Bit soft value normalization

摘要

An LTE uplink soft demapper includes an SC-FDMA symbol noise power meter (22) configured to individually determine a noise power measure for each SC-FDMA symbol in a slot by exploiting information contained in modulated data symbols of the corresponding SC-FDMA symbol. A bit soft value normalizer (24) connected to the SC-FDMA symbol noise power meter (22) is configured to normalize bit soft values, representing reliability of received bits obtained from the SC-FDMA symbols in the slot, based on the determined noise power measures.

主权项

1. An LTE uplink bit soft value normalization method for Log-Max based de-mapping, including the steps of:
de-mapping modulated data symbols of each corresponding SC-FDMA symbol in a slot to un-normalized bit soft values that are independent of noise power; individually determining a noise power measure for each said SC-FDMA symbol in the slot by exploiting noise information carried within modulated data symbols of the corresponding SC-FDMA symbol, wherein said exploiting is based on using a statistical model that describes the statistical distribution of received modulated data symbols obtained from received SC-FDMA symbols; and individually normalizing each of the un-normalized bit soft values, said normalized bit soft values representing reliability of received bits obtained from the SC-FDMA symbols in the slot, based on the determined noise power measures for each corresponding SC-FDMA symbol.