Method for managing heterogeneous base stations in a wireless network

Abstract

A method and devices are provided to enable operation while experiencing reduced interference of at least two base stations in a wireless network wherein at least one of base stations is deployed in a femto deployment configuration and at least one of the others is deployed in a different deployment category. The method comprises preventing the usage of at least one radio resource selected from among sub-carriers comprised within a radio channel and/or time-domain resource, from one of the at least two base stations.

1 . In a wireless network comprising at least one base station and at least one subscriber device operative to communicate therewith, and at least one other base station and at least one subscriber device operative to communicate therewith, a method for allocating radio resources for control channels to enable reducing interference to communications transmitted from each of the base stations and received by its respective at least one subscriber terminal, wherein said method comprises, for at least one of said base stations, transmitting control information at pre-defined intervals in at least one of the downlink radio frames, wherein said control information transmitted by each of said at least two base stations is associated with communications transmitted from said base station and received by its respective at least one subscriber terminal, and wherein at least one downlink radio frame transmitted by at least one of said at least two base stations comprises:
 in a single frequency channel and/or one or more adjacent frequency channels thereof, at least one radio resource allocation for control channels, carrying control information, is provided for transmitting downlink control information associated with the respective one of the at least two base stations, and wherein said at least one radio resource allocation is used only by at least one base station that is of a different deployment category than the other base station;   and wherein the at least one radio resource allocation for the at least one control channel is selected for one of the at least two base stations within the at least one downlink radio frame, based upon at least one of the following:
 (i) the deployment category associated with said one base station if two different deployment categories are defined for said at least two base stations; and 
 (ii) minimum interference assessment by said one base stations. 
   
     
     
         2 . The method according to  claim 1 , wherein said minimum interference assessment is carried out by each base station by measuring interference experienced in a receive state within the at least one radio resource allocation for control channels, at pre-defined time intervals. 
     
     
         3 . The method according to  claim 1 , wherein said minimum interference assessment is carried out by measuring power levels of communications generated by the at least one other base station and/or at least one other subscriber terminal, while operating in a transmit state within the at least one radio resource allocation for the at least one control channel, at pre-defined time intervals. 
     
     
         4 . The method according to  claim 1 , wherein the minimum interference assessment is used as one of the criteria for selecting the at least one radio resource allocation for the at least one transmit and/or receive control channel. 
     
     
         5 . A wireless femto base station comprising a processor configured to prevent transmission during some downlink time intervals and/or sub-carriers, to reduce interference to communications exchanged between at least one other base station of a different deployment category and its respective one or more subscriber terminals. 
     
     
         6 . A wireless base station comprising:
 at least one transceiver operative to transmit control information within at least one pre-defined radio resource in at least one of the downlink radio frames, wherein said control information is associated with communications transmitted from said base station; and   a processor configured to provide at least one downlink radio frame for transmission by said transceiver, said downlink radio frame comprising:   in a single frequency channel and/or one or more adjacent frequency channels thereof, at least one radio resource for transmitting at least one control channel comprising downlink control information associated with said base station;   wherein said radio resource allocation for the at least one control channel for downlink transmission is characterized by being associated each with at least one pre-defined sub-carrier partition within the corresponding single frequency channel and/or adjacent frequency channel thereof, and/or by being associated with one or more predefined time intervals;   and wherein at least one of said radio resource allocation for at least one control channel is prevented from being used by at least one another base station either in any of the sub-carrier domain and/or in the time domain.   
     
     
         7 . A wireless subscriber terminal comprising:
 at least one transceiver operative to receive from an associated base station, control information at predefined intervals in at least one downlink radio frame, wherein said control information is associated with communications transmitted from said base station; and   a processor configured to provide at least one uplink radio frame for transmission by said transceiver wherein in a single frequency channel and/or an adjacent frequency channel thereof, at least one radio resource allocation is prevented from being used for radio transmissions to a base station deployed in a deployment category other than said base station.