| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a transmitter having a function for optimizing a noise level of transmitter noise or the like while taking into account the newly enacted standards of unwanted radiation of a radio unit. <P>SOLUTION: A digital wireless transmitter is equipped with a non-linear distortion compensation circuit using a Cartesian negative feedback linearizer, wherein variable attenuators 8, 21 are provided, respectively in a part of a forward circuit and a feedback circuit of transmission output. The digital wireless transmitter is further equipped with a means 25 for detecting spurious power in a predetermined frequency band of the transmission output and a control means 24 for adjusting a forward direction and/or feedback direction gain by means of the variable attenuators on the basis of a result of detection performed by the means, thereby reducing an increase in noise in the predetermined frequency band of the transmission output. <P>COPYRIGHT: (C)2009,JPO&INPIT |
