| 摘要 |
A method for determining an optimum non-uniform constellation is described. The method comprises the step of performing a first process, the first process comprising the steps of: based on use of a first uniform constellation 901; determining a Signal-to-Noise Ratio (SNR) value as the lowest SNR 905 at which a Bit Error Rate (BER) 903 is lower than a threshold value, wherein the BER is a BER achieved using the first constellation and using a defined transmission system, wherein the defined transmission system is defined by a set of one or more system parameter values; and determining a second non-uniform constellation having the best performance 907a within the defined transmission system at the determined SNR value according to a predetermined performance measure, such as capacity. The process may be iteratively performed using the determined second constellation as input into the first process as the first constellation in the next iteration until the SNR is minimised. The constellations may be Quadrature Amplitude Modulation (QAM) constellations. |
