An apparatus for a communication system, the apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to: determine a first measurement of first reference signals associated with a first analog beam used to receive the first reference signals, determine a second measurement of second reference signals associated with a second analog beam used to receive the second reference signals, determine first information characterizing a digital beamformer based on the first measurement and the second measurement.