Implementation of Anti-Interference and High-Speed Underwater Acoustic Communication via Chip-Level Parallel Ghost Imaging

Ghost imaging (GI) by utilizing spatial or time correlation has provided a distinctive route for remote reconstruction of information. For underwater acoustic communication, the GI shows unique advantages in high-fidelity and secure transfer of information despite the random and time-varying noises everywhere in water. However, GI has severe limitation in information transmission rates due to the gigantic volume of sampling. Here the parallel GI is proposed to implement anti-interference and high-speed underwater acoustic communication. To minimize the local disturbance of acoustic fields and improve measurement accuracy, a chip-scale sensor with the size of 5 × 5 mm² and the thickness of ≈600 µm is fabricated. At the frequency of 7 kHz, the device sensitivity can reach -140 dB re 1 rad/µPa. In parallel GI, one signal sequence that carries three-channel information is first launched via the speckle multiplexing technology, all of which can then be well decoded at the receiving end through the GI algorithm. The experiment shows that in an underwater surrounding of 50 dB noises, the information transmission rate can reach up to 1080 bit/s for parallel GI under 4000 sampling times.