Radio-frequency output level compensating circuit of portable radio transceiver

A radio-frequency output level compensating circuit for a radio transmitter, comprising:

• a radio transmitting device having a first power amplifier for power-amplifying an input radio-frequency signal for generating an amplified radio-frequency signal at a transmitting level corresponding to an input automatic power control level, first transmitting means coupled to an output terminal of said first power amplifier for radio-transmitting said amplified radio-frequency signal, first transmitting output control means for supplying a first automatic power control voltage corresponding to a voltage of a predetermined output level to said first power amplifier, and controlling a first transmitting output with said first automatic power control voltage in response to an input of a connection detecting signal, a first battery having a first battery voltage, and first power driving means for supplying said first battery voltage as an operational supply voltage of the respective circuits in said radio transmitting device;
• a radio-frequency signal compensating device having a second power amplifier for power-amplifying an input radio-frequency signal up to a transmitting level corresponding to an input automatic power control voltage level, second transmitting means coupled to an output terminal of said second power amplifier for radio transmitting said amplified radio-frequency signal, second transmitting output control means for supplying a second automatic power control voltage to said second power amplifier in response to an the input of said voltage of predetermined output level, a second battery having a second battery voltage greater than said first battery voltage, and second power driving means for regulating said second battery voltage to said voltage of predetermined output level and supplying the regulated voltage as an operational voltage of the respective units in said radio-frequency signal compensating device;
• and
• connecting means for connecting the voltage of predetermined output level to said first transmitting output control means and connecting an output of said first transmitting means to an input of said second power amplifier, and at the same time, providing said connection detecting signal to said first transmitting output control means.

An apparatus for a radio transceiver having a portable radio telephone operating at a predetermined transmission power level and a radio-frequency compensating means, said apparatus comprising:

• a curly cord for connecting said portable radio telephone to said radio-frequency compensating means;
• said portable radio telephone being operable in response to a supply voltage, said portable radio telephone comprising:
• a first antenna;
• a first battery for supplying a first battery voltage;
• a first power driver for receiving said first battery voltage and for controlling an output of said first battery voltage as said supply voltage in response to a first switching control signal;
• first transmitting output control means for generating an output level selecting voltage, for receiving a predetermined output level control voltage, for outputting one of said output level selecting voltage and said predetermined output level control voltage as a reference voltage in response to a connection signal provided in response to said curly cord connecting said portable radio telephone to said radio-frequency compensating means, for receiving a first feedback voltage, and for generating a first automatic power control voltage in response to an amplified difference between said reference voltage and said first feedback voltage;
• a first power amplifier for receiving a radio-frequency signal and for power amplifying said radio-frequency signal in response to said first automatic power control voltage for generating a first amplified radio-frequency signal having said predetermined transmission power level;
• a first output detector for detecting the level of said first amplified radio-frequency signal to generate said first feedback voltage;
• and
• first transmission means for radio transmitting said first amplified radio-frequency signal;
• said radio-frequency compensating means comprising:
• a second antenna;
• a second battery for supplying a second battery voltage, said second battery voltage being greater than said first battery voltage;
• a second power driver receiving said second battery voltage, and for controlling an output of said second battery voltage to a voltage regulator and said first power driver in response to a second switching control signal, said voltage regulator for converting said second battery voltage to a voltage value equal to said first battery voltage;
• second transmitting output control means for generating a second automatic power control voltage in response to an amplified difference between said output level selecting voltage generated by said first transmitting means and a second feedback voltage;
• means for receiving said first amplified radio-frequency signal output from said first transmission means and for supplying said amplified radio-frequency signal to a second power amplifier;
• said second power amplifier for generating a second amplified radio-frequency signal in response to said second automatic power control voltage, said second amplified radio-frequency signal having said predetermined transmission power level;
• a second output detector for detecting the level of said second amplified radio-frequency signal to generate said second feedback voltage;
• and
• second transmission means supplying said second amplified radio-frequency signal to said second antenna for radio transmitting said second amplified radio frequency signal.