Inter-eNB over-the-air calibration for reciprocity-based coordinated multipoint communications

An apparatus comprising:

• a transceiver configured to:
• transmit a calibration participation rule to enable wireless communication devices to determine whether to participate in an uplink-downlink (UL-DL) reciprocity calibration;
• receive a first uplink (UL) calibration reference signal (RS) and a first DL channel estimate associated with a first communication link between a first transmission point (TP) and a first wireless communication device when the first communication link satisfies the calibration participation rule;
• and
• transmit a DL coordinated multipoint (CoMP) joint transmission signal according to the UL-DL reciprocity calibration;
• and
• a processor configured to determine the UL-DL reciprocity calibration based on at least the first DL channel estimate and a first UL channel estimate determined based on the first UL calibration RS.

A non-transitory computer-readable medium having program code recorded thereon, the program code comprising:

• code for causing a central unit to transmit a calibration participation rule to enable wireless communication devices to determine whether to participate in an uplink-downlink (UL-DL) reciprocity calibration;
• receiving, by the central unit, a first uplink (UL) calibration reference signal (RS) and a first DL channel estimate associated with a first communication link between a first transmission point (TP) and a first wireless communication device when the first communication link satisfies the calibration participation rule;
• code for causing the central unit to determine the UL-DL reciprocity calibration based on at least the first DL channel estimate and a first UL channel estimate determined based on the first UL calibration RS;
• and
• code for causing the central unit to transmit a DL coordinated multipoint (CoMP) joint transmission signal according to the UL-DL reciprocity calibration.