Design Of Transponder In Ultra-short Baseline Acoustic Positioning System

In the shallow water oil exploration，the acoustic positioning technology isused in acoustic positioning system for measurement and secondarypositioning to seismic exploration cables, then completed the exploration ofthe undersea oil and gas resources. The USBL positioning system due to thesmall size of its acoustic array, removable positioning and easy to install, etc.are widely adopted in shallow water oil exploration. Meanwhile, theunderwater acoustic transponder of the underwater part in the USBLpositioning system is fixed on the seabed exploration cable to providemeasurement data and answer the positioning signal.Because of the limitations of short positioning distance and unablemulti-target positioned that the domestic acoustic positioning system have inshallow sea oil exploration, the design and implementation of acoustictransponder based on MSP430Micro Controller Unit (MCU) and DigitalSignal Processor (DSP) was proposed. The hardware has a low-power designin device selection, duty circuit design and power amplifier efficiency, whichreduced the standby power consumption of the transponder; Weak signalextraction were analyzed in detail that enhance the capacity of the anti-jamming; and the high-performance; low-power16-bit fixed-point digitalsignal processor TMS320VC5509A also provides a reliable computingplatform for communications algorithms. The gold sequence direct sequencespread-spectrum was adopted on communication system that improved theirability of anti-multipath and anti-decay, and be able to completemulti-responder response and positioning, improved the effectiveness of thework.MATLAB-based simulations and experiments were carried out. The resultsshow that the transponder has a good performance at supporting multi-targetpositioned in1500m communication distance, and the standby quiescentcurrent is less than5mA, which reached the anticipated design index.