| 摘要 |
A method and system are provided for determining the best combination of modulation control information and reference signal design to be used by a transmitter so as to maximise a channel quality indication e.g. maximise throughput. The modulation control information is used by the transmitter node to convert source data into an information bearing signal, and the information bearing signal is combined with a reference signal conforming to the reference signal design in order to produce the transmit signal. The modulation control information may define a Modulation and Coding Scheme (MCS), constellation mapping or channel coding to be used by the transmitter. The reference signal design defines the form of the pilot/reference signal to be used and may specify a pilot signal density (including location of the pilot symbols in the transmitted signal) or transmit power, for example. The method comprises checking all possible combinations to determine a predicted Block Error Rate (BLER) S50 for each combination to find the combination providing the maximum throughput, or goodput, which is selected S80. Re-selection may take place based on triggers. The method comprises (a) selecting a candidate reference signal design S20 from a plurality of candidate reference signal designs, (b) determining channel state information for the channel S25, (c) determining, from the channel state information, signal to noise ratio information S30 for said channel, and (d) for each S65 of a plurality of candidate modulation control information S40, using the signal to noise ratio information to determine a quality indication S50, S55 (e.g. goodput) for said channel. Steps (a) to (d) are then repeated S75 for each candidate reference signal design in said plurality. Thereafter a winning quality indication is selected S80 from the determined quality indications, and the combination of candidate reference signal design and candidate modulation control information associated with the winning quality indication is then output to, and used by, the transmitting node. |
