Periodic channel state information reporting for time division duplex (tdd) carrier aggregation systems

A method for reporting periodic channel state information (CSI), the method comprising:

• determining a reporting period (Npd) of a user equipment (UE) for a serving cell;
• identifying a Time-Division Duplex (TDD) uplink-downlink (UL-DL) configuration of a primary cell of the UE;
• transmitting a periodic CSI report for the serving cell, from the UE to the eNB, using a physical uplink control channel (PUCCH) on the primary cell according to the reporting period;
• and
• using the reporting period of Npd=1 for the serving cell if the TDD UL-DL configuration of the primary cell is one of 0, 1, 3, 4, or 6 and all UL subframes of the primary cell in a radio frame are used for periodic CSI reporting.

A non-transitory computer readable medium encoded with computer executable instructions, which when accessed, cause a machine to perform operations comprising:

• determining a reporting period (Npd) of a user equipment (UE) for a serving cell;
• determining a Time-Division Duplex (TDD) uplink-downlink (UL-DL) configuration of a primary cell of the UE;
• transmitting a periodic CSI report for the serving cell, from the UE to the eNB, using a physical uplink control channel (PUCCH) on the primary cell according to the reporting period;
• and
• using the reporting period of Npd=1 for the serving cell if the TDD UL-DL configuration of the primary cell is one of 0, 1, 3, 4, or 6 and all UL subframes of the primary cell in a radio frame are used for periodic CSI reporting.