Transmitting data to a network node, and receiving data from a network node using grassmann constellations

An apparatus for transmitting data to a network node, the apparatus comprising:

• processing circuitry;
• and
• memory, the memory containing instructions executable by the processing circuitry, wherein the apparatus is configured to perform a process comprising:
• selecting, based on the data to be transmitted to the network node, one of a plurality of reference signal symbol sequences, wherein the reference signal symbol sequences correspond to constellation points on a Grassmannian manifold, and each of the reference signal symbol sequences has a phase such that a sum of inner products of pairs of the reference signal symbol sequences in at least a subset of the reference signal symbol sequences is a maximum;
• and
• transmitting the selected reference signal symbol sequences to the network node.

An apparatus for receiving data from a network node, the apparatus comprising:

• processing circuitry;
• and
• memory, the memory containing instructions executable by the processing circuitry, wherein the apparatus is configured to perform a process comprising:
• receiving, from the network node, a reference signal symbol sequence of a plurality of reference signal symbol sequences, wherein the reference signal symbol sequences correspond to constellation points on a Grassmannian manifold, and each of the reference signal symbol sequences has a phase such that a sum of inner products of pairs of the reference signal symbol sequences in at least a subset of the reference signal symbol sequences is a maximum;
• and
• determining, based on the reference signal symbol sequence, the data transmitted by the network node.