Patent ID: 8780832
Filing Date: 2014-07-15
Classification: H04J,H04L,H04W

Abstract:
1. A method in a radio network node for transmitting a reference signal over an antenna port to a user equipment (UE), wherein the reference signal is transmitted in a code division multiplexing (CDM) group, the CDM group comprising at least two CDM subgroups, each CDM subgroup being transmitted on a different subcarrier, each CDM subgroup comprising resource elements, wherein the method comprises the steps of: transmitting the reference signal over a first CDM subgroup using an orthogonal cover code, the first CDM subgroup comprising a first set of resource elements related to the reference signal in a first time slot and a second set of resource elements related to the reference signal in a subsequent time slot; selecting a permutation of the orthogonal cover code; and transmitting the reference signal over a second CDM subgroup using the permutation of the orthogonal cover code, the second CDM subgroup comprising a third set of resource elements related to the reference signal in the first time slot and a fourth set of resource elements related to the reference signal in the second time slot, wherein