| 摘要 |
PROBLEM TO BE SOLVED: To prevent transmission power from becoming excessive in a mobile communication terminal to which precise transmission power control is required. SOLUTION: A branching filter 11, a detection circuit 12 and a smoothing circuit 18 generate detection voltage corresponding to the average transmission power of a mobile communication terminal. A threshold setting circuit 14 generates threshold voltage corresponding to permitted maximum average transmission power. A voltage comparator 15 compares detection voltage with threshold voltage and judges whether average transmission power is larger than or smaller than maximum average transmission power. A control circuit 16 changes control voltage so that the gain of a variable gain amplifier 4 is reduced when the voltage comparator 15 judges that average transmission power is larger than maximum average transmission power.
|
