Underwater acoustics is a part of many marine projects. some scientists use sound to track ocean currents,identify potential obstacles,or quantify fish distributions.other part of research don't directly ise sound,but listen to ocean noise or investicate how marine animals produce and hear sounds.The noise level does not depend on the direction in which the wind is blowing. Waves do not break at lower wind speeds. Wind is one of the most important components of weather and climate. Winds are the primary driver of large-scale ocean currents. They are responsible for the formation of the Gulf Stream, for example. Improved understanding of the global pattern of wind is needed to improve weather and climate forecasting. Information on wind over the ocean helps meteorologists, oceanographers, and climatologists. Ambient noise data were collected for the period of six months in the shallow water of Arabian sea.Datas were collected for different wind speed ranges between 0.5 m/s to 7 m/s and the analysis were performed for frequencies ranging from 500 Hz to 7 KHz. The relative spectral energy distribution of sea noise is presented for a number of wind speeds .Linear relationship between the sea noise spectrum levels and the wind speed were found for the entire frequency range.

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Bit Error Rate is an essential parameter to quantize the effectiveness of transceiver circuits used in low power, low duty cycle sensor nodes. BER can figure out their performance in terms of number of retransmissions, which keeps the node to consume its battery power undesirably rather than conserving it. Forward Error Correction schemes ensure the transceiver circuit to effectively perform its operations over a noisy bandwidth like ISM and under harsh/unpredictable channel conditions. As none of the coherent M-ary modulation schemes are 100% efficient, non-coherent schemes can be considered as power-efficient choice for power limited sensor nodes. BFSK helps the sensor no des to have quicker transition from sleep mode to active mode. Otherwise, this will also force the transceiver to waste considerable amount of power. In this paper, by developing a SIMULINK model for RS (7, 3) coded BFSK in its non-coherent detection mode is analyzed for its bit error rate performance under various channel and coding conditions. Simulation results show that, this model gives its best BER performance as 16.67% under suitable conditions.