Digital Hydrophone Signal Acquisition and Analysis for KM3NET

The KM3NeT project foresees the utilization of hydrophones for various purposes such as positioning calibration, oceanographic measurements and possibly neutrino detection. Hydrophones will be connected to the Control Logic Board (CLB) inside Optical Modules, were incoming data will be acquired, packed and sent to the On-Shore station. It is planned to use hydrophones with a digital output, encoded with the AES3 protocol with a sample rate of 192 kHz and an amplitude resolution of the signal of 24 bits. This output is directly provided by the digital hydrophone, or by a digitizer in case of an analog one. The present document will report the result of the interfacing of a digital hydrophone to the Kintex 7 FPGA describing hardware and firmware; in case of the utilization of an analog hydrophone for the final design, there will probably be modifications in the hardware, while the firmware part can be the same in both cases.