JP2004500746A - Optical data interface for wireless telephones - Google Patents

Abstract

A system for connecting a wireless telephone (20) to an external circuit (22). The system includes a first optical data interface adapter (42) connected to the wireless telephone. The system also includes a second optical data interface adapter (24). An optical fiber cable (28) connects the first optical data interface adapter (42) to the second optical data interface adapter (24). In a particular embodiment, the wireless telephone is a cellular telephone (20), wherein the computer (22) is connected to a second optical data interface adapter (24). The first and second optical data interface adapters (42, 24) include an optical transmitter (56, 54) and a photodetector (58, 52).

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to wireless communication systems. In particular, the present invention relates to systems and methods for transmitting data between wireless telephones and other electronic devices.
[0002]
[Prior art]
Many mobile phones are controlled using a computer and can receive interrogation signals. In many cases, the computer can set phone information or retrieve the current status, state or level. Therefore, many measurements can be taken by linking special telephone test software running on a computer under test to a cellular telephone.
[0003]
Conventional metal conductor cables, such as standard serial computer cables, are commonly used to connect a cellular telephone to a computer. However, when a cable is connected between a telephone and a computer, the cable often reduces the radiation performance of the cellular telephone. Generally, when a data cable is connected to a cellular telephone, the data cable is connected to an internal telephone ground, which disturbs the antenna radiation pattern of the telephone and significantly reduces its performance. Further performance degradation results from radio frequency (RF) interference emitted from the cable.
[0004]
In short, existing wired data cables often reduce the radiated performance of cellular and personal communication system (PCS) telephones. As a result, expensive acoustic equipment is often required to take telephone FM measurements.
[0005]
Infrared data links are an alternative method of providing a data link to a wireless telephone. Generally, infrared energy is transmitted without a cable between an infrared sensor on a telephone and an infrared sensor on a computer attachment. However, data link performance is degraded by bright sunlight. This is problematic in an outdoor telephone test environment. In addition, infrared data links are easily blocked due to objects located between the telephone and the associated external computer. Further, external electromagnetic signals from other infrared devices, such as television remote controls, can cause significant interference, which degrades the performance of the infrared data link.
[0006]
[Problems to be solved by the invention]
Accordingly, there is a need in the art for an effective system and method for transmitting data between a wireless telephone and external circuitry, such as a computer, with minimal degradation of the telephone. There is a further need for a cost-effective system that facilitates accurate cellular / PCS phone measurements in environments characterized by electromagnetic noise.
[0007]
[Means for Solving the Problems]
This technical need is addressed by the system for connecting a wireless telephone of the present invention to external circuitry. In an exemplary embodiment, the inventive system is adapted for use with a cellular telephone and an external computer. The inventive system is used with a wireless telephone and includes a first optical data interface adapter designed to be connected to the wireless telephone and a second optical data interface adapter. An optical fiber cable connects the first optical data interface adapter to the second optical data interface adapter.
[0008]
In certain embodiments, the wireless telephone is a cellular telephone and the computer is connected to a second optical data interface adapter. The first and second optical data interface adapters include an optical transmitter and a photo detector.
[0009]
In an alternative embodiment, the invention is implemented as a system for making a wireless call from a computer through a wireless telephone. The system includes an external computer and an optical data link between the telephone and the computer. Software running on the computer controls the wireless telephone over the optical data link and allows the computer to make calls through the wireless telephone.
[0010]
Alternatively, the present invention is a system for taking measurements on a wireless telephone, including a computer optically connected to the wireless telephone. Measurement software running on the computer controls the flow of information, so that information about the wireless telephone is obtained by the computer.
[0011]
The novel design of the present invention is facilitated by the use of fiber optic cables to optically transmit and receive data to and from a computer. The optical nature of transmission reduces or eliminates interference between data transmitted over fiber optic cables and electromagnetic energy transmitted and received by wireless telephones.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Although the present invention has been described herein with reference to illustrative embodiments for particular applications, it should be understood that the invention is not limited thereto. Those skilled in the art, having access to the teachings provided herein, will recognize additional modifications, applications, and embodiments within its scope and within the additional areas in which the present invention has significant utility.
[0013]
The following review of the operation of conventional cellular telephone data interface adapters and associated cables is intended to facilitate an understanding of the present invention.
[0014]
FIG. 1 is a diagram of a cellular telephone 10 connected to a typical data interface adapter 12 and associated cables 14 for connecting to an external computer (not shown). The antenna current flows along cable 14 and is likely to interfere with data transmission along cable 14 and alter the radiation pattern of the telephone antenna system. Further, noise generated by the digital bit stream in cable 14 may interfere with the wireless transmission and reception of cellular communication signals through cellular telephone 10.
[0015]
FIG. 2 is a diagram of an arrangement constructed in accordance with the teachings of the present invention. A cellular telephone 20 and a computer 22 are attached to a telephone fiber optic data interface adapter 24 and a computer fiber optic data interface adapter 26, respectively. The two adapters are interconnected with a fiber optic cable 28. The antenna current is diverted at the telephone fiber optic data interface adapter 24 and does not interfere with data transmission across the fiber optic cable 28. The noise generated by the digital signals in computer 22 is diverted at computer fiber optic data interface adapter 26, which suppresses or prevents the noise from interfering with the transmission and reception of cellular telephone wireless signals.
[0016]
Fiber optic data interface adapters 24 and 26 may include photodetectors and transmitters known in the art (not shown). These devices are commercially available. For example, the transmitter can be purchased from Siemens as a SFH750V transmitter, and the photodetector can be purchased as a Siemens SFH551 / 1-V-1 photodetector. Optical transmitters facilitate converting electrical signals to optical signals for transmission over fiber optic cable 28. In a preferred embodiment, the fiber optic cable is a Mitsubishi EHV 4002 fiber optic cable.
[0017]
Unlike previous approaches that provide a data interface to a cellular telephone, the unique design of the present invention does not disrupt the antenna radiation pattern of the cellular telephone and causes interference between the computer electronics and the transmission and reception of the cellular telephone. Without facilitating data transmission between the cellular telephone 20 and the computer 22. As a result, the present invention is ideal for applications involving the use of cellular telephone 20 as a modem for computer 22.
[0018]
In this exemplary embodiment, the software running on computer 22 controls cellular telephone 20, so that the cellular telephone operates as a computer modem. Additional software, described further below, is provided for execution by computer 22 and takes data from telephone 20 and measures the performance of telephone 20. Having access to this teaching, software, including additional software, as described in further detail below, is readily developed and implemented by those skilled in the art.
[0019]
FIG. 3 shows the cellular telephone 20 of FIG. 1 attached to the cellular telephone wireless data interface adapter 40 and the computer wireless data interface adapter 42 of the present invention for generating a wireless data interface 44 between the cellular telephone 20 and the computer 22 and 1 is a diagram of a computer 22. The antenna current deviates at the cellular telephone wireless data interface adapter 40 and the noise generated by the digital signals within the computer 22 deviates at the computer wireless data interface adapter 42. Wireless interface 44 replaces fiber optic cable 28 of FIG. In this exemplary embodiment, the wireless interface is implemented by optical transmission, such as through a Siemens laser transmitter, or by infrared transmission through a Hewlett-Packard IRDA infrared transceiver.
[0020]
FIG. 4 is a more detailed block diagram of the arrangement of FIG. 2, showing various electrical components within the telephone fiber optic data interface adapter 24 and the computer wireless data interface adapter 42. The arrangement includes, from left to right, a computer 22, a telephone fiber optic data interface adapter 24, a fiber optic cable, a computer wireless data interface adapter 42, and a cellular telephone 20.
[0021]
From left to right, the computer fiber optic data interface adapter 24 includes an RS-232 for a transistor-transistor logic (TTL) driver 50, a first photodetector 52 and a first optical transmitter 54 in parallel therewith. It is included. Fiber optic cables 28 both connect first photodetector 52 to second transmitter 56 and first transmitter 54 to second photodetector 58 in optical data interface adapter 42. . Second transmitter 56 and photodetector 58 are connected to cellular telephone 20 through a standard connection system.
[0022]
In this particular embodiment, fiber optic cable 28 is a duplex plastic fiber optic cable. The interface between the TTL driver 50 and the first photodetector 52 and the interface between the TTL driver 50 and the first transmitter 54 are standard interfaces known in the art. The TTL driver 50 is made with Analog Devices part number ADM202EARW, dual RS-232 driver / receiver. Photodetectors 52 and 58 are Siemens SFH551 / 1-V-1 plastic optical fiber integrated photodetectors. Transmitters 54 and 56 are Siemens SFH750V plastic optical fiber transmitter diodes. Duplex fiber optic cable 28 is a Mitsubishi EHV 4002 1000 micron 2 plastic fiber optic cable.
[0023]
In operation, TTL data to be directed from the computer 22 to the cellular telephone 20 is sent to a TTL driver 50, which is a standard serial bus driver. As is known in the art, the TTL driver 50 can support two transmission paths and two reception paths. The TTL data is formatted for RS-232 serial transmission and sent to the first transmitter 54. The first transmitter 54 converts the electrical serial data into serial optical data, which is transmitted to the second optical detector 58 through the optical fiber cable 28, where the serial optical data is transmitted to the second optical detector 58. The data is converted back into electrical signals, which are then sent to the cellular telephone 20. Cellular telephone 20 then processes the electrical serial data through circuitry such as a baseband processor (not shown) on a baseband chip (not shown).
[0024]
Similarly, the TTL serial data to be sent from the cellular telephone 20 to the computer 22 is directed to a second optical transmitter 56, which converts the TTL serial data into optical TTL serial data, It is sent to the first photodetector 52 through the fiber cable 28, where it is detected and converted into electrical TTL serial data. The electrical TTL serial data is sent to the TTL driver 50, where it is converted to the RS-232 format. The TTL data is then sent to computer 22 for further processing.
[0025]
The TTL driver 50 may be replaced with another type of driver without departing from the scope of the present invention. Also, the location of the TTL driver 50 may be switched to the cellular telephone optical data interface adapter 42 without departing from the scope of the present invention. Other additional drivers may be included in interface adapters 24 and 42 and / or in computer 22 or cellular telephone 20 without departing from the scope of the present invention.
[0026]
FIG. 5 is a flow diagram of the software 70 of the present invention that facilitates communication (see FIGS. 2 and 3) between a wireless telephone and a computer through the data interface of the present invention (see FIGS. 2, 3 and 4). Referring to FIG. 2, software 70 includes routines residing in computer 22 and routines residing on a wireless telephone computer (not shown) in wireless telephone 20.
[0027]
In a first power check step 72, software running on computer 22 checks whether wireless telephone 20 is turned on. If the wireless telephone 20 has not been turned on, the software 70 ends. If the wireless telephone 20 is turned on, control is transferred to a command waiting step 74.
[0028]
In command wait step 74, software executing on computer 22 waits for a request for data and / or other user commands from a user of computer 22. Commands and / or requests may be entered through conventional input devices such as a keyboard or mouse or a combination thereof. If no command is entered during the predetermined time in the command waiting step 74, the wireless telephone 20 is turned off, or the software 70 ends when the user issues an end command. Otherwise, if the software running on computer 22 receives a user request for data and / or other commands other than an end command, control is transferred to communication step 76.
[0029]
In a communication step 76, software running on computer 22 initiates communication with wireless telephone 20 (by software running on the wireless telephone computer) and is received by software running on computer 22 in a command waiting step 74. Send appropriate commands and / or requests to wireless telephone 20 based on the received commands and / or requests. Once the wireless telephone 20 receives the command and / or request through the optical data interface 28, control is transferred to processing step 78. In processing step 78, a software routine running on wireless telephone 20 processes the request and / or command and then returns an appropriate response to software running on computer 22. The details of the software routines that execute on wireless telephone 20 to enable communication to be established and to process requests and / or commands can be developed by those skilled in the art without undue experimentation. Once a software routine running on wireless telephone 20 processes the request and / or command, control is returned to wait for command step 74. This forms a loop that includes steps 74, 76 and 78, which ends when the telephone is turned off, the user issues an end command, or the software routine times out.
[0030]
Accordingly, the present invention has been described herein with reference to a particular embodiment for a particular application. Those skilled in the art having access to this teaching will recognize additional modifications, applications and embodiments within the scope of the present invention.
[0031]
It is therefore intended that the claims cover any and all such applications, modifications and embodiments within the scope of the invention.
[Brief description of the drawings]
FIG.
FIG. 1 is an illustration of a cellular telephone connected to a typical data interface adapter and associated cables for connecting to an external computer.
FIG. 2
FIG. 2 is a diagram of an arrangement constructed in accordance with the teachings of the present invention.
FIG. 3
FIG. 3 is an illustration of the arrangement of FIG. 2 attached to a wireless data interface adapter according to the teachings of the present invention that creates a wireless data interface between a cellular telephone and a computer.
FIG. 4
FIG. 4 is a more detailed block diagram of the arrangement of FIG. 2 showing various electrical components.
FIG. 5
FIG. 5 is a software flow diagram of the present invention that facilitates communication between a wireless telephone and a computer through the data interfaces of FIGS.

Claims (11)

In a system for connecting a wireless telephone to an external circuit,
A first optical data interface adapter adapted for use with the wireless telephone and connected to the wireless telephone;
A second optical data interface adapter connected to the circuit;
A fiber optic cable connecting the first optical data interface adapter to the second optical data interface adapter. The system of claim 1, wherein said wireless telephone is a cellular telephone. The system according to claim 1, wherein the electric circuit is a computer. The system of claim 1, wherein said first and second optical data interface adapters include an optical transmitter and a photodetector. In a system for transmitting information between a computer and a wireless telephone,
An optical data interface link between the computer and the wireless telephone;
Software running on the computer and controlling the flow of information between the computer and the wireless telephone. In a system for making wireless calls from computers,
A wireless phone,
A computer outside the wireless telephone,
An optical data link between the wireless telephone and the computer;
Software controlling the wireless telephone over the optical data link and executing on the computer so that the computer can make calls through the wireless telephone. The system of claim 6, wherein the wireless telephone includes a telephone data interface adapter for the wireless telephone, and the computer includes a computer data interface adapter for the computer. 7. The system of claim 6, wherein said optical data link comprises a fiber optic cable connecting said wireless telephone data interface adapter to said computer data interface adapter. The system of claim 7, wherein the telephone data interface adapter and the computer data interface adapter each include a transmitter and a photodetector. In a system for measuring the performance of a wireless telephone,
A computer optically connected to the wireless telephone for transmitting information between the wireless telephone and a computer;
Controlling the information so that frequency modulation information about the wireless telephone is obtained by the computer, and executing measurement software on the computer. In a method of facilitating communication between a computer and a wireless telephone,
Waiting for a user request and / or command to be input to the computer by a user;
Initiating communication between the computer and the wireless telephone through an optical interface between the computer and the wireless telephone in response to receiving a user request and / or command by the computer;
Processing the request and / or command through software running on the wireless telephone in response to receiving the user request and / or command received from the computer through the optical interface.

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