Connection method of digital cordless telephone apparatus

• US 5,737,325 A
• Filed: 12/07/1995
• Issued: 04/07/1998
• Est. Priority Date: 12/09/1994
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Fukuda, Kunio
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): PHILLIPS, MATTHEW
• Application Number:
  US08/568,647
• Time in Patent Office: 852 Days
• Field of Search: 370/336, 370/337, 370/345, 370/347, 370/311, 370/277-280, 370/442, 370/458, 370/459, 370/501, 379/61, 455/426, 455/434, 455/450, 455/464, 455/509, 455/518, 455/519
• US Class Current: 370/337
• CPC Class Codes: H04M 1/72505 Radio link set-up procedures
• CPC Class Codes: H04M 1/72513 On hold, intercom or transfer communication modes

Abstract

A connection method of a digital cordless telephone apparatus allows communication between a first calling side portable unit and a second called side portable unit of the plurality of portable units. The first portable unit transmits an access request signal for requesting a call to the second portable unit. A base unit receives an access request signal and determines whether or not there are any transmission slots and reception slots available for connecting the first portable unit to the second portable unit via the base unit. If there are the available transmission slots and reception slots, then the base unit uses usable slots to allow a call between the first portable unit and the second portable unit. If there are no available transmission slots and reception slots, then the base unit transmits a control signal including busy information. The first portable unit receives the control signal and transmits to the second portable unit a direct access request signal for requesting a call to the second portable unit. The second portable unit receives the direct access request signal, thereby communicating with the first portable unit.

Claims

1. A connection method of a digital cordless telephone apparatus which includes a base unit and a plurality of portable units, in which one channel is divided into frames in view of time, each frame being formed of a plurality of transmission slots and a plurality of reception slots, in which digital data is transmitted and received during respective periods of said transmission slots and said reception slots, and in which by using said plurality of transmission slots and reception slots in each of said frames, said base unit can communicate with said plurality of portable units and provide communication between one portable unit and another portable unit of said plurality of portable units via said base unit, said connection method being used to establish a connection for communication between a first calling side portable unit and a second called side portable unit of said plurality of portable units, comprising the steps of:

at said first portable unit, transmitting an access request signal for requesting a call to said second portable unit;

at said base unit receiving the access request signal and determining whether there are any transmission slots and reception slots available for connecting said first portable unit to said second portable unit via said base unit;

if there are any available transmission slots and reception slots, allowing a call between said first portable unit and said second portable unit by using the available slots;

if there are no available transmission slots and reception slots, transmitting a control signal including busy information;

at said first portable unit;

determining whether it is possible to receive the control signal from said base unit;

if said first portable unit can receive the control signal receiving the control signal and transmitting to said second portable unit a direct access request signal for requesting a call to said second portable unit; and

at said second portable unit, receiving the direct access request signal, thereby communicating with said first portable unit.

2. A connection method of a digital cordless telephone apparatus according to claim 1, wherein portable units other than said first portable unit among said plurality of portable units are respectively switched to a standby state for reception of said direct access request signal when receiving said control signal including said busy information.

3. A connection method of a digital cordless telephone apparatus which includes a base unit and a plurality of portable units, in which one channel is divided into frames in view of time, each frame being formed of a plurality of transmission slots and a plurality of reception slots, in which digital data is transmitted and received during respective periods of said transmission slots and said reception slots, and in which by using said plurality of transmission slots and reception slots in each one of said frames, said base unit can communicate with said plurality of portable units and provide communication between one portable unit and another portable unit of said plurality of portable units via said base unit, said connection method being used to establish a connection for communication between a first calling side portable unit and a second called side portable unit of said plurality of portable units, comprising the steps of:

at said first portable unit, determining whether it is possible to receive a control signal from said base unit;

if said first portable unit cannot receive said control signal, transmitting a direct access request signal to said second portable unit; and

at said second portable unit, receiving the direct access request signal, thereby communicating with said first portable unit.

4. A connection method of a digital cordless telephone apparatus according to claim 3, wherein when said first portable unit of said plurality of portable units determines that it cannot receive said control signal, portable units other than said first portable unit are respectively switched to a standby state for reception of said control signal and said direct access request signal.