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Titanium nitride (TiN) materials have gained an interest over the past years due to their unique characteristics, such as thermal stability, extreme hardness, low production cost, and comparable optical properties to gold. In the present study, TiN nanoparticles were synthesized via a thermal benzene route to obtain black nanoparticles. Scanning electron microscopy (SEM) was carried out to examine the morphology. Further microscopic characterization was done where the final product was drop cast onto double-sided conductive carbon tape and sputter-coated with gold/palladium at a thickness of 4 nm for characterization by field emission scanning electron microscopy (FE-SEM) with energy dispersive X-Ray spectroscopy (EDS) that revealed they are spherical. ImageJ software was used to measure the average size of the particles to be 79 nm in diameter. EDS was used to determine the elements present in the sample and concluded that there were no impurities. Further characterization by Fourier Transform infrared (FTIR) spectroscopy was carried out to identify the characteristic peaks of TiN. X-ray diffraction (XRD) revealed typical peaks of cubic phase titanium nitride, and crystallite size was determined to be 14 nm using the Debye-Scherrer method. Dynamic light scattering (DLS) analysis revealed the size distribution of the TiN nanoparticles, with nanoparticles averaging at 154 nm in diameter. Zeta potential concluded the surface of the TiN nanoparticles is negatively charged. 

JANUS is a physical layer communication standard for underwater acoustic communications published by North Atlantic Treaty Organization (NATO) in 2017. Instead of the nominal frequency band of 9440 – 13600 Hz specified in the standard, we adopt the JANUS packet for a high frequency band spanning from 96 kHz to 134 kHz. We also add cargo packets in the same frequency band using JANUS fast mode with a symbol rate of 23 ksps. Experiments were conducted in a swimming pool and the JANUS 3.0.5 Matlab version of the example receiver program was used to process the JANUS packets. We found that the example receiver program uses many fix(), round() and floor() functions which lead to synchronization errors. After modifying the simple rx code and fixing the error, our JANUS decoding results show that the adopted JANUS fast mode successfully achieves carrier and frame synchronization in all cases despite some bit errors remaining in the JANUS packet in severe multipath scenarios.