Patent ID: 7933325

Claim:
An antenna driving apparatus operated by power supplied from a power source and generates a signal transmitted via an antenna, the antenna driving apparatus comprising: a control circuit, which generates a pulsed control signal based on a pulsed transmission signal; and an amplifier circuit, which is supplied with power from the power source and generates an output signal to be sent to the antenna based on the control signal, wherein the control circuit changes the pulse width of the control signal based on the level of the output signal or the voltage of the power source, and wherein the control circuit includes: a pulse generating circuit which generates a pulse signal having a pulse width corresponding to the level of the output signal or the voltage of the power source; and a control signal generating circuit which synthesizes the pulse signal and the pulsed transmission signal to generate the control signal having the pulse width corresponding to the level of the output signal or the voltage of the power source.