Apparatuses, methods, and systems are disclosed for determining a precoder for wireless communications. An apparatus includes a processor that determines a precoder for a set of modulation symbols, the determined precoder comprising a plurality of codewords and configured to reduce an ensemble interference and a pairwise interference among the plurality of codewords. The processor precodes the set of modulation symbols based on the determined precoder. The processor maps the precoded set of modulation symbols to a set of physical transmission resources for a transmission layer, wherein a number of modulation symbols in the set of modulation symbols is greater than a number of physical transmission resources in the set of physical transmission resources. The apparatus includes a transceiver that transmits, to a receiver node, an indication of the determined precoder and the set of physical transmission resources.