Abstract: An electronic device and a voice recognition method thereof are provided. A voice recognition method of an electronic device includes receiving trigger voice, storing a characteristic of the trigger voice for voice verification by analyzing the trigger voice. When a user issues a voice command, determining whether the user voice command comprises the characteristic belonging to the trigger voice, and performing function of the electronic device corresponding to the user voice command based on the determination. Accordingly, users may easily use the voice recognition function of the electronic device.

Abstract: Provided is an apparatus for adjusting an envelope signal delay in an envelope-tracking power amplifier. The apparatus includes: an envelope signal providing unit configured to provide an envelope signal; a variable negative group delay unit configured to adjust a group delay of the envelope signal received from the envelope signal providing unit and output the adjusted envelope signal; an envelope modulator configured to modulate the envelope signal outputted from the variable negative group delay unit; a group delay difference detecting unit configured to detect a group delay difference between the envelope signal which is outputted from the envelope signal providing unit and the envelope signal which is outputted from the envelope modulator; and a control signal generating unit configured to generate a control signal to control a group delay value of the variable negative group delay unit according to the group delay difference.

Abstract: Provided is an apparatus for adjusting an envelope signal delay in an envelope-tracking power amplifier. The apparatus includes: an envelope signal providing unit configured to provide an envelope signal; a variable negative group delay unit configured to adjust a group delay of the envelope signal received from the envelope signal providing unit and output the adjusted envelope signal; an envelope modulator configured to modulate the envelope signal outputted from the variable negative group delay unit; a group delay difference detecting unit configured to detect a group delay difference between the envelope signal which is outputted from the envelope signal providing unit and the envelope signal which is outputted from the envelope modulator; and a control signal generating unit configured to generate a control signal to control a group delay value of the variable negative group delay unit according to the group delay difference.

Abstract: Provided are a power amplifier and a method thereof. The power amplifier power amplifier includes: a main amplifying unit receiving power; an auxiliary amplifying unit connected in parallel to the main amplifying unit; and a Balun transformer combined with the main amplifying unit and the auxiliary amplifying unit. Respectively different bias voltages are applied to the main amplifying unit and the auxiliary amplifying unit.

Abstract: Provided are a power amplifier and a method thereof. The power amplifier power amplifier includes: a main amplifying unit receiving power; an auxiliary amplifying unit connected in parallel to the main amplifying unit; and a balloon transformer combined with the main amplifying unit and the auxiliary amplifying unit. Respectively different bias voltages are applied to the main amplifying unit and the auxiliary amplifying unit.