| 摘要 |
PURPOSE: A method for cooperative operation between a macro cell and a Femto cell base station is provided to minimize interference between Femto cell base stations, by optimizing transmission power of adjacent Femto cell base stations on the ground of a received power report of a Femto cell user terminal. CONSTITUTION: A macro cell user terminal receiving service from a macro cell base station judges interference from a fixed Femto cell base station among adjacent Femto cell base stations (S14). It is judged whether signal-to-interference plus noise ratio (SINR) of the macro cell user terminal decreased less than a first threshold, by the interference from the fixed Femto cell base station (S15). When the SINR of the macro cell user terminal decreases less than the first threshold, transmission power of the fixed Femto cell base station is reduced so that the SINR of the macro cell user terminal exceeds the first threshold (S16). [Reference numerals] (AA) Start; (BB,EE,FF,HH,JJ,LL,NN) No; (CC,DD,EE,GG,II,KK,MM,OO) Yes; (PP) Return; (S10) Femto control operation mode; (S11) Macro cell user affected by a Femto cell is detected?; (S12) Predetermined moving speed is excess?; (S13) Power control operation mode; (S14) Macro cell user SINR reduction?; (S15) Reduced below a first threshold value?; (S16) Reduced below a second threshold value?; (S17) Hand-off with a femto cell is possible?; (S18) Femto cell transmission capacity expectancy value > Macro cell transmission capacity expectancy value; (S19) Handoff operation mode; (S20) Frequency evasion operation mode |
