Patent ID: 8976890
Filing Date: 2015-03-10
Classification: H04L

Abstract:
1. A multilevel amplitude modulation device for generating, from digital data, a multilevel amplitude modulation signal having four or more signal levels and outputting the generated signal, the modulation device comprising: an average level calculator operable to select one of a plurality of preliminarily prepared different candidates for a code word building method such that an average signal level of a symbol array, obtained by adding a symbol for a code word of digital data to be transmitted to one or more already outputted symbols included in a multilevel amplitude modulation signal already outputted, is most approximate to voltage center of the four or more signal levels, and output a selection signal indicating the selected code word building method; a signal converter operable to form a code word of the digital data in accordance with the code word building method indicated by the selection signal; and a multilevel modulator operable to generate a multilevel amplitude modulation signal with use of the code word and output the generated multilevel amplitude modulation signal.