METHOD AND DEMODULATOR FOR CALCULATING LOG-LIKELIHOOD RATIO IN A QUADRATURE AMPLITUDE MODULATION METHOD

摘要

PURPOSE: A method and demodulator for calculating log-likelihood ratio is provided to reduce the power consumption while maintaining the probability of a modulation symbol error.;CONSTITUTION: A constellation storage unit(120) stores a constellation point which is arranged in triangle shape and a modulation symbol matched in the constellation point. A conversion unit(110) extracts a receiving symbol in a wireless signal. A log-likelihood ratio calculation unit(130) performs exponential calculation for a difference between the receiving symbol and the modulation symbol. The log-likelihood ratio calculation unit distributes the exponential calculated value as a group by the value of the k-th bit.;COPYRIGHT KIPO 2011