Patterns optimized demodulation reference signals

A method of determining values ​​of cyclic CS shift, and code orthogonal covering, OCC, associated with reference signals demodulation, DMRS for a plurality of transmission layers and carrier component by a device in a communication system wireless operation employing multiple input multiple output, MIMO, and carrier aggregation, the method comprising: receiving (102) a value (1) n DMRS cyclic shift semi-static, CS, which is updated on an infrequent basis; receiving (104) An index value nDMRS dynamic CS; obtaining a value (2) nD2MRS dynamic nDMRS CS corresponding to index value received dynamic CS indexing table that maps a predetermined value (2) nD2MRS regarding nDMRS values ​​and values ​​OCC; obtaining a value (OCC) nDMRS orthogonal covering code, OCC corresponding to nDMRS index value received dynamic CS index the predetermined table; using (2) nD2MRS y) (OCC nDMRS to encode DMRS for layer 0; encode DMRS for each of the other layers by: derivation of a value of CS to each of the other layers by (a) adding a first deviation specific layer (2) nD2MRS; and (b) adding (1) DMRS n the result of step (a); calculating a value of OCC for each of the other layers by adding (OCC) nDMRS a second deflection specific OCC layer; encode DMRS for all other layers using the value of CS derived for each layer and the values ​​of OCC calculated for each layer wherein within the predetermined table values ​​(2) nD2MRS CS are arranged in two or more sets of values ​​(2) nD2MRS CS values ​​(2) nD2MRS CS within each set separated by the predetermined minimum deviation being, and wherein the DMRS for a first carrier component comprising values CS from a first set of the two om ost sets and DMRS for a second carrier comprising CS values ​​from a second set of two or more sets.