Downlink symbol-level precoding as part of multiuser MISO communication

A network node for downlink symbol-level precoding as part of multiuser MISO communication, the network node comprising processing circuitry, the processing circuitry being configured to cause the network node to:

• obtain a data vector, d[n], of a current time instant, n, to be precoded, wherein the data vector comprises data symbols, d1[n], . . . , dK[n], for K>1 users, and wherein the current time instant corresponds to a single symbol;
• and
• precode the obtained data vector by determining an output vector, x[n], for the data vector of the current time instant n, wherein, determining the output vector for the current time instant comprises searching for a data vector d[m] of a previous time instant, m, that is co-linear with the data vector of the current time instant according to a co-linearity factor, and when such a data vector of the previous time instant is found, the output vector is equal to an output vector x[m] of the previous time instant multiplied with the co-linearity factor.

A computer program product for downlink symbol-level precoding as part of multiuser MISO communication, the computer program product comprising a non-transitory computer readable storage medium storing computer code which, when run on processing circuitry of a network node, causes the network node to:

• obtain a data vector, d[n], of a current time instant, n, to be precoded, wherein the data vector comprises data symbols, d1[n], . . . , dK[n], for K>1 users, and wherein the current time instant corresponds to a single symbol;
• and
• precode the obtained data vector by determining an output vector, x[n], for the data vector of the current time instant n, wherein, determining the output vector for the current time instant comprises searching for a data vector d[m] of a previous time instant, m, that is co-linear with the data vector of the current time instant according to a co-linearity factor, and when such a data vector of the previous time instant is found, the output vector is equal to an output vector x[m] of the previous time instant multiplied with the co-linearity factor.