Wireless communication system and data transmitter

A wireless communication system comprising:

• a first radio equipment that transmits first data using a first radio wave;
• a data transmitter that transmits a second radio wave, the second radio wave causing a disturbance on the first radio wave according to second data to be transmitted;
• and
• a second radio equipment that demodulates the first data transmitted from the first radio equipment, and demodulates the second data transmitted from the data transmitter using a variation in a bit error rate of communication between the first radio equipment and the second radio equipment, wherein
• the data transmitter includes:
• a first antenna that receives the first radio wave;
• an amplifier that amplifies a signal corresponding to the first radio wave received by the first antenna;
• a feedback element that feedbacks a signal from an output node of the amplifier to an input node of the amplifier, and forms a feedback loop;
• a modulator that modulates the signal in the feedback loop according to the second data;
• and
• a second antenna that transmits the signal in the feedback loop as the second radio wave.