Apparatus for generating frequency signal

A transmitter, comprising:

• a base band unit adapted to generate a digital signal of a base band;
• a digital analog converter adapted to convert the digital signal of the base band into an analog signal;
• a first mixer;
• a radio frequency filter adapted to filter a specific frequency band of a transmitting signal output from the mixer;
• a power amplifier adapted to amplify and transmit a signal output from the radio frequency filter;
• a radio frequency unit adapted to transmit an output signal from the power amplifier through an antenna;
• and
• a frequency signal generation unit, the frequency signal generation unit, including:
• a control circuit adapted to generate a frequency generation signal, an assistance frequency select signal, a sign select signal, and a dividing select signal;
• a reference frequency signal generator adapted to generate a first frequency signal and generate a second frequency signal by dividing the generated first frequency signal;
• an assistance frequency signal generator adapted to generate a third frequency signal, generate fourth and fifth frequency signals by dividing the third frequency signal by a different division ratio, and generate a sixth frequency signal from the fourth and fifth frequency signals in response to the assistance frequency select signal;
• a mixer adapted to select a sign of the sixth frequency signal in response to the sign select signal and generate a seventh frequency signal and a eighth frequency signal by mixing the sixth frequency signal of the selected sign and the first frequency signal;
• a switch adapted to output the seventh frequency signal or the eight frequency signal in response to the dividing select signal;
• and
• a first divider adapted to output a ninth frequency signal by dividing the eighth frequency signal received from the switch, the first divider being coupled to the switch,
• wherein the first mixer is adapted to mix a transmitting signal output from the digital analog converter and at least one of the frequency signals output by the frequency signal generation unit.

A frequency signal generation unit, comprising:

• controlling means for generating a frequency generation signal, an assistance frequency select signal, a sign select signal, and a dividing select signal;
• reference frequency signal generating means for generating a first frequency signal and a second frequency signal by dividing the generated first frequency signal;
• assistance frequency signal generating means for generating a third frequency signal, fourth and fifth frequency signals by dividing the third frequency signal by a different division ratio, and a sixth frequency signal from the fourth and fifth frequency signals in response to the assistance frequency select signal;
• mixing means for selecting a sign of the sixth frequency signal in response to the sign select signal and generate a seventh frequency signal and a eighth frequency signal by mixing the sixth frequency signal of the selected sign and the first frequency signal;
• switching means for outputting the seventh frequency signal or the eight frequency signal in response to the dividing select signal;
• and
• first dividing means for outputting a ninth frequency signal by dividing the eighth frequency signal received from the switching means.