A method, in abase station of a wireless telecommunications system comprising multiple radiating elements, the method comprising modifying a number of uplink or downlink information streams, each information stream corresponding to an element in a space sampling basis for the system, wherein, in the downlink, the space sampling basis is configured so that the number of information streams is the same as the number of radiating elements of the system, and in the uplink, the space sampling basis is configured using a composite antenna derived from multiple radiating elements of the system to form a synthesised beam.