Distributed computation of precoding weights for coordinated multipoint transmission on the downlink

A transmit signal processor for coordinating transmissions from a plurality of coordinating cells in a coordinated multipoint cell, said transmit signal processor configured to:

• compute tentative precoding weights for a coordinated multipoint transmission from a plurality of transmit antennas in two or more coordinating cells of said coordinated multipoint cell to one or more mobile terminals in a serving cell of the coordinated multipoint cell, at least one of said transmit antennas being shared with an overlapping coordinated multipoint cell;
• determine a power availability for said shared transmit antennas in said coordinated multipoint cell;
• and
• scale the tentative precoding weights based on the power availability of said shared transmit antennas to determine final precoding weights for said coordinated multipoint transmission.

A method implemented by a transmit signal processor for coordinating multipoint transmissions in a mobile communication network having coordinated multipoint cells that overlap, said method comprising:

• receiving, from serving cells in two or more coordinated multipoint cells, transmit power requirements for one or more transmit antennas shared by said two or more coordinated multipoint cells;
• determining power availability for each shared transmit antenna based on said received transmit power requirements;
• and
• reporting said power availability for each shared antenna to said serving cells.

A transmit signal processor for coordinating multipoint transmissions in a mobile communication network having coordinated multipoint cells that overlap, said transmit signal processor configured to:

• receive, from serving cells in two or more coordinated multipoint cells, transmit power requirements for one or more transmit antennas shared by said two or more coordinated multipoint cells;
• determine power availability for each shared transmit antenna based on said received transmit power requirements;
• and
• report said power availability for each shared antenna to said serving cells.