Title:
移動通信システム
Document Type and Number:
Japanese Patent JP4932419
Kind Code:
B2
Abstract:
A mobile communication system in which a finite number of reference signal sequences used for uplink channel estimation or the like are reused among multiple cells includes a determining unit configured to determine a frequency band used by user terminals to which a reference signal sequence with a predetermined sequence length is assigned in each of the cells within an interference area, wherein the frequency band is determined to be different from frequency bands used in the other cells. Alternatively, the mobile communication system includes a changing unit configured to autonomously change to another of the reference signal sequences which does not cause interference, upon detecting interference from another of the cells to which the same reference signal sequence is assigned; a determining unit configured to randomly determine a frequency band or a reference signal sequence used by user terminals to which one of the reference signal sequences with a predetermined sequence length is assigned in each of the cells within an interference area; or a shifting unit configured to shift transmission timings of radio subframes in each of the cells within an interference area.
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Inventors:
Yoshiaki Ofuji
Kenichi Higuchi
Mamoru Sawahashi
Kenichi Higuchi
Mamoru Sawahashi
Application Number:
JP2006272342A
Publication Date:
May 16, 2012
Filing Date:
October 03, 2006
Export Citation:
Assignee:
NTT DoCoMo, Inc.
International Classes:
H04J1/00; H04W16/02; H04W16/10; H04W16/12; H04W16/14; H04W24/00; H04W28/04; H04W36/06; H04W72/02; H04W72/04
Domestic Patent References:
| JP2002505820A |
Attorney, Agent or Firm:
Tadahiko Ito