the various networking application software packages.

When the user instructs the networking application software 24 to connect to the internet, the software 24 retrieves the specified telephone number (or data) from the register 50 and constructs a dial-string command containing the specified telephone number, and provides the dial-string command to the cellular telephone 30 via the direct connection 28. The cellular telephone 30 then completes the connection with the base station system 36, extracts the telephone number from the dial-string command, and compares the extracted telephone number with the reserved telephone number stored in the look-up table 54. If a match is detected, the cellular telephone 30 immediately retrieves the connection signal from the register 56 and returns to the networking application software 24 via the direct connection 28. The networking application software 24 may thus assume that the connection with the remote modem is completed and the PPP data packets are beginning to be sent to the cellular telephone 30 at approximately the same time.

If the user stores the unreserved number in the register 50 of the networking application software, the cellular telephone determines that it does not match any of the reserved numbers stored in the look-up table 54 and establishes an asynchronous data call. And then until the IWF of the system sends a connection signal to the networking application software.

Improved systems and methods for transmitting PPP data packets via CDMA type devices, such as CDMA type cellular telephones, are thus described. It will be appreciated that those skilled in the art, on reading the description of the invention, may devise various modifications of the invention without departing from the spirit and scope of the invention, which is limited only by the appended claims.

Claims (11)

1. A method of operating a CDMA type subscriber device to send data packets from a networking application resident on a computer to a network, comprising the steps of:

a) providing a first data item to said networking application storing the data item as a called telephone number to effectuate access to the network;

b) storing at least one second data item in a memory register of the CDMA type subscriber device;

c) comparing the first data item with the at least one second data item;

d) if the first data item matches the at least one second data item, then constructing a packet data call and providing a signal to the networking application software indicating that the subscriber device is ready to receive data; and (c) and (d).

e) Constructing an asynchronous call if the first data item is inconsistent with the at least one second data item.

2. The method of claim 1, wherein the at least one second data item comprises a plurality of data items stored in a storage register comprising a lookup table.

3. The method of claim 1, further characterized by the steps of:

b)1) receiving a dial-string command from the networking application, the dial-string command containing the first data item.

4. The method of claim 1, wherein the signal comprises a connection signal.

5. The method of claim 1 wherein said signal comprises a signal that raises a carrier connection pin.

6. A CDMA-type subscriber device configured to be capable of sending data packets from a computer to a network via serial networking application software resident on said computer, comprising:

a) a first storage register for storing at least one reserved telephone number;

b) a second storage register for storing a signal indicating that the subscriber device is ready to receive the packet data;

c) a processor for comparing the at least one reserved telephone number with a number received from the networking application and sending the signal to the networking application if the comparison indicates a match; and

d) the subscriber device initiating a packet data call upon detecting the match.

7. The device of claim 6 wherein said CDMA type device comprises a CDMA capable cellular telephone.

8. The apparatus of claim 6, wherein said signal comprises a connection signal.

9. The apparatus of claim 6 wherein said signal comprises a signal that raises a carrier connection pin.

10. The apparatus of claim 6 wherein said first memory register contains a look-up table and said at least one reserved telephone number comprises a plurality of reserved telephone numbers.

11. The apparatus of claim 6, wherein the apparatus further initiates the packet data call according to a packet service option selected from options 0 x 0007, 0 x 00015 and 0 x 1007.