Code-reuse partitioning systems and methods for cellular communications

Abstract

Time slots of a plurality of time-division multiple access (TDMA) cellular radiotelephone base stations are synchronized. Cellular radiotelephone frequencies are allocated among the plurality of base stations according to a first frequency allocation system in a first synchronized time slot and according to a second frequency allocation system in a second synchronized time slot. Each frequency allocation system may include an adaptive channel allocation system, a frequency reuse system, a frequency reuse partitioning system or a fixed frequency reuse system. Spreading codes of a plurality of code-division multiple access (CDMA) cellular radiotelephone base stations are synchronized. Cellular radiotelephone frequencies are allocated among the plurality of base stations according to a first frequency allocation system for a first synchronized spreading code and according to a second frequency allocation system for a second synchronized spreading code. Each frequency allocation system may include an adaptive channel allocation system, a frequency reuse system, a frequency reuse partitioning system or a fixed frequency reuse system. Cellular radiotelephone systems and methods affording increased base station channel capacity, more efficient spectrum utilization and improved equipment migration are thus provided.

That which is claimed:  
     
         1 . A cellular radiotelephone system comprising: 
 a plurality of time division multiple access (TDMA) cellular radiotelephone base stations, each of which serves a cellular radiotelephone cell and communicates radiotelephone communications with cellular radiotelephones using radiotelephone communications signals communicated over a like plurality of sequential time slots;    time-slot synchronizing means for synchronizing said like plurality of sequential time slots among said plurality of base stations, such that a corresponding time slot for each base station is used concurrently, to produce synchronized time slots among said plurality of base stations; and    time-reuse partitioning means for allocating cellular radiotelephone frequencies among said plurality of base stations in a first one of said synchronized time slots according to a first frequency allocation system and for allocating cellular radiotelephone frequencies among said plurality of base stations in a second one of said synchronized time slots according to a second frequency allocation system different from said first frequency allocation system.    
     
     
         2 . A system according to    claim 1    wherein said first frequency allocation system is one of a first adaptive channel allocation system, a first frequency reuse system, a first frequency reuse partitioning system and a first fixed frequency reuse system, and wherein said second frequency allocation system is one of a second adaptive channel allocation system, a second frequency reuse system, a second frequency reuse partitioning system and a second fixed frequency reuse system.  
     
     
         3 . A system according to    claim 1   : 
 wherein said first frequency allocation has a number of subscribers; and    wherein said time-reuse partitioning means further comprises means responsive to said number of subscribers of said first frequency allocation system for allocating cellular radiotelephone frequencies among said plurality of base stations according to said first frequency allocation system in a third one of said synchronized time slots.    
     
     
         4 . A system according to    claim 1    further comprising means for receiving a request for a service type from a cellular radiotelephone and wherein said time reuse partitioning means comprises means for allocating frequencies responsive to a received request for a service type.  
     
     
         5 . A system according to    claim 4    wherein said service type comprises one of a digital speech service, a digital data service, a packet data service, a control message service, a facsimile service, an image service and a code division multiple access (CDMA) service.  
     
     
         6 . A system according to    claim 1    wherein said time reuse partitioning means comprises means for allocating cellular radiotelephone frequencies from a first frequency pool in a first one of said synchronized time slots and for allocating cellular radiotelephone frequencies from a second frequency pool different from said first frequency reuse pool in a second one of said synchronized time slots.  
     
     
         7 . A system according to    claim 6    further comprising means for receiving a request for a service type from a cellular radiotelephone served by one of said plurality of base stations and wherein said time reuse partitioning means assigns said first synchronized time slot, corresponding to said first frequency reuse pool, to the cellular radiotelephone responsive to a request for a first service type and to said second time synchronized time slot, corresponding to said second frequency reuse pool, to the cellular radiotelephone responsive to a request for a second service type.  
     
     
         8 . A system according to    claim 7   : 
 wherein said first service type comprises digital voice service and said second service type comprises a packet data service; and    wherein said first frequency reuse pool comprises all available frequencies in the cellular radiotelephone system and said second frequency pool comprises frequencies unused in adjacent cells.    
     
     
         9 . A system according to    claim 7    wherein said first service type comprises a wideband service and said second service type comprises a narrowband service; and 
 wherein said first frequency pool comprises a plurality of wide frequency bands and said second frequency pool comprises a plurality of narrow frequency bands.  
 
     
     
         10 . A system according to    claim 9    wherein said wideband service comprises a high speed data service and wherein said narrow service comprises one of a digital voice service and a low speed digital data service.  
     
     
         11 . A system according to    claim 9    wherein said wideband service comprises a code division multiple access (CDMA) service.  
     
     
         12 . A cellular radiotelephone system comprising: 
 a plurality of code division multiple access (CDMA) cellular radiotelephone base stations for communicating with cellular radiotelephones on a plurality of frequencies using a plurality of spreading codes, each of said plurality of spreading codes having a period;    code synchronizing means for synchronizing said plurality of spreading codes among said plurality of base stations so that said periods of each of said plurality of spreading codes are concurrent, to produce synchronized spreading codes among said plurality of base stations; and    code-reuse partitioning means for allocating cellular radiotelephone frequencies among said plurality of base stations for a first one of said synchronized spreading codes according to a first frequency allocation system and for allocating frequencies among said plurality of base stations for a second one of said synchronized spreading codes according to a second frequency allocation system different from said first frequency allocation system.    
     
     
         13 . A cellular radiotelephone system according to    claim 12    wherein said plurality of spreading codes is one of a plurality of direct-sequence-modulation codes, a plurality of frequency-hopping codes, and a plurality of combined frequency-hopping/direct-sequence-modulation codes.  
     
     
         14 . A system according to    claim 12    wherein said first frequency allocation system is one of a first adaptive channel allocation system, a first frequency reuse system, a first frequency reuse partitioning system and a first fixed frequency reuse system, and wherein said second frequency allocation system is one of a second adaptive channel allocation system, a second frequency reuse system, a second frequency reuse partitioning system and a second fixed frequency reuse system.  
     
     
         15 . A system according to    claim 12   : 
 wherein said first frequency allocation has a number of subscribers; and    wherein said code-reuse partitioning means further comprises means responsive to said number of subscribers of said first frequency allocation system for allocating cellular radiotelephone frequencies among said plurality of base stations according to said first frequency allocation system for a third one of said synchronized spreading codes.    
     
     
         16 . A method for operating a plurality of time division multiple access cellular radiotelephone base stations, each of which communicates with cellular radiotelephones using a like plurality of sequential time slots, the method comprising: 
 allocating cellular radiotelephone frequencies among said plurality of base stations according to a first frequency allocation system in a first one of said time slots and according to a second frequency allocation system different from said first frequency allocation system in a second one of said time slots.    
     
     
         17 . A method according to    claim 16    wherein said step of allocating is preceded by a step of synchronizing said like plurality of sequential time slots among said plurality of base stations, such that a corresponding time slot for each base station is used concurrently, to produce synchronized time slots among said plurality of base stations.  
     
     
         18 . A method according to    claim 17    wherein said step of allocating comprises a step of allocating cellular radiotelephone frequencies among said plurality of base stations according to one of a first adaptive channel allocation system, a first frequency reuse system, a first frequency reuse partitioning system and a first fixed frequency reuse system in said first one of said synchronized time slots and according to one of a one of a second adaptive channel allocation system, a second frequency reuse system, a second frequency reuse partitioning system and a second fixed frequency reuse system in said second one of said synchronized time slots.  
     
     
         19 . A method according to    claim 17    wherein said step of allocating further comprises the step of allocating cellular radiotelephone frequencies among said plurality of base stations according to said first frequency allocation in a third one of said synchronized time slots to thereby adapt to increasing users of said first frequency allocation system.  
     
     
         20 . A method for operating a plurality of code division multiple access cellular radiotelephone base stations for communicating with cellular radiotelephones using a plurality of spreading codes each of said spreading codes having a period, the method comprising the steps of: 
 allocating cellular radiotelephone frequencies among said plurality of base stations according to a first frequency allocation system for a first one of said spreading codes and according to a second frequency allocation system different from said first frequency allocation system for a second one of said spreading codes.    
     
     
         21 . A method according to    claim 20    wherein said step of allocating is preceded by a step of synchronizing said plurality of spreading codes among said plurality of base stations so that said periods of said plurality of spreading codes are concurrent, to produce synchronized spreading codes among said plurality of base stations.  
     
     
         22 . A method according to    claim 20    wherein said step of allocating comprises a step of allocating cellular radiotelephone frequencies among said plurality of base stations according to one of a first adaptive channel allocation system, a first frequency reuse system, a first frequency reuse partitioning system and a first fixed frequency reuse system for said first one of said synchronized spreading codes and according to one of a one of a second adaptive channel allocation system, a second frequency reuse system, a second frequency reuse partitioning system and a second fixed frequency reuse system for said second one of said synchronized spreading codes.  
     
     
         23 . A cellular radiotelephone base station for a cellular radiotelephone cell which communicates with cellular radiotelephones using radiotelephone communications signals communicated over a plurality of sequential time slots using frequencies allocated to the base station for each time slot of the plurality of sequential time slots, the base station comprising: 
 first processing means responsive to a first type of radiotelephone communications signals communicated during a first group of sequential time slots of said plurality of sequential time slots, for processing said first type of radiotelephone communications signals to thereby recover radiotelephone communications; and    second processing means responsive to a second type of radiotelephone communications signals different from said first type of radiotelephone communications signals and communicated during a second group of time slots, for processing said second type of radiotelephone communications signals to thereby recover radiotelephone communications.    
     
     
         24 . A base station according to    claim 23   : 
 wherein said first processing means comprises means for processing narrowband radiotelephone communications signals; and    wherein said second processing means comprises means for processing wideband communications signals.    
     
     
         25 . A base station according to    claim 24    wherein said means for processing wideband communications signals comprises means for despreading code division multiple access (CDMA) radiotelephone communications signals.  
     
     
         26 . A base station according to    claim 23   : 
 wherein said first processing means comprises means for processing digital voice radiotelephone communications signals; and    wherein said second processing means comprises means for processing packet data radiotelephone communications signals.    
     
     
         27 . A base station according to    claim 26    wherein said means for processing packet data radiotelephone communications signals comprises means for canceling interference.  
     
     
         28 . A base station according to    claim 23    wherein said first and second processing means comprise: 
 receiving means, responsive to cellular radiotelephones, for receiving radiotelephone communications signals from a cellular radiotelephone over a plurality of signal paths; and  
 means for processing radiotelephone communications signals received by said receiving means.  
 
     
     
         29 . A base station according to    claim 28    wherein said means for processing radiotelephone communications signals comprises: 
 first means for combining the received radiotelephone communications signals which are received from a first direction; and  
 second means for combining the received radiotelephone communications signals which are received from a second direction.