Transmission power control circuit in radio transmitter

Abstract

Abstract PURPOSE:To attain transmission power control under any temperature condition by providing a control means using a correction value corresponding to an output of a temperature sensing means to apply correction to the control signal thereby applying temperature compensation stably and simply. CONSTITUTION:A detection diode 3 detects an output voltage of a power amplifier 1, converts the voltage into a DC voltage, an A/D converter 4 applies A/D conversion to an output of a detection diode 3, a control circuit 5 compares the standard bit pattern of the power control signal with a bit pattern outputted from the A/D converter 4 and outputs a bit difference when any bit difference exists. The detection characteristic decrease of the detection diode 3 is given in advance to the control circuit 5, a thermister 9 senses the ambient temperature and the power control signal bit is corrected by using a correction value (bit) depending on the ambient temperature at that time. Thus, the temperature compensation is executed stably and simply under any temperature condition.

Inventors

• 👤 Toshiyuki Okada

Bibliographic Details