Base Station Apparatus,Wireless Communication System,And Wireless Transmission Method

Abstract

Allocation of transmission power is carried out adaptively without affecting adjacent cells. There are comprised a reception part ( 132 ) that receives information from a mobile station apparatus, a transmission power determination part ( 125 ) that determines transmission power when transmitting a wireless signal to a mobile station apparatus based on the received information, an acquisition part ( 120 ) that acquires information about communication environment in each time channel or each frequency channel from the received information, a scheduling part ( 120 ) that identifies a time channel or frequency channel the relationship of which between transmission power and communication environment satisfies the condition for allocation and allocates transmission data and transmission power for transmission to a mobile station apparatus to a communication slot in the time channel or frequency channel, and a transmission part ( 130, 131 ) that transmits a wireless signal using the communication slot to which the transmission data and the determined transmission power have been allocated.

1 . A base station apparatus that uses a plurality of slots and performs wireless communication with a mobile station apparatus in a cell, wherein 
 said base station apparatus:    receives information from said mobile station apparatus;    determines transmission power to be allocated to a group of said slots as well as determining transmission power when transmitting a wireless signal to said mobile station apparatus based on said received information;    determines a group of slots or part of a group of slots for transmitting transmission data based on the transmission power when transmitting the wireless signal to said mobile station apparatus and the transmission power allocated to said group of slots; and    transmits the wireless signal to said mobile station apparatus using said determined group of slots or said determined part of said group of slots.    
   
   
       2 . The base station apparatus according to  claim 1 , which has a plurality of time channels and performs wireless communication with a mobile station apparatus in a cell using said time channel, wherein 
 said base station apparatus:    receives information from said mobile station apparatus;    determines transmission power to be allocated to said time channel as well as determining transmission power when transmitting a wireless signal to said mobile station apparatus based on said received information;    determines a time channel or part of time channel for transmitting transmission data based on the transmission power when transmitting the wireless signal to said mobile station apparatus and the transmission power allocated to said time channel; and    transmits the wireless signal to said mobile station apparatus using said determined time channel or said determined part of time channel.    
   
   
       3 . The base station apparatus according to  claim 1 , which has a plurality of frequency channels and performs wireless communication with a mobile station apparatus in a cell using said frequency channel, wherein 
 said base station apparatus:    receives information from said mobile station apparatus;    determines transmission power to be allocated to said frequency channel as well as determining transmission power when transmitting a wireless signal to said mobile station apparatus based on said received information;    determines a frequency channel or part of frequency channel for transmitting transmission data based on the transmission power when transmitting the wireless signal to said mobile station apparatus and the transmission power allocated to said frequency channel; and    transmits the wireless signal to said mobile station apparatus using a frequency band corresponding to said determined frequency channel or said determined part of frequency channel.    
   
   
       4 . The base station apparatus according to either  claim 2  or  claim 3 , wherein 
 the condition for determining the allocation of time channel or part of time channel, or frequency channel or part of frequency channel for transmitting said transmission data is any one of the following conditions that:    the interference power at said mobile station apparatus is the smallest;    the magnitude of transmission power and the magnitude of interference power at said mobile station are associated in advance in a relationship of inverse proportion and interference power corresponding to said determined transmission power is possessed; and    the ratio between reception signal power and interference power at said mobile station apparatus is the maximum.    
   
   
       5 . The base station apparatus according to  claim 4 , wherein 
 when determining the allocation of time channel or part of time channel, or frequency channel or part of frequency channel for transmitting said transmission data, said base station apparatus:    divides the mobile station apparatus in said cell into a plurality of groups based on the information received from said mobile station apparatus; and    allocates slots for transmitting transmission data to the same time channel or the same frequency channel for a mobile station apparatus in said same group.    
   
   
       6 . The base station apparatus according to claim  45 , wherein 
 when determining the allocation of time channel or part of time channel, or frequency channel or part of frequency channel for transmitting said transmission data, said base station apparatus:    identifies said group to which the transmission power for transmitting a wireless signal to any one of the mobile station apparatus in said cell belongs; and    allocates, when there exists a vacant time channel or a vacant frequency channel in all of the individual time channels or the individual frequency channels or in the part thereof to which transmission power corresponding to a group with transmission power larger than that of said identified group has been allocated, a slot for transmitting transmission data to said mobile station apparatus to the vacant time channel or the vacant frequency channel.    
   
   
       7 . The base station apparatus according to  claim 5 , wherein 
 when determining the allocation of time channel or part of time channel, or frequency channel or part of frequency channel for transmitting said transmission data, said base station apparatus:    determines said group to which the transmission power for transmitting a wireless signal to any one of the mobile station apparatus in said cell belongs; and    allocates, when transmission data is not allocated to the time channel or the frequency channel allocated to said identified group and when there exists a vacant time channel or a vacant frequency channel in all of the time channels or the frequency channels or in the part thereof to which transmission power corresponding to a group with transmission power smaller than that of said identified group has been allocated, a slot for transmitting transmission data to said mobile station apparatus to the vacant time channel or the vacant frequency channel.    
   
   
       8 . The base station apparatus according to  claim 5 , wherein 
 said base station apparatus changes, after allocating a slot for transmitting said transmission data, the transmission power of said allocated slot based on said received information.    
   
   
       9 . The base station apparatus according to  claim 7 , wherein 
 said base station apparatus changes the modulation scheme when allocating transmission data to be transmitted to said mobile station apparatus and said transmission power to said vacant time channel or each vacant frequency channel.    
   
   
       10 . The base station apparatus according to either  claim 2  or  claim 3 , wherein 
 said base station apparatus updates said allocated transmission power at intervals of a certain period of time when determining the allocation of time channel or part of time channel, or frequency channel or part of frequency channel for transmitting said transmission data.    
   
   
       11 . The base station apparatus according to either  claim 2  or  claim 3 , wherein 
 said base station apparatus updates said allocated transmission power when determining the allocation of time channel or part of time channel, or frequency channel or part of frequency channel for transmitting said transmission data, and if there exists a mobile station apparatus that newly makes a request for connection in the cell and if any one of the mobile station apparatus moves, or if the situation of propagation path changes in any one of the mobile station apparatus.    
   
   
       12 . The base station apparatus according to  claim 10 , wherein 
 said base station apparatus allocates transmission power so that, when updating said transmission power, the difference between the transmission power immediately before the update and the transmission power to be allocated at the time of update is equal to or less than a fixed value.    
   
   
       13 . The base station apparatus according to either  claim 2  or  claim 3 , wherein 
 said base station apparatus allocates, when determining the allocation of time channel or part of time channel, or frequency channel or part of frequency channel for transmitting said transmission data:    transmission power with which a wireless signal can reach the entire range in the cell to at least one of said time channels or frequency channels; and    transmission power the influence of which on the adjacent cells can be ignored to at least one of said time channels or frequency channels.    
   
   
       14 . The base station apparatus according to  claim 13 , wherein 
 said base station apparatus:    acquires a level of interference received from the adjacent cells based on information received from said mobile station apparatus; and    determines said time channel or part thereof, or said frequency channel or part thereof to which the transmission power with which the wireless signal can reach the entire range in the cell is allocated in accordance with said measured interference level in order to transmit data other than said control data.    
   
   
       15 . The base station apparatus according to  claim 13 , wherein 
 said base station apparatus:    measures the number of adjacent cells based on the information received from said mobile station apparatus; and    determines, when determining the allocation of time channel, frequency channel, or communication slot for transmitting said transmission data, a number L of said time channels or said part thereof, or said frequency channels or said part thereof to which transmission power with which the wireless signal can reach the entire range in the cell is allocated in accordance with said measured interference level in order to transmit data other than said control data as such one that holds        L ≦(total number of time channels, frequency channels, or communication slots)/{(number of adjacent cells)+1}.    
   
   
       16 . The base station apparatus according to  claim 13 , wherein 
 said base station apparatus allocates, when determining the allocation of time channel or part of time channel, or frequency channel or part of frequency channel for transmitting said transmission data and if, on one hand, there exists a mobile station apparatus required to transmit a wireless signal with transmission power with which the wireless signal can reach the entire range in the cell and if, on the other hand, there exists no data to be transmitted to said mobile station apparatus, dummy data to be transmitted to said mobile station apparatus and the transmission power with which the wireless signal can reach the entire range in the cell to said time channel or said part thereof, or said frequency channel or said part thereof.    
   
   
       17 . The base station apparatus according to  claim 5 , wherein 
 said base station apparatus adds a hysteresis characteristic to the condition for the change of groups when the group to which the transmission power allocated to said mobile station apparatus belongs is changed due to the information received from said mobile station apparatus.    
   
   
       18 . A wireless communication system configured by: 
 the base station apparatus according to either  claim 2  or  claim 3;  and    at least one mobile station apparatus.    
   
   
       19 . A mobile station apparatus that is applied to the wireless communication system according to  claim 18 .  
   
   
       20 . A wireless communication method of a base station apparatus having a plurality of time channels and transmitting a wireless signal to a mobile station apparatus using said time channel, said method comprising at least: 
 a step for receiving information from said mobile station apparatus;    a step for determining transmission power when transmitting a wireless signal to said mobile station apparatus based on said received information;    a step for acquiring information about communication environment in each time channel from said received information;    a step for determining the allocation of time channel or part of time channel and transmission power for transmission to said mobile station apparatus based on said determined transmission power and said information about communication environment; and    a step for transmitting a wireless signal to said mobile station apparatus using the time channel or the part of time channel to which said transmission data and said determined transmission power have been allocated.    
   
   
       21 . A wireless communication method of a base station apparatus having a plurality of frequency channels and transmitting a wireless signal to a mobile station apparatus in a cell using said frequency channel, said method comprising at least: 
 a step for receiving information from said mobile station apparatus;    a step for determining transmission power when transmitting a wireless signal to said mobile station apparatus based on said received information;    a step for acquiring information about communication environment in each frequency channel from said received information;    a step for determining the allocation of frequency channel or part of frequency channel and transmission power for transmitting transmission data to said mobile station apparatus based on said determined transmission power and said information about communication environment; and    a step for transmitting a wireless signal to said mobile station apparatus using the frequency channel or the part of frequency channel to which said transmission data and said determined transmission power have been allocated.