is determined by p dmrs p pdsch m n note that the tables are constructed assuming maximum of 8 transmission layers is supported in the cell if the maximum supported number of layers is fewer than 8 e g 4 is also a typical configuration then the resultant tables are clearly just subsets of the tables shown here upon receiving the message index the ue determines the total number 48 of layers being used by the enb and the number 50 of layers assigned to cdm group 1 and 2 from the appropriate mapping table 52 table 1 or table 2 using the total number of layers used and the number of layers assigned to cdm groups 1 and 2 the power ratio 54 between the dm rs and data pdsch symbols can be determined from the appropriate mapping table 56 table 4 using this embodiment the following information is signalled to each ue to reduce the signalling overhead each unique power ratio in table 4 can be mapped to an index an example is shown in table 5 for maximum of 8 transmission layers note that some entries in the table are not necessary and hence can be removed if the maximum number of transmission layers supported in the cell is smaller the mapping between rank and dm rs port index as shown in table 3 is also defined all tables are known to all ues and.