Abstract:
An apparatus and method for estimating a direction of an RF signal are provided. The apparatus includes an antenna unit, a preliminary correction unit, a signal processing unit, a conversion unit, and a signal direction estimation unit. The antenna unit receives an RF signal from at least one antenna. The preliminary correction unit performs preliminary correction depending on whether the at least one antenna is an antenna having directional gain. The signal processing unit generates an analog signal by performing a frequency shift on the RF signal or a signal on which the preliminary correction has been performed. The conversion unit converts the analog signal into a digital sample. The signal direction estimation unit extracts the phase of the antenna from the digital sample, and estimates the direction of the RF signal based on the extracted phase.
Abstract:
An apparatus and method for preventing an electronic device from recording. The apparatus includes a control unit for generating a first modulation signal and controlling the components of the apparatus; a first modulation unit for modulating the first modulation signal to an FM signal; an ultrasonic signal generation unit for generating an ultrasonic signal, the frequency of which is adjusted by changing the value of at least one of a variable resistor and a variable capacitor depending on the magnitude of the FM signal; an amplification unit for increasing or decreasing the magnitude of the ultrasonic signal; a resonance unit for increasing the voltage to be applied to a transducer by generating resonance; and an ultrasound output unit for converting electrical signals into ultrasonic signals using the transducer and radiating a recording prevention signal, converted into the ultrasonic signal, to the microphone of an electronic device.