Communication management technique for a radiotelephone system including microcells

• US 5,546,443 A
• Filed: 10/26/1992
• Issued: 08/13/1996
• Est. Priority Date: 10/26/1992
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Raith, Alex K.
• Primary Examiner(s): Bost, Dwayne D.
• Application Number:
  US07/966,461
• Time in Patent Office: 1,387 Days
• Field of Search: 379/59, 455/33.1, 455/33.2, 455/33.3, 455/33.4, 455/34.1, 455/34.2, 455/51.1, 455/51.2, 455/54.2, 455/56.1
• US Class Current: 455/450
• CPC Class Codes: H04W 16/32 Hierarchical cell structures
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

In a radiotelephone system, the control channel in all cells in an area can be simulcasted. A microcell base station may be provided with a receiver to listen on the umbrella cell control channel for messages, in addition to listening on its own control channel for control information and call accesses, to facilitate the appropriate assignment of a call to a cell. Also, a microcell can share a control channel with an umbrella cell provided interference between the control channels is not excessive. Further, microcells can share a common control channel independent of the overlying macrocell structure.

Claims

1. A method for establishing communications in a multi-layered radiotelephone system having a plurality of microcells and an umbrella cell and a mobile switching center, comprising the steps of:

receiving a call access request on a first control channel assigned to the umbrella cell, wherein the first control channel has at least one predetermined radio frequency;

receiving said call access request on a second control channel assigned to a microcell wherein said second control channel has the at least one predetermined radio frequency; and

assigning a call associated with said call access request to one of said microcell and said umbrella cell;

wherein each microcell has a respective additional control channel, at least two of said additional control channels having at least one common radio frequency, and control information is transmitted simultaneously on said additional control channels having the at least one common radio frequency.

2. A system for establishing communications in a multi-layered radiotelephone system having a plurality of microcells and an umbrella cell and a mobile switching center, said system comprising:

means for receiving a call access request on a first control channel assigned to an umbrella cell, wherein the first control channel has at least one predetermined radio frequency;

means for receiving said call access request on a second control channel assigned to a microcell wherein said second control channel has the at least one predetermined radio frequency; and

means, included in the mobile switching center, for assigning a call associated with said call access request to one of said microcell and said umbrella cell;

wherein each microcell has a respective additional control channel, at least two of said additional control channels having at least one common radio frequency, and control information is transmitted simultaneously on said additional control channels having the at least one common radio frequency.