METHOD AND SYSTEM FOR MOBILE COMMUNICATIONS

• US 20090197646A1
• Filed: 04/09/2009
• Published: 08/06/2009
• Est. Priority Date: 04/24/1997
• Status: Active Grant

• Current Assignee: NTT Mobile Communications Network Inc. (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Mobile Communications Network Inc. (Nippon Telegraph and Telephone Corporation)
• Inventors: Watanabe, Yasuyuki, Sato, Takaaki, Hata, Masafumi, Tamura, Motoshi, Uchiyama, Nobuhide, Igarashi, Daisuke, Uchikoshi, Akihiro, Okamoto, Akiko, Ishikawa, Nobutaka, Hagiwara, Junichiro, Miki, Mutsumaru, Hamajima, Takuya, Yunoki, Kazufumi, Yasuda, Yoshiyuki, Kusunose, Kenya, Yamagata, Katsuhiko
• Granted Patent: US 8,185,158 B2
• Time in Patent Office: Days
• US Class Current: 455/561
• CPC Class Codes: H04B 7/022 Site diversity; Macro-diversity using two or more spaced independent antennas H04B7/04
• CPC Class Codes: H04W 12/03 Protecting confidentiality, e.g. by encryption
• CPC Class Codes: H04W 12/06 Authentication
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 36/302 due to low signal strength
• CPC Class Codes: H04W 52/04 TPC
• CPC Class Codes: H04W 52/12 Outer and inner loops
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 88/12 Access point controller devices

Abstract

When a network pages the temporary user mobile identifier of a mobile station, the mobile station sends a response to the network. Next, the network checks the authenticity of the user using a ciphering key, corresponding to the temporary user mobile identifier and a random number. If the temporary user mobile identifier is authenticated, a normal incoming call acceptance procedure is executed. If the mobile station is authenticated although the temporary user mobile identifier is wrong, the network reassigns a new temporary user mobile identifier to the mobile station and stops the current communication. In communication, the network and the mobile station mutually notify encipherment-onset time and negotiate about encipherment manner with each other. In addition, diversity handover is commenced upon a call attempt. Furthermore, if a branch replacement is necessary, the current branch is replaced by new branches capable of executing the diversity handover. Additionally, when a new call occurs to or from the mobile station capable of treating a plurality of calls simultaneously, the mobile station uses the same branch structure and the same communication frequency band for all of calls. Additionally, when a new call occurs to or from the mobile station capable of treating a plurality of calls simultaneously, a branch structure and a communication frequency band, which can continue all of the calls, are selected and used. Therefore, the mobile communications system is suitable for transmission of various sorts of data in accordance with the development of multimedia.

Claims

1. A base station comprising

a transmitter configured to transmit broadcast information indicating at least an uplink interference level via a perch channel.

2. The base station according to claim 1, wherein the broadcast information indicates a perch channel transmission power level and the uplink interference level via a perch channel.

3. The base station according to claim 2, wherein the perch channel transmission power level is calibrated on the basis of the path losses at cables within the base station.