Methods and apparatus for broadcasting loading information corresponding to neighboring base stations

Abstract

Methods and apparatus are described where loading information regarding loading conditions at a neighboring base station is received at a first base station and then communicated, e.g., broadcast, by the first base station to mobiles within the cell in which the first base station is located. Since the neighbor base station's loading information is being communicated to a mobile currently connected to the first base station via a reliable communications channel of the first base station, the mobile can be expected to be able to reliably recover loading factor information corresponding to not only the first base station but to the neighboring base station. By utilizing such loading factor information, the mobile can generate an improved uplink interference report. The first base station receives such interference reports from wireless terminals in its cell, facilitating efficient resource allocation and interference control.

What is claimed is: 
     
         1 . A method of operating a first base station in a multiple access wireless communications system including a plurality of base stations, each of said plurality of base stations including at least one base station attachment point, the method comprising:
 receiving second base station loading factor information indicative of loading of a second base station attachment point corresponding to a second base station; and   broadcasting at least some of said received second base station loading factor information, said broadcasting being dependent on the level of loading of the base stations.   
     
     
         2 . The method of  claim 1 ,
 wherein said second base station is physically adjacent said first base station; and   wherein receiving second base station loading factor information includes receiving said second base station loading factor information over a backhaul link between said first and second base stations.   
     
     
         3 . The method of  claim 1 ,
 wherein said second base station is physically adjacent said first base station; and   wherein receiving second base station loading factor information includes receiving said second base station loading factor information from a mobile communications device which received said second base station loading factor information over a wireless communications link with said second base station.   
     
     
         4 . The method of  claim 1 , further comprising:
 determining a first uplink loading factor indicative of uplink loading for a first base station attachment point, said first base station attachment point corresponding to the first base station; and   transmitting, using a downlink broadcast communications channel, said first uplink loading factor in addition to said at least some second base station loading factor information, wherein said at least some second base station loading factor information includes a second uplink loading factor corresponding to said second base station attachment point.   
     
     
         5 . The method of  claim 4 , further comprising:
 receiving from a first wireless terminal a first uplink interference report;   receiving from a second wireless terminal a second uplink interference report;   determining uplink resource allocation as a function of said received first and second uplink interference reports.   
     
     
         6 . The method of  claim 5 , wherein said first and second uplink interference reports are a function of said transmitted first and second uplink loading factors. 
     
     
         7 . The method of  claim 6 , further comprising:
 prior to receiving the first uplink interference report, broadcasting a first broadcast signal; and   wherein said first uplink interference report is a function of a received power level measured by the first wireless terminal of said first broadcast signal, the first uplink loading factor, a received power level measurement by the first wireless terminal of a second broadcast signal from the second base station, and the second uplink loading factor.   
     
     
         8 . The method of  claim 7 , wherein said first broadcast signal from the first base station is one of a beacon and a pilot channel signal, and wherein said second broadcast signal from the second base station is one of a beacon and a pilot channel signal. 
     
     
         9 . The method of  claim 5 , wherein determining uplink resource allocation as a function of said received first and second uplink interference reports includes scheduling traffic channel segments. 
     
     
         10 . The method of  claim 5 , wherein determining uplink resource allocation as a function of said received first and second uplink interference reports includes initiating a handoff of the first wireless terminal from said first attachment point to said second attachment point. 
     
     
         11 . The method of  claim 5 , further comprising:
 receiving, via a backhaul link, a third uplink loading factor indicative of uplink loading for a third base station attachment point, said third base station attachment point corresponding to a third base station, said third base station being adjacent said base station; and   transmitting using a downlink broadcast communications channel said third uplink loading factor, wherein said first and second uplink interference reports have been determined as a function of said transmitted first, second, and third uplink loading factors.   
     
     
         12 . The method of  claim 5 , further comprising
 receiving, via a backhaul network, a third uplink loading factor indicative of uplink loading for a third base station attachment point, said third base station attachment point corresponding to said second base station, said second and third base station attachment points corresponding to different sectors of said second base station; and   transmitting using a downlink broadcast communications channel said third uplink loading factor, wherein said first and second uplink interference reports have been determined as a function of said transmitted first, second, and third uplink loading factors.   
     
     
         13 . The method of  claim 5 , wherein said first base station transmits uplink loading factors in accordance with a downlink transmission recurring schedule, wherein said first base station allocates uplink segments to said first wireless terminal to transmit uplink interference reports in accordance with a recurring uplink schedule, and wherein uplink interference reports from said first wireless terminal are scheduled to be received at a higher frequency than an uplink loading factor corresponding to an attachment point is scheduled to be transmitted. 
     
     
         14 . The method of  claim 5 , wherein the first and second interference reports are beacon ratio reports. 
     
     
         15 . The method of  claim 9 , wherein broadcasting at least some of said received second base station loading factor information includes:
 transmitting said at least some second base station loading factor information using orthogonal frequency division multiplexing signals.   
     
     
         16 . A first base station for use in a multiple access wireless communications system including a plurality of base stations, each of said plurality of base stations including at least one base station attachment point, the first base station comprising:
 at least one processor configured to:
 receive second base station loading factor information indicative of loading of a second base station attachment point corresponding to a second base station; and 
 control the first base station to broadcast at least some of said received second base station loading factor information, broadcasting being dependent on the level of loading of the base stations; and 
   memory coupled to said at least one processor.   
     
     
         17 . The first base station of  claim 16 ,
 wherein said second base station is physically adjacent said first base station; and   wherein said at least one processor is configured to receive said second base station loading factor information via a backhaul link between said first and second base station.   
     
     
         18 . The first base station of  claim 16 ,
 wherein said second base station is physically adjacent said first base station; and   wherein said at least one processor is configured to receive said second base station loading factor information from a mobile communications device which received said second base station loading factor information over a wireless communications link with said second base station.   
     
     
         19 . The first base station of  claim 16 , wherein said at least one processor is further configured to determine a first uplink loading factor indicative of uplink loading for a first base station attachment point, said first base station attachment point corresponding to the first base station. 
     
     
         20 . The first base station of  claim 19 , wherein said at least one processor is further configured to:
 receive from a first wireless terminal a first uplink interference report and receive from a second wireless terminal a second uplink interference report; and   allocate uplink resources as a function of said received first and second uplink interference reports.   
     
     
         21 . The first base station of  claim 20 ,
 wherein said memory stores received loading factor information and said first and second uplink interference reports, said first and second uplink interference reports being a function of said transmitted first and second uplink loading factors.   
     
     
         22 . The first base station of  claim 21 , wherein said at least one processor is further configured to control the generation of at least one of beacon and pilot channel signals to be broadcast as a first broadcast signal; and
 wherein said first uplink interference report is a function of a received power level measured by the first wireless terminal of said first broadcast signal, the first uplink loading factor, a received power level measurement by the first wireless terminal of a second broadcast signal from the second base station, and the second uplink loading factor.   
     
     
         23 . A first base station for use in a multiple access wireless communications system including a plurality of base stations, each of said plurality of base stations including at least one base station attachment point, the first base station comprising:
 means for receiving second base station loading factor information indicative of loading of a second base station attachment point corresponding to a second base station; and   means for broadcasting at least some of said received second base station loading factor information, said means for broadcasting being configured to broadcast depending on the level of loading of the base stations.   
     
     
         24 . The first base station of  claim 23 ,
 wherein said second base station is physically adjacent said first base station; and   wherein said means for receiving is configured to receive said second base station loading factor information via a backhaul link between said first and second base stations.   
     
     
         25 . The first base station of  claim 23 ,
 wherein said second base station is physically adjacent said first base station; and   wherein said first base station further includes means for wirelessly receiving second base station loading factor information from a mobile communications device which received said second base station loading factor information over a wireless communications link with said second base station.   
     
     
         26 . The first base station of  claim 23 , further comprising:
 means for determining a first uplink loading factor indicative of uplink loading for a first base station attachment point, said first base station attachment point corresponding to the first base station.   
     
     
         27 . The first base station of  claim 26 , further comprising:
 means for wirelessly receiving, from a first wireless terminal, a first uplink interference report and for wirelessly receiving, from a second wireless terminal, a second uplink interference report; and   means for allocating uplink resources as a function of said received first and second uplink interference reports.   
     
     
         28 . The first base station of  claim 27 , further comprising:
 means for storing received loading factor information and said first and second uplink interference reports, said first and second uplink interference reports being a function of said transmitted first and second uplink loading factors.   
     
     
         29 . The first base station of  claim 26 , wherein said first and second base station include multiple sectors and wherein said second base station attachment point corresponds to one carrier of one sector of said second base station. 
     
     
         30 . A non-transitory computer readable medium including executable instructions for use in a first base station in a multiple access wireless communications system, the non-transitory computer readable medium comprising:
 instructions for causing at least one computer to receive second base station loading factor information indicative of loading of a second base station attachment point corresponding to a second base station; and   instructions for causing the at least one computer to broadcast at least some of said received second base station loading factor information, said broadcast being depending on the level of loading of the base stations.