Patent ID: 8923229

Claim:
A method comprising: receiving an uplink resource allocation that grants an uplink resource to a plurality of user equipments, and an indication in the uplink resource allocation of a cyclic shift; sending data on the granted uplink resource; mapping the granted uplink resource to a downlink resource in dependence on the indicated cyclic shift, wherein the mapping is such that for a predetermined number of user equipments being allocated a same uplink resource in a single multi-user multiple input multiple output uplink resource allocation, each ones of said predetermined number of user equipments which map to an adjacent downlink resource exhibit an optimized cyclic shift relative to one another, and wherein the cyclic shift is for a demodulation reference signal and the indication of the cyclic shift is a dynamic cyclic shift indicator of three bits that indicates a relative cyclic shift in a cell in which the plurality of user equipments operate; and tuning a receiver to receive on the mapped downlink resource an indication about the sent data.