A method , comprising: receiving , by a processor of a user equipment, UE, from a base station one or more reference signals, which are non-zero power, NZP, or zero power, ZP, on one or more time-frequency resources indicated by a network via a communication link between the UE and the base station; estimating , by the processor based on the receiving, a subspace spanned by a channel response of an interfering signal; determining , by the processor, a precoding matrix indicator, PMI, based on the estimated subspace, wherein the PMI indicates precoders for a plurality of spatial layers with respect to the communication link, and a single channel quality indicator, CQI, associated with the plurality of spatial layers; and transmitting , by the processor, to the base station a channel state information, CSI, feedback comprising at least the PMI and the CQI, wherein the CSI feedback further comprises information related to a signal quality of each spatial layer of the plurality of spatial layers by indicating one or more layer indexes sorted in a sorted order based on signal quality of each of the plurality of spatial layers such that: when the sorted order is a descending order, the index value for a first spatial layer having a higher signal quality is reported before the index value for a second spatial layer having a lower signal quality, and when the sorted order is an ascending order, the index value for a first spatial layer having a lower signal quality is reported before the index value for a second spatial layer having a higher signal quality. receiving , by a processor of a user equipment, UE, from a base station one or more reference signals, which are non-zero power, NZP, or zero power, ZP, on one or more time-frequency resources indicated by a network via a communication link between the UE and the base station; estimating , by the processor based on the receiving, a subspace spanned by a channel response of an interfering signal; determining , by the processor, a precoding matrix indicator, PMI, based on the estimated subspace, wherein the PMI indicates precoders for a plurality of spatial layers with respect to the communication link, and a single channel quality indicator, CQI, associated with the plurality of spatial layers; and transmitting , by the processor, to the base station a channel state information, CSI, feedback comprising at least the PMI and the CQI, wherein the CSI feedback further comprises information related to a signal quality of each spatial layer of the plurality of spatial layers by indicating one or more layer indexes sorted in a sorted order based on signal quality of each of the plurality of spatial layers such that: when the sorted order is a descending order, the index value for a first spatial layer having a higher signal quality is reported before the index value for a second spatial layer having a lower signal quality, and when the sorted order is an ascending order, the index value for a first spatial layer having a lower signal quality is reported before the index value for a second spatial layer having a higher signal quality. when the sorted order is a descending order, the index value for a first spatial layer having a higher signal quality is reported before the index value for a second spatial layer having a lower signal quality, and when the sorted order is an ascending order, the index value for a first spatial layer having a lower signal quality is reported before the index value for a second spatial layer having a higher signal quality. <EOS>