CELLULAR PHONE ADAPTOR

Abstract: A cellular phone adaptor (10) for compatible communication between a cellular phone (11, 12) and a cellular phone external device is disclosed. The cellular phone is either an analog cellular phone (11) having a transmitter and a receiver arranged to receive and transmit analog signals or a digital cellular phone (12) having a transmitter and a receiver arranged to receive and transmit digital signals. The adaptor (10) comprises an input connector (13) to which the cellular phone (11, 12) is connected, an output connector (14) which is connected to the external device and signal processing means to convert the transmitter analog signals or the transmitter digital signals from the analog or digital cellular phone (11, 12) connected at the input connector. The transmitter analog signals or transmitter digital signals are converted into a preset signal being provided to the output connector (14) and is compatible with the external device. The signal processing means is arranged to convert a signal received form the external device (14) into a preset analog signal or a preset digital signal compatible with the receivers of the analog or the digital cellular phone (11, 12) respectively. The preset analog signal or preset digital signal is selected from a number of preset signals corresponding to different signals associated with a number of different analog or digital cellular phones. Power supply means is connected to supply power to the analog or digital cellular phone (11, 12) connected to the adaptor (10) at the input connector (13) according to its particular power requirements.

Description: CELLULAR PHONE ADAPTOR The present invention relates to cellular phones and. in particular, to a cellular phone adaptor for a connection between a cellular phone and a cellular external device such as a hands free kit or some similar device. BACKGROUND TO THE INVENTION At present, external devices, such as hands free operation kits, for different makes or models of cellular phones are generally not compatible with other makes or models of cellular phones. This situation is due to the fact that the levels of analog signals and the formats of digital signals from the transmitters and to the receivers of the cellular phones are not standardised, differing in the range of makes or models of cellular phones. There have been proposals to overcome this problem by using cellular phone external devices which use an acoustic link between the cellular phone and its external device. Such proposals have the disadvantage that the link, based on "acoustic coupling" is very sensitive to acoustic "noise". The presence of acoustic noise prevents the use of many useful features associated with external devices, such as "on air" or "call in" when using hands free kits, as these features require electrical connection. It is believed that there is a need for a cellular phone adaptor for a connection between a cellular phone and a cellular external device such as a hands free kit or some similar device which is able to connect different makes or models of cellular phones to the external device. This would enable a cellular phone user to use his particular make or model of cellular phone in a non compatible hands free kit. Although the foregoing and the following description refers primarily to hands free kits for cellular phones, the present invention is not necessarily limited thereto. The present invention extends to other telecommunication apparatus and equipment and the like which allows compatibility to different non standard signals OBJECT OF THE INVENTION Therefore it is the object of the invention to provide a cellular phone adaptor for a connection between a cellular phone and a cellular external device which substantially overcomes or ameliorates the above mentioned problems. At the very least the object of the present invention is to provide an alternative to known cellular phone adaptors. DISCLOSURE OF THE INVENTION According to one aspect of the present invention there is provided a cellular phone adaptor for compatible communication between a cellular phone and a cellular phone external device, said cellular phone being either an analog cellular phone having a transmitter and a receiver arranged to receive and transmit analog signals or a digital cellular phone having a transmitter and a receiver arranged to receive and transmit digital signals, said adaptor comprising an input connector to which the cellular phone is connected and an output connector which is connected to said external device, signal processing means to convert said transmitter analog signals or said transmitter digital signals from said analog or said digital cellular phone connected at said input connector, said transmitter analog signals or said transmitter digital being converted into a preset signal being provided to said output connector and being compatible with said external device, said signal processing means being arranged to convert a signal received from said external device into a preset analog signal or a preset digital signal compatible with the receivers of the analog or the digital cellular phone respectively, said preset analog signal or said preset digital signal being selected from a number of preset signals corresponding to different signals associated with a number of different analog or digital cellular phones, and power supply means being connected to supply power to said analog or digital cellular phone connected to said adaptor at the input connector according to its particular power requirements. BRIEF DESCRIPTION OF THE DRAWINGS One embodiment of the present invention will now be described with reference to the drawings in which: Fig. 1 is a schematic block diagram of a cellular phone adaptor of a preferred embodiment; and Fig. 2 is a schematic block diagram of the cellular phone adaptor of Fig. 1 being shown connected to a modified car radio receiver. BEST MODE OF CARRYING OUT THE INVENTION A cellular phone adaptor 10 of the preferred embodiment of the present invention is for use with a cellular external device such as a so-called hands free kit (not illustrated) which can be used in motor vehicles or the like. The cellular phone adaptor 10 is connected to the external device such that any cellular phone can be connected thereto for use therewith. This is the case whether the cellular phone is operated on an analog network or a digital network. For ease of description, the cellular phones are referred to herein as an analog cellular phone 11 and a digital cellular phone 12 as illustrated in Fig. 1. The adaptor 10 includes an input connector 13 to which the analog cellular phone 1 1 or the digital cellular phone 12 can be connected thereto, and an output connector 14 which is connectable to the cellular phone external device. The actual connecting pins and cradles (not illustrated) are suitable for use with a variety of makes and styles of cellular phone handsets and external devices therefor. The adaptor 10 also includes as its internal components a first analog processor 15, a second analog processor 16. a digital to analog converter (DAC) 17, an analog to digital converter (ADC) 18, a power supply/battery charger 19. control circuitry 21 and a control circuitry selector 22. If the cellular phone is the analog cellular phone 1 1, it is connected to the adaptor 10 via the input connector 13 as shown in Fig. 1. Its transmitter (TX) is connected through to the first analog processor 15 which is connected through to the output connector 14 which in turn is connected to the external device. An analog signal is received by the first analog processor 15 from the analog cellular phone 11. The first analog processor 15 is in its basic form an amplifier/attenuator device of analog signals and depending on the analog signals received at its input from the analog cellular phone 11 it produces modified analog signals at preset values at its output which are then provided to the external device. The receiver (RX) of the analog cellular phone 11 is connected through to the second analog processor 16 which in turn is connected to the output connector 14. The analog signals received by the second analog processor 16 from the external device via the output connector 14 are processed by the second analog processor 16 which is also in its basic form an amplifier/attenuator device of analog signals. The analog signals received at the input of the second analog processor 16 are modified such that the analog signals provided at its output to the receiver RX of the analog cellular phone 11 are at preset values such as required by the particular make or model of the analog cellular phone 1 1. Both the first and second analog processors 15 and 16 are controlled by the control circuitry 21 by means of control signal received therefrom. The control circuitry selector 22 is used to select the parameters which are to be used by the control circuitry 21 to adjust the operation of the first and second analog processors 15 and 16 to produce the analog signals for the matching operation of the adaptor 10. The control circuitry 21 preferably comprises a microprocessor with the control circuitry selector 22 preferably being a non volatile memory which can be programmed with the data of the requirements of different makes and models of analog and digital cellular phones. The selector 22 therefore arranges for the control circuitry 21 to control the operation of the first and second analog processors 15 and 16 according to the make and model of the analog cellular phone 11 being used with the adaptor 10 and therefore the external device such as the hands free kit. The selector 22 must be changed according to the make and model of the analog phone 1 1. Each different make and model of phones can have data installed into the control circuitry 21 and the selector 22 in order that they are able to be used with the adaptor 10 of the preferred embodiment of the present invention. Other arrangements such as EPROMs. and programable switches such as a switch bank where selection is made by changing the combination of on/off settings on the switch bank can be used to select the operation of the control circuitry 21 and hence the first and second analog processors 15 and 16. When the analog cellular phone 1 1 is in use, the call/on air signal generated by the analog cellular phone 1 1 can vary in its logical state (low/high) from make or model of cellular phone. Therefore as shown in Fig. 1, the call/on output (c/o) of the analog cellular phone 1 1 is connected to the control circuitry 21 whereby the signal received is compared with a logic state programmed or otherwise installed into the control circuitry 21 as selected by the selector 22. If a call/on air signal is detected by the control circuitry 21 a call/on signal is provided to the output connector 14 from the control circuitry 21. This call/on signal provided to the external device is always the same logical state as chosen for the operation of the adaptor 10. This chosen logical state is therefore required for the operation of the adaptor 10 with the particular analog cellular phone 1 1 when a call in signal is received by the external device. If the cellular phone is the digital cellular phone 12, it is connected to the adaptor 10 via the input connector 13 as shown in Fig. 1. The transmitter TX of the digital cellular phone 12 is connected through to the digital to analog converter 17 which in turn is connected to the first analog processor 15 which is connected to the output connector 14 as described above. The digital signal received by the DAC 17 is converted to an analog signal which is then modified by the first analog processor as described above. The digital format of the DAC 17 is controlled by the control circuitry 21 by means of a control signal received therefrom based on the data installed therein and as selected by the selector 22. The digital format of the DAC 17 is matched to the digital signal received by the digital cellular phone 12. The receiver RX of the digital cellular phone 12 is connected through to the analog to digital converter 18 which in turn is connected to the second analog processor 16 which is connected to the output connector 14 as described above. The analog signals received by the external device are processed by the second analog processor 16 as described above and are then provided to the ADC 18 to be converted to digital signals compatible with the receiver RX of the digital cellular phone 12. The operation of the ADC 18 and the second analog processor 16 are controlled by the control circuitry 21 as selected by the selector 22 as described above such that the digitally encoded signal is compatible with the digital cellular phone 12. The adaptor 10 is also used to supply power to the cellular phone whether it is the analog cellular phone 11 or the digital cellular phone 12. The power supply/battery charger 19 is connected between the input connector 13 and the output connector 14 and is controlled by the control circuitry 21 as selected by the selector 22 in accordance with the previously described methods. The power supply/battery charger 19 provides power to the cellular phones 11 and 12 according to their requirements as determined by the control circuitry 21 and the selector 22. The adaptor 10 and analog or digital cellular phone 11 or 12 are shown in an example of their use whereby a modified car radio 30 can have the adaptor 10 and hence analog or digital cellular phone 1 1 or 12 connected thereto for use as an external device such as a hands free kit. The modified car radio 30 can be manufactured and installed in motor vehicles so that the motor vehicle can have a built in cellular phone hands free operational device which is programmable to operate with a cellular phone of any number of different makes or models that the user may wish to use therein. The modified car radio 30 with the adaptor 10 and analog or digital cellular phone 11 or 12 connected thereto is shown in Fig. 2 in a block diagram. The modified car radio 30 includes additional componentry 31 shown in the box with the broken lines. This additional componentry 31 includes a level detector 32, a microphone amplifier 33 and a relay driver 34. An additional microphone 35 is also provided while an on/off switch 36 of the car radio 30 is used. The modified car radio 30 also includes a relay 37, a tuner 38, an intermediate frequency amplifier 39, a pair of low frequency amplifiers 40 and 41 with corresponding speakers 42 and 43. A signal from the transmitter TX of the analog or digital cellular phone 11 or 12 is processed by the adaptor 10 as previously described and is then provided to the level detector 32 and thence to the relay 37. The level detector 32 is used to control the gain of the microphone amplifier 33 and minimises acoustic feedback. The relay 37 connects to one of the LF amps 40 and therefore to the speaker 42. The microphone 35 is connected to the input of the microphone amplifier 33 which amplifies an analog signal corresponding to the voice received by the microphone 35 and provides it to the adaptor 10 and the analog or digital cellular phone 11 or 12 for transmission therefrom. A call/on signal output from the analog or digital cellular phone 1 1 or 12 is connected to the adaptor 10 and thence to the relay driver 34 which is used to operate the relay 7 as required. The received signal from the receiver of the analog or digital cellular phone 1 1 or 12 is then provided to the LF amp 40 and speaker 42 so that the user can hear from the modified car radio 30. Once the relay driver 34 drives the relay 37 power is always supplied via the V cc terminal through the contacts numbered 3 and 4. This means that the LF amp 40 will always operate when the relay 37 is driven even if the radio is switched off. Naturally if power is removed from the modified car radio 30 it will not be operational. The contacts numbered 5 and 6 of the relay 37 shouts down the preamplifiers (not illustrated) of the LF amps 40 and 41 so that only the signal received from the analog or digital cellular phone 1 1 or 12 connected to the adaptor 10 is amplified and heard through the speaker 42. A filter (not illustrated) is preferably used on the signal from contact 2 of the relay 37 to suppress frequencies greater than 3.4 kHz and to amplify the signal to a power level of about 1 watt in order to minimise acoustic feedback and echoing. The foregoing describes only some embodiments of the present invention, and modifications obvious to those skilled in the art can be made thereto without departing from the scope of the present invention. For example, a serial port connector with a serial port communicator with a modem function can be incorporated into the adaptor circuitry and therefore external devices having serial communicator (to RS232), such as computers, test instruments, etc can be connected through the adaptor to the cellular phone.

Claims: CLAIMS 1. A cellular phone adaptor for compatible communication between a cellular phone and a cellular phone external device, said cellular phone being either an analog cellular phone having a transmitter and a receiver arranged to receive and transmit analog signals or a digital cellular phone having a transmitter and a receiver arranged to receive and transmit digital signals, said adaptor comprising an input connector to which the cellular phone is connected and an output connector which is connected to said external device, signal processing means to convert said transmitter analog signals or said transmitter digital signals from said analog or said digital cellular phone connected at said input connector, said transmitter analog signals or said transmitter digital being converted into a preset signal being provided to said output connector and being compatible with said external device, said signal processing means being arranged to convert a signal received from said external device into a preset analog signal or a preset digital signal compatible with the receivers of the analog or the digital cellular phone respectively, said preset analog signal or said preset digital signal being selected from a number of preset signals corresponding to different signals associated with a number of different analog or digital cellular phones, and power supply means being connected to supply power to said analog or digital cellular phone connected to said adaptor at the input connector according to its particular power requirements. 2. The cellular phone adaptor according to claim 1 , wherein said signal processing means comprises at least one analog processor to process said transmitter analog signals from said analog cellular phone and said signals received from said external device. 3. The cellular phone adaptor according to claim 2, wherein said signal processing means further comprises a digital to analog converter means to convert said transmitter digital signals from said digital cellular phone prior to processing by said at least one analog processor and an analog to digital converter means to convert said processed signal from said at least one analog processor received from said external device. 4. The cellular phone adaptor according to any one of claims 1-3. wherein signal processing means is controlled by control circuitry and a selector means which is selected according to the type and make of the cellular phone. 5. The cellular phone adaptor according to claim 4, wherein said control circuitry comprises a microprocessor. 6. The cellular phone adaptor according to claim 4, wherein said selector means comprises programmable non-volatile memory. 7. The cellular phone adaptor according to claim 4, wherein said selector means comprises a switch bank and selection is made by changing the combination of on/off settings on the switch bank. 8. The cellular phone adaptor according to any one of the preceding claims, wherein said external device includes a serial port communicator with modem functions.

Inventors: CHEKLIN ALEX, CHEKLIN, ALEX
Applicants: CHEKLIN ALEX, MUM WORLD ENTERPRISES PTY LTD, CHEKLIN, ALEX, MUM WORLD ENTERPRISES PTY. LTD.
Application year: 1997
Main classification: H04B7
IPC codes: H04B7, H04W88