Channel covariance matrix conversion

A method of obtaining a downlink (DL) covariance matrix of a communication channel, the method comprising:

• computing, by a base station device, an angular power spectrum (APS) of an antenna array of the base station device based on an uplink (UL) covariance matrix of the communication channel and a UL response of the antenna array, wherein computing the APS of the antenna array comprises computing a solution to a feasibility problem which includes a determined constraint to find a vector that is an element of a plurality of sets constructed with measurements of the UL covariance matrix;
• and
• computing, by the base station device, the DL covariance matrix of the communication channel based on the APS and a DL response of the antenna array.

A non-transitory computer-readable medium having processor-executable instructions stored thereon for obtaining a downlink (DL) covariance matrix of a communication channel, wherein the processor-executable instructions, when executed, facilitate:

• computing, by a base station device, an angular power spectrum (APS) of an antenna array of the base station device based on an uplink (UL) covariance matrix of the communication channel and a UL response of the antenna array, wherein computing the APS of the antenna array comprises computing a solution to a feasibility problem which includes a determined constraint to find a vector that is an element of a plurality of sets constructed with measurements of the UL covariance matrix;
• and
• computing, by the base station device, the DL covariance matrix of the communication channel based on the APS and a DL response of the antenna array.