Handoff control in an enterprise division multiple access wireless system

• US 6,901,061 B1
• Filed: 09/05/2000
• Issued: 05/31/2005
• Est. Priority Date: 09/05/2000
• Status: Expired due to Fees

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Joo, Ki Hyun, Hyun, Sang Kyoon, Rha, Peter S., Kang, Chol Su
• Primary Examiner(s): Phunkulh, Bob A.
• Application Number:
  US09/655,102
• Time in Patent Office: 1,729 Days
• Field of Search: 370/338, 370/328, 370/329, 370/331, 370/332, 370/333, 370/335, 370/342, 370/441, 455/422.1, 455/436, 455/437, 455/438, 455/439, 455/440, 455/441, 455/442, 455/443, 455/444
• US Class Current: 370/335
• CPC Class Codes: H04W 36/00837 Determination of triggering parameters for hand-off
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/38 by fixed network equipment
• CPC Class Codes: H04W 4/04 using association of physical positions and logical data in a dedicated environment, e.g. buildings or vehicles
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A wireless office communication system including a wireless internet base station (WIBS) encompassing a base station controller, a mobile switch controller and an ethernet interface module for coupling the WIBS to an existing internet protocol (IP) based network. A wireless office communication system can also be based on the conventional architecture comprising the BTS, BSC and MSC. The WIBS or BTS is attached to a number of antennas via different and identifiable delay elements for the purpose of determining the serving antennas of mobile communication units. A location determination logic enables the system to handle handoffs between a WIBS or BTS and the external public communication system in an optimum manner. Handling handoff requests in this manner prevents unnecessary ping-ponging of handoff and can also increase the percentage of successful handoff by frequency monitoring of the quality of the mobile communication units located in the handoff transition area, particularly to the public communication system.

Claims

1. An enterprise optimized hand-off control wireless code division multiple access, CDMA, communication system, comprising:

a local area network, LAN, having an ethernet communication back-bone;

a plurality of CDMA wireless base stations coupled to said ethernet communication back-bone;

a plurality of extended antenna units coupled to said CDMA wireless base stations;

a communication path coupled to said ethernet communication back-bone;

a signal distribution concentration unit coupled to said base stations;

a delay circuit unit coupled to said antenna units, the delay circuit unit including a plurality of delay elements for delaying signals transmitted via the communication path to external wireless communication devices within the enterprise wireless communication system.

2. The system of claim 1, wherein said delay circuit unit comprises a signal transmit distribution subsystem unit coupled to distribute communication signals received by the delay circuit unit within the enterprise wireless communication system to said extended antenna units.

3. The system of claim 1, wherein said delay circuit unit further comprises a signal receive concentration subsystem coupled to receive communication signals generated by communication devices within the enterprise wireless communication system, said signal receive concentration subsystem transmitting said communication signals.

4. The system of claim 2, wherein said signal transmit distribution subsystem comprises a plurality of signal transmit delay elements coupled to a signal dividing unit.

5. The system of claim 3, wherein said signal receive concentration subsystem comprises a plurality of signal receive delay elements coupled to a signal combining unit.

6. The system of claim 1, wherein said CDMA wireless base stations include a user location determination logic for determining a location of a mobile communication user within the enterprise communication system.

7. The system of claim 4, wherein said delay circuit unit further comprises delay signal strength detection logic for determining which delayed signal received by the delay circuit unit must be transmitted to a receiving target mobile communication device within the enterprise communication system.