Cordless telephone which intermittently monitors predetermined channels from all available channels

• US 5,237,603 A
• Filed: 10/22/1992
• Issued: 08/17/1993
• Est. Priority Date: 12/11/1989
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Tanaka, Yoshikazu, Yamagata, Masato
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): Bost, Dwayne D.
• Application Number:
  US07/965,044
• Time in Patent Office: 299 Days
• Field of Search: 379/58, 379/61-63, 455/34.1, 455/34.2, 455/38.3, 455/54.2, 455/127, 455/343
• US Class Current: 455/464
• CPC Class Codes: H04M 1/72511 Searching for available channels
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A cordless telephone having a base unit connected to a telephone line network, a handset unit operable for communicating with the base unit by way of radio waves, a device for establishing a standby mode in which the handset unit intermittently monitors at least one predetermined channel in a standby mode and for alternatively establishing a low power sleep mode, a device at the base unit for detecting the arrival of an incoming call from the telephone line network and for informing the remote handset unit of the arrival through the predetermined channel, a device for exchanging information between the base unit and the handset unit identifying respective available channels thereof and a device for storing information identifying at least one of the available channels which is the same for both the base unit and the remote handset unit, and which constitutes the at least one predetermined channel which is intermittently monitored by the handset unit in the standby mode.

Claims

1. A cordless telephone comprising:

a base unit connected to a telephone line network;

a handset unit operable for communicating with said base unit by way of a radio link;

means for establishing a standby mode in which said handset unit intermittently monitors a plurality of predetermined channels and for alternatively establishing a low power sleep mode;

means at said base unit for detecting the arrival of an incoming call from said telephone network and for informing said handset unit of said arrival through one of said plurality of predetermined channels,

means for exchanging via said radio link between said base unit and said handset unit information identifying respective available channels thereof;

means for storing information identifying a plurality of said available channels which are the same for both said base unit and said handset unit; and

means for selecting, from among said plurality of available channels, said plurality of predetermined channels which are to be intermittently monitored by said handset in said standby mode, said plurality of predetermined channels consisting of fewer channels than said plurality of available channels.

2. A cordless telephone as in claim 1, wherein said plurality of predetermined channels consists of two channels.

3. A cordless telephone as in claim 2, wherein said handset unit and said base unit each comprise means for monitoring ten channels.

4. A cordless telephone comprising:

a base unit connected to a telephone line network;

a handset unit operable for communicating with said base unit by way of a radio link;

power supply means for each of said base and handset units;

reset means connected between each of said base and handset units and the respective one of said power supply means for detecting initiation of operation of the respective power supply means;

means for establishing a standby mode in which said handset unit intermittently monitors a plurality of predetermined channels and for alternatively establishing a low power sleep mode;

means at said base unit for detecting the arrival of an incoming call from said telephone network and for informing said handset unit of said arrival through one of said plurality of predetermined channels,

means for exchanging via said radio link between said base unit and said handset unit information identifying respective available channels thereof when said reset means detects initiation of operation of said power supply means for said base unit or said handset unit, respectively;

means for storing information identifying a plurality of said available channels which are the same for both said base unit and said handset unit; and

means for selecting, from among said plurality of available channels, said plurality of predetermined channels which are to be intermittently monitored by said handset unit in said standby mode, said plurality of predetermined channels consisting of fewer channels than said plurality of available channels.

5. A cordless telephone comprising:

a base unit connected to a telephone line network;

a handset unit operable for communicating with said base unit by way of a radio link;

means for establishing a standby mode in which said handset unit intermittently monitors a plurality of predetermined channels and for alternatively establishing a low power sleep mode;

means at said base unit for detecting the arrival of an incoming call from said telephone network and for informing said handset unit of said arrival through one of said plurality of predetermined channels,

means for exchanging via said radio link between said base unit and said handset unit information identifying respective available channels thereof when a telephone conversation is complete;

means for storing information identifying a plurality of said available channels which are the same for both said base unit and said handset unit; and

means for selecting, from among said plurality of available channels, said plurality of predetermined channels which are to be intermittently monitored by said handset in said standby mode, said plurality of predetermined channels consisting of fewer channels than said plurality of available channels.