Interference avoidance radio communications system

• US 6,741,837 B1
• Filed: 07/30/1999
• Issued: 05/25/2004
• Est. Priority Date: 05/20/1998
• Status: Expired due to Term

• 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: Hata, Masafumi, Onoe, Seizo, Ishii, Minami, Ishikawa, Yoshihiro, Nakano, Etsuhiro
• Primary Examiner(s): Chin, Vivian
• Assistant Examiner(s): CRAVER, CHARLES R
• Application Number:
  US09/364,938
• Time in Patent Office: 1,761 Days
• Field of Search: 455/422, 455/423, 455/424, 455/448, 455/13.4, 455/500, 455/501, 455/63, 455/67.1, 455/67.3, 455/1, 455/62, 455/456, 455/457, 455/92, 455/117, 455/440, 370/252, 375/144, 375/148, 375/224, 375/225, 375/226, 375/227, 375/285, 375/346, 375/348
• US Class Current: 455/67.11
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336
• CPC Class Codes: H04B 17/354 Adjacent channel leakage power
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 36/06 Reselecting a communication resource in the serving access point
• CPC Class Codes: H04W 52/0238 where the received signal is an unwanted signal, e.g. interference or idle signal
• CPC Class Codes: H04W 52/242 taking into account path loss
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 76/30 Connection release
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A base station 422 of a second system performs communication using a frequency adjacent to a frequency employed by communication between a base station 412 and a mobile station 414 of a first system. When the mobile station 414 is close to the base station 422, the communication of the base station 422 undergoes interference by the leakage power of the mobile station 414. To avoid the interference, the transmission is halted of the mobile station 414 of the first system, which provides the interference by the leakage power.

Claims

1. A mobile station in a radio communications system which includes at least one base station and at least one mobile station, the radio communications system being one of a plurality of the radio communications systems existing in one geographical area, each of which uses different frequencies, in which the mobile station, when in a communication mode, is associated with one of the radio communications systems, and cannot change that association during the communication mode, said mobile station comprising:

means for measuring a received signal level of a received signal at a frequency adjacent to its own assigned frequency by switching a frequency during a period in which no reception is required in a standby mode and in the communication mode; and

means for halting its transmission when the received signal level exceeds an acceptable level.