Transmitting apparatus and transmitting method
View Patent ↗A transmitting apparatus and a transmitting method wherein the systematic bit reception quality can be improved and the throughput performance can be improved. An IR parameter control part ( 101 ) controls, based on the number of retransmissions, the ratio of systematic bits to parity bits in mapping them to packets, and controls to map a parity bit to an initially transmitted packet, while mapping a systematic bit to a retransmitted packet. An encoding part ( 102 ) generates the systematic bits and parity bits and maps them to the packets in accordance with the IR parameters. A transmission power calculating part ( 105 ) calculates, based on reception quality information of the initially transmitted packet fed back from a receiving end, the transmission power of the transmitted packet to which the systematic bit is mapped. A transmission power control part ( 106 ) controls the transmission power of the retransmitted packet such that it is equal to the transmission power as calculated by the transmission power calculating part ( 105 ).
1. A transmitting apparatus comprising:
a coding section that performs coding processing of transmission data and generates systematic bits and parity bits;
an incremental redundancy parameter controlling section that controls an incremental redundancy parameter representing a rate of mapping the systematic bits and the parity bits in transmission units and controls the coding section to map the parity bits in a first transmission unit and the systematic bits in a second transmission unit transmitted after the first transmission unit; and
a transmission power controlling section that controls transmission power for the second transmission unit based on received quality information for the first transmission unit fed back from a receiving side.
2. The transmitting apparatus according to claim 1 , wherein the incremental redundancy parameter controlling section controls mapping the systematic bits in the first transmission unit with the parity bits.
3. The transmitting apparatus according to claim 1 , wherein the transmission power controlling section controls transmission power for the first transmission unit lower than the transmission power for the second transmission unit.
4. The transmitting apparatus according to claim 1 , wherein, when the received quality information for the first transmission unit fed back from the receiving side is equal to or lower than a predetermined value, the transmission power controlling section sets an offset for the transmission power for the second transmission unit.
5. The transmitting apparatus according to claim 1 , wherein, when as a result of transmission power control for the second transmission unit the transmission power for the second transmission unit exceeds a maximum transmission power, the transmission power controlling section controls the transmission power for the second transmission unit to the maximum transmission power.
6. The transmitting apparatus according to claim 1 , wherein, the transmission power controlling section uses transmission power control commands as the received quality information, and controls the transmission power for the second transmission unit based on a total number of “up's” commanding an increase of transmission power in the transmission power control commands and a total number of “down's” commanding a decrease of transmission power in the transmission power control commands, in a predetermined period.
7. The transmitting apparatus according to claim 6 , wherein, upon acquiring reliability information for a transmission power control command, the transmission power controlling section decides whether or not to use the transmission power control command in controlling the transmission power for the second transmission unit based on the reliability information.
8. The transmitting apparatus according to claim 1 , wherein the transmission unit comprises a packet or a frame of a concatenate transmission time interval scheme.
9. A transmitting method, comprising:
an incremental redundancy controlling step of controlling an incremental redundancy parameter representing a rate of mapping the systematic bits and the parity bits in transmission units and controlling mapping the parity bits in a first transmission unit and the systematic bits in a second transmission unit transmitted after the first transmission unit; and
a transmission power controlling step of controlling transmission power for the second transmission unit based on received quality information of the first transmission unit fed back from a receiving side.