Patent ID: 6904099
Filing Date: 2005-06-07
Classification: H04L

Abstract:
1. A digital modulation signal generating apparatus, comprising: a band signal generator which generates a base band signal; a carrier signal generator which generates a carrier signal; an orthogonal modulator which generates a digital modulation signal of a predetermined channel that corresponds to a frequency of the carrier signal upon receipt of the base band signal generated by the base band signal generator and the carrier signal generated by the carrier signal generator; an amplifier which amplifies the digital modulation signal generated by the orthogonal modulator; an output terminal which outputs the digital modulation signal amplified by the amplifier; a first level varying member provided between the base band signal generator and the orthogonal modulator, which varies a level of the base band signal, and inputs the base band signal which has had the level varied to the orthogonal modulator; a second level varying member provided between the amplifier and the output terminal, which attenuates and varies a level of an output signal output from the amplifier, and outputs the output signal which has had the level attenuated and varied from the output terminal; output level specifying member which specifies an output level value of the digital modulation signal output from the output terminal; a judgment section which judges whether or not the output level value of the digital modulation signal specified by the output level specifying member is higher than a predetermined value or a predetermined range; and a level diagram switching section which sets the first level varying member and the second level varying member so that the digital modulation signal output from the output terminal is a predetermined attenuation quantity value which makes desired carrier leak characteristics compatible with desired mutual modulation distortion characteristics, respectively, based on the output level value of the digital modulation signal specified by the output level specifying member and a judgment result caused by the judgment member.