HARQ APPARATUS AND METHOD FOR VARYING RETRANSMISSION POWER IN MOBILE COMMUNICATION SYSTEM

摘要

PURPOSE: An HARQ(Hybrid Automatic Repeat Request) apparatus and a method for varying retransmission power in a mobile communication system are provided to reduce a repeat number and to minimize a power consumption by effectively controlling the retransmission power. CONSTITUTION: A mobile station(600) is used for a mobile communication system which repeats a transmission of packet data and related data when error generated in pre-transmitted packet data and combines the re-transmitted packet data with the pre-transmitted packet data to modulate the result. The mobile station retransmits required packet data. The mobile station includes an AMC(Adaptive Modulation and Coding) and retransmission power controller(619) and a power controller(621). The AMC and retransmission power controller calculates a required SNR(Signal to Noise Ratio), which is required for the retransmission, by using a target SNR, which is required for a frame error to have a predetermined value, and an SNR of the erroneous packet data which is calculated from a channel quality monitoring value from a terminal. The AMC and retransmission power controller further calculates retransmission power from the required SNR. The power controller controls the transmission power of a packet according to the retransmission power calculated at the AMC and retransmission power controller.