Hybrid telephony communication system

• US 4,775,996 A
• Filed: 09/30/1987
• Issued: 10/04/1988
• Est. Priority Date: 09/30/1987
• Status: Expired due to Term

• Current Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Original Assignee: Northern Telecom Limited (Nortel Networks Corporation)
• Inventors: Koohgoli, Mahshad, Bannister, Cecil H., Emerson, Victor F.
• Primary Examiner(s): NOT, DEFINED
• Application Number:
  US07/102,944
• Time in Patent Office: 370 Days
• Field of Search: 379/61, 379/62, 379/63, 379/56, 455/601, 455/603, 455/607
• US Class Current: 379/56.3
• CPC Class Codes: H04M 1/737 Characterised by transmission of electromagnetic waves other than radio waves, e.g. infrared waves

Abstract

A wireless telephony system comprising a base station and at least one portable device. The base station employs a ratio frequency (RF) receiver and an optical transmitter. The portable device employs an optical receiver and an RF transmitter.

Claims

1. A telephony communications system for providing wireless communications between a base station and a portable device, said telephony communications system comprising:

a base station for receiving information from a telephony switching office, said base station having an optical transmitter for transmitting to said portable device information received from said switching office, and a radio frequency receiver for receiving information from said portable device and relaying said information from said portable device to said switching office;

at least one portable device for receiving information from said base station in the optical frequency spectrum and for sending information to said base station in the radio frequency spectrum.

2. The telecommunications system of claim 1 wherein said optical frequency spectrum is in the infra-red range.

3. A base station for use in a wireless telephony communications system that provides wireless communications between said base station and a portable device said base station comprising:

interface means for connecting said base station to a telephony switching office;

an optical transmitting means for transmitting information received from said switching office; and

a radio frequency receiver means for receiving information in the radio frequency spectrum emanating from said portable device.

4. The base station of claim 3 wherein said optical transmitting means operates in the infra-red frequency spectrum.

5. A portable device for use in a wireless telephony communications system that provides wireless communications between a base station and said portable device, said portable device comprising:

a radio frequency transmitter means for transmitting information from said portable device to said base station; and

an optical receiver means for receiving information in the optical frequency spectrum emanating from said base station.

6. The portable device of claim 5 wherein said optical receiver means operates in the infra-red frequency spectrum.