| 摘要 |
PROBLEM TO BE SOLVED: To provide totally stabilized transmission characteristics not to be changed by the change of a transmission power. SOLUTION: Concerning an orthogonal digital base band signal generated by a base band signal generating circuit 1, the band width and attenuation characteristics thereof are limited in a band by a variable base band limiting part 2, this signal is converted into an analog signal by a D/A converting part 3 and orthogonally modulated by an orthogonal modulating circuit 4, the frequency thereof is converted into the signal of a carrier band by a frequency converting circuit 5 and this signal is amplified by a gain controllable high frequency amplifier circuit 6 and transmitted from an antenna 7. In this case, a detection circuit 8 detects the output power of a present channel or leak power of an adjacent channel and corresponding to the result, the band width and attenuation characteristics of the base band limiting filter are controlled. |
