METHOD AND APPARATUS FOR OPTIMAL REDUNDANCY VERSION (RV) SELECTION FOR UMTS HSDPA TRANSMISSIONS

摘要

A method and apparatus for identifying optimal redundancy version (RV) sequences for HSDPA transmissions based on extensive search. In a first embodiment of the present invention, in HSDPA QPSK mode, the transmitter retransmits according to the RV sequence [0 7 3 4 1 6 5 2] and in HSDPA 16QAM mode, the transmitter retransmits according to the RV sequence [0 1 3 4 5 6 7 1]. In a second embodiment of the present invention, in HSDPA QPSK mode, the transmitter retransmits according to the RV sequence [0 7 3 4 1 6 5 2] if the initial coding rate is greater than or equal to 0.5 and [0 4 3 6 2 1 6 2] if the initial coding rate is less than 0.5. In HSDPA 16QAM mode, the transmitter retransmits according to the RV sequence [0 1 3 4 5 6 7 1] if the initial coding rate is greater than or equal to 0.5 and the transmitter retransmits according to the RV sequence [0 4 5 6 0 4 5 6] if the initial coding rate is less than 0.5. In a third embodiment of the present invention, the transmitter retransmits according to the RV sequence according to each specific initial coding rate. In a fourth embodiment of the present invention, the transmitter retransmits according to the RV sequence according to a specific initial coding rate and a specific mother code rate. An SNR tracking algorithm is provided in conjunction with the optimal sequences for robust HARQ operations.