Radio telephone system which utilizes an infrared signal communication link

• US 5,636,264 A
• Filed: 12/05/1995
• Issued: 06/03/1997
• Est. Priority Date: 08/18/1992
• Status: Expired due to Term

• Current Assignee: Nokia Mobile Phones UK Limited (Nokia Corporation)
• Original Assignee: Nokia Mobile Phones UK Limited (Nokia Corporation)
• Inventors: Hamalainen, Jari, Terho, Mikko, Sulavuori, Toni
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): Maung, Nay
• Application Number:
  US08/567,634
• Time in Patent Office: 546 Days
• Field of Search: 379/58, 379/56, 455/38.3, 455/127, 455/343
• US Class Current: 398/41
• CPC Class Codes: H04B 10/1143 Bidirectional transmission
• CPC Class Codes: H04B 10/116 Visible light communication
• CPC Class Codes: H04M 1/72412 using two-way short-range wireless interfaces
• CPC Class Codes: H04M 1/737 Characterised by transmission of electromagnetic waves other than radio waves, e.g. infrared waves
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

A radio telephone system comprising a transceiver unit and an external device, such as a handset, computer or telecopier, in wireless infrared signal communication with the transceiver unit. The information transmitted between the transceiver unit and the external device is transmitted as infrared digital pulses. The infrared pulses maybe transmitted in four digital time division multiplexed channels.

Claims

1. A radio telephone system comprising a transceiver unit and an external device in infrared signal communication with the transceiver unit via an infrared link, wherein:

the transceiver unit comprises;

a first transceiver means for bi-directionally communicating signals representing at least one of speech and data, and RF transceiver means for bi-directionally communicating with at least one RF channel and bi-directionally coupling electrical signals representing said at least one of speech and data between said RF channel and said first transceiver means;

the external device comprises;

a second transceiver means for bi-directionally communicating signals representing said at least one of speech and data;

and said system further comprising;

system clock means for producing a timing signal having regular time slots for timing the communication of said bi-directionally communicating signals;

means for bi-directionally communicating infrared signals in digital pulsed form, having at least one of a reduced bit rate and a reduced pulse width with respect to said regular time slots to lower average power consumption, over said infrared link between said transceiver unit and said external device, comprising;

optical transceiver means, optically coupled over said infrared link to one of said first and second transceiver means, for bi-directionally convering infrared signals in digital pulsed form to and from electrical signals representing one of speech and data, and coupling said electrical signals representing one of speech and data bi-directionally to the one of said first and second transceivers not optically coupled to said optical transceiver means.

2. A system as claimed in claim 1, wherein said optical transceiver means optically couples the infrared signals over said infrared link as wireless infrared signals.

3. A system as claimed in claim 1, wherein said optical transceiver means optically couples the infrared signals over said infrared link through an optical cable.

4. A system as claimed in claim 1, wherein said optical transceiver means is separate from and connected to the one of said first and second transceivers not coupled optically to said optical transceiver means via a cable.

5. A system as claimed in claim 1, wherein said infrared and electrical signals comprise signals representing both speech and data and the infrared signals are transmitted over the infrared link in four digital time division multiplexed channels, including one speech channel and one data channel in both directions.

6. A system as claimed in claim 5, further comprising:

means for controlling the external device and the transceiver unit to transmit and receive signals representing speech and data at a correct moment in the time division multiplexed digital channels to produce synchronism with said regular time slots, whereby speech and data signals are sent bi-directionally in a multiplexed manner by said optical transceiver means.

7. A system as claimed in claim 1, wherein the external device and the transceiver unit have means for encoding signals representing speech into digital form, said encoding means comprising a continuously variable delta (CVSD) modulator.

8. A method of transmitting information bi-directionally between an external device and a transceiver unit by means of an infrared signal over an infrared link, comprising the steps of:

producing electrical signals indicative of said information using an RF transceiver in said transceiver unit that bi-directionally communicates with at least one RF channel carrying said information;

producing a clocking signal having regular time slots for timing said bi-directional communication;

bi-directionally communicating infrared signals indicative of said information in digital pulsed form over said infrared link to and from said transceiver unit, by converting electrical signals to infrared digital signals having at least one of a reduced bit rate and a reduced pulse width with respect to the clocking signal time slots to lower average power consumption, and converting said infrared digital signals back to electrical signals, indicative of said information respectively from and to said RF transceiver using a first optical transceiver bi-directionally coupled to said RF transceiver in said transceiver unit;

bi-directionally communicating said infrared digital signals indicative of said information over said infrared link by coupling said first optical transceiver with a second optical transceiver disposed externally of said transceiver unit, and using said second optical transceiver to convert said infrared digital signals back to electrical signals, and electrical signals to said infrared digital signals, indicative of said information respectively from and to said first optical transceiver; and

bi-directionally coupling said second optical transceiver electrically to said external device.

9. A method as claimed in claim 8, wherein the infrared digital signals are transmitted over said infrared link as a wireless infrared signal.

10. A method as claimed in claim 8, wherein the infrared digital signals are transmitted over said infrared link through an optical cable.

11. A method as claimed in claim 8, wherein said information comprises at least one of speech and data.

12. A method as claimed in claim 8, wherein the infrared digital signals are transmitted over the infrared link in four time division multiplexed channels, including one speech channel and one data channel in both directions.

13. A method as claimed in claim 8, wherein the first optical transceiver and the second optical transceiver are provided with continuously variable delta (CVDS) modulators for encoding said electrical signals into digital form.

14. A communications system, comprising:

a first device having a first transceiver means for bi-directionally communicating signals representing information;

a second device comprising a second transceiver means for bi-directionally communicating signals representing said information, and an RF transceiver means for bi-directionally communicating signals representing said information between at least one RF channel and said second transceiver means;

system clock means for producing a timing signal having regular time slots for timing the communication of said bi-directionally communicating signals; and

optical transceiver means, capable of producing bi-directional digital infrared (IR) pulse signals, having at least one of a reduced bit rate and a reduced pulse width with respect to said regular time slots to lower average power consumption, in response to and indicative of said signals representing said information, for optically coupling said first device and said second device through pulsed IR communication with one of said first and second transceivers, to digitally communicate said signals representing said information, bi-directionally with lower average power consumption between said first and second devices.

15. A system as in claim 14 wherein said first device comprises at least one of a telephone handset, a computer, and a telecopier.

16. A system as in claim 14 wherein said second device comprises a cellular phone.

17. A system as in claim 14 wherein said optical transceiver means comprises a PCMCIA card.

18. A system as in claim 14 wherein said optical transceiver means is disposed in one of said first and second devices.

19. A system as in claim 14 wherein said optical transceiver means further comprises first electrical connector means for bi-directionally communicating electrical signals representing said information, and the other of said one of said first and second transceivers comprises second electrical connector means for bi-directionally communicating electrical signals representing said information with said first electrical connector means.

20. A system as in claim 14 wherein said information comprises speech and data and said optical transceiver means and said one of said first and second transceivers are coupled by bi-directional digital infrared (IR) pulse signals in four time division multiplexed communication channels comprising one channel for conducting electrical signals representing speech, and one channel for conducting electrical signals representing data, in both directions.