Chaotic digital CDMA was invented by Tao Yang

Tao Yang (Wuxi)

Tao Yang is a computer scientist. He attended Tongji University, where he received his Bachelor's degree in 1990 and his Master's degree in 1993. He has invented fuzzy cellular neural networks in 1995,computational verb in 1997,...

 and Leon O. Chua

Leon O. Chua

Leon Ong Chua is an IEEE Fellow and a professor in the electrical engineering and computer sciences department at the University of California, Berkeley, which he joined in 1971...

 of the University of California, Berkeley

University of California, Berkeley

The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...

 in 1997. This is a chaotic spread spectrum

Spread spectrum

Spread-spectrum techniques are methods by which a signal generated in a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth...

 CDMA communication technology where the message signal is first scrambled by an RF

Radio frequency

Radio frequency is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents which carry radio signals...

 chaotic carrier and then sent to the receiver. Many users can share the same communication channel while each other can get their own signal via using unique chaotic carriers. There was a USA patent

Patent

A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....

for this technology.