Neighbor List Distribution for Smart Mobility

Abstract

A user equipment UE receives from a serving cell indications of frequency bands supported by neighbor cells/frequencies, and at least one individual neighbor cell/frequency supports a plurality of frequency bands. The neighbor cells/frequencies are filtered to retain only those which are indicated to support a frequency band or frequency bands which are also supported by the UE. Examples are given of various system information blocks for sending the frequency band indications to the UE. In one embodiment they are arranged in an information element IE having an entry for each of the neighbor cells/frequencies and a list of frequency bands for each entry. In another the IE has an index and an associated frequency band(s) where a value of the index indicates that one or more of the neighbor cells/frequencies referred to by the index belong to the associated frequency band(s).

1 . An apparatus comprising at least one processor; and
 at least one memory including computer program code;   in which the at least one memory and the computer program code is configured, with the at least one processor, to cause the apparatus at least to:   receive from a serving cell indications of frequency bands supported by neighbor cells or frequencies, in which there is at least one individual neighbor cell or frequency for which there is indicated a plurality of frequency bands supported; and   filter the neighbor cells or frequencies to retain only those which are indicated to support a frequency band or frequency bands which are also supported by a user equipment.   
     
     
         2 . The apparatus according to  claim 1 , in which the indications are received in system information broadcast by the serving cell and the at least one individual neighbor cell or frequency is a neighbor cell or frequency to the serving cell. 
     
     
         3 . The apparatus according to  claim 2 , in which the system information comprises at least one of system information block types  11 ,  11 bis,  12 ,  19  and  3 . 
     
     
         4 . The apparatus according to  claim 1 , in which the received indications are arranged in an information element having an entry for each of the neighbor cells or frequencies and a list of frequency bands for each entry. 
     
     
         5 . The apparatus according to  claim 1 , in which the received indications are arranged in an information element having an index and one or more associated frequency bands, in which a value of the index indicates that one or more of the neighbor cells or frequencies referred to by the index belong to the one or more frequency bands associated with the index. 
     
     
         6 . The apparatus according to  claim 1 , in which the apparatus comprises the user equipment which is configured to utilize only the filtered neighbor cells or frequencies for cell reselection. 
     
     
         7 . A method, comprising:
 receiving from a serving cell indications of frequency bands supported by neighbor cells or frequencies, in which there is at least one individual neighbor cell or frequency for which there is indicated a plurality of frequency bands supported; and   filtering the neighbor cells or frequencies to retain only those which are indicated to support a frequency band or bands which are also supported by a user equipment.   
     
     
         8 . The method according to  claim 7 , in which the indications are received in system information broadcast by the serving cell. 
     
     
         9 . The method according to  claim 7 , in which the received indications are arranged in an information element having an entry for each of the neighbor cells or frequencies and a list of frequency bands for each entry. 
     
     
         10 . The method according to  claim 7 , in which the received indications are arranged in an information element having an index and one or more associated frequency bands, in which a value of the index indicates that one or more of the neighbor cells or frequencies referred to by the index belong to the one or more frequency bands associated with the index. 
     
     
         11 . A memory tangibly storing a computer program that is executable by at least one processor, in which the computer program comprises:
 code for receiving in system information broadcast by a serving cell indications of frequency bands supported by neighbor cells, in which there is at least one individual neighbor cell for which there is indicated a plurality of frequency bands supported; and   code for filtering the frequency bands to retain only those indicated frequency bands which are also supported by a user equipment.   
     
     
         12 . The memory according to  claim 11 , in which the received indications are arranged in an information element having an entry for each of the neighbor cells and a list of frequency bands for each entry. 
     
     
         13 . The memory according to  claim 11 , in which the received indications are arranged in an information element having an index and one or more associated frequency bands, in which a value of the index indicates that one or more of the neighbor cells or frequencies referred to by the index belong to the one or more frequency bands associated with the index. 
     
     
         14 . An apparatus comprising
 at least one processor; and   at least one memory including computer program code;   in which the at least one memory and the computer program code is configured, with the at least one processor, to cause the apparatus at least to:   obtain frequency bands supported by neighbor cells or frequencies, in which there is at least one individual neighbor cell or frequency which supports a plurality of frequency bands; and   send to user equipments indications of the frequency bands associated with the respective neighbor cells or frequencies that support them, including the plurality of frequency bands supported by the at least one individual neighbor cell or frequency.   
     
     
         15 . The apparatus according to  claim 14 , in which the indications are sent to the user equipments in system information broadcast by the apparatus which comprises a serving cell, and the at least one individual neighbor cell or frequency is a neighbor cell or frequency to the serving cell. 
     
     
         16 . The apparatus according to  claim 15 , in which the system information comprises at least one of system information block types  11 ,  11 bis,  12 ,  19  and  3 . 
     
     
         17 . The apparatus according to  claim 14 , in which the at least one memory and the computer program code is configured with the at least one processor to cause the apparatus to send to the user equipments the indications by:
 arranging the indications in an information element having an entry for each of the neighbor cells or frequencies and a list of frequency bands for each entry; and   sending the information element in system information.   
     
     
         18 . The apparatus according to  claim 14 , in which the at least one memory and the computer program code is configured with the at least one processor to cause the apparatus to send to the user equipments the indications by:
 arranging the indications in an information element having an index and one or more associated frequency bands, in which a value of the index indicates that one or more of the neighbor cells or frequencies referred to by the index belong to the one or more frequency bands associated with the index; and   sending the information element in system information.   
     
     
         19 . A method comprising:
 obtaining frequency bands supported by neighbor cells or frequencies, in which there is at least one individual neighbor cell or frequency which supports a plurality of frequency bands; and   sending to user equipments indications of the frequency bands associated with the respective neighbor cells or frequencies that support them, including the plurality of frequency bands supported by the at least one individual neighbor cell or frequency.   
     
     
         20 . The method according to  claim 19 , in which the indications are sent to the user equipments in broadcast system information, and the at least one individual neighbor cell is an neighbor cell or frequency to a serving cell executing the method. 
     
     
         21 . The method according to  claim 19 , in which sending to the user equipments the indications comprises:
 arranging the indications in an information element having an entry for each of the neighbor cells or frequencies and a list of frequency bands for each entry; and   sending the information element in system information.   
     
     
         22 . The method according to  claim 19  or  20 , in which sending to the user equipments the indications comprises:
 arranging the indications in an information element having an index and one or more associated frequency bands, in which a value of the index indicates that one or more of the neighbor cells or frequencies referred to by the index belong to the one or more frequency bands associated with the index; and 
 sending the information element in system information. 
 
     
     
         23 . A memory tangibly storing a computer program that is executable by at least one processor, in which the computer program comprises:
 code for obtaining frequency bands supported by neighbor cells or frequencies, in which there is at least one individual neighbor cell or frequency which supports a plurality of frequency bands; and   code for sending to user equipments indications of the frequency bands associated with the respective neighbor cells or frequencies that support them, including the plurality of frequency bands supported by the at least one individual neighbor cell or frequency.