An altitude controlled profiler for use in coastal waters, comprising: a thruster and an altitude controller configured to control altitude, wherein a thrust of the thruster neutralizes upwardly directed buoyant force and the altitude controller is configured to maintain a user defined constant altitude above sea bed; an upward looking echo-sounder mounted on one of rear fins and used to measure surface wave profiles in a hover mode; a pressure sensor provided at an end-plate behind a nose-cone to operate in the hover mode; an acoustic modem mounted on another rear fin and used to communicate with a profiler from a surface craft; extra fins used to minimize rotation of the profiler about its own axis; a digital camera and a strobe light secured at the nose cone and diametrically opposite to each other; and a second echo-sounder mounted at a vertex of the nose cone and being connected to electronic circuits, wherein the altitude controller is coupled to the second echo-sounder for receiving altitude information, and coupled to the pressure sensor for receiving pressure information, characterised in that the altitude controller comprising: a Linear Quadratic Regulator configured to provide a low pass filter that rejects high frequency components; an integrator placed close to the thruster configured to remove biases in the pressure sensor and the thruster; and a second order complementary filter in a feedback loop, configured for complimenting altitude information from the echo-sounder with negative time derivative (-dz/dt) of depth measured from the pressure sensor for enabling the rejection of measured altitude readings where the difference between the estimated output from the complementary filter and the measured altitude is greater than a threshold value, and wherein the controller is coupled to the thruster and configured to control the thruster motor in response to altitude and pressure information in order to adjust downward motor-thrust to neutralize upwardly directed buoyant force to maintain the user defined constant altitude above sea bed. a thruster and an altitude controller configured to control altitude, wherein a thrust of the thruster neutralizes upwardly directed buoyant force and the altitude controller is configured to maintain a user defined constant altitude above sea bed; an upward looking echo-sounder mounted on one of rear fins and used to measure surface wave profiles in a hover mode; a pressure sensor provided at an end-plate behind a nose-cone to operate in the hover mode; an acoustic modem mounted on another rear fin and used to communicate with a profiler from a surface craft; extra fins used to minimize rotation of the profiler about its own axis; a digital camera and a strobe light secured at the nose cone and diametrically opposite to each other; and a second echo-sounder mounted at a vertex of the nose cone and being connected to electronic circuits, wherein the altitude controller is coupled to the second echo-sounder for receiving altitude information, and coupled to the pressure sensor for receiving pressure information, characterised in that the altitude controller comprising: a Linear Quadratic Regulator configured to provide a low pass filter that rejects high frequency components; an integrator placed close to the thruster configured to remove biases in the pressure sensor and the thruster; and a second order complementary filter in a feedback loop, configured for complimenting altitude information from the echo-sounder with negative time derivative (-dz/dt) of depth measured from the pressure sensor for enabling the rejection of measured altitude readings where the difference between the estimated output from the complementary filter and the measured altitude is greater than a threshold value, and a Linear Quadratic Regulator configured to provide a low pass filter that rejects high frequency components; an integrator placed close to the thruster configured to remove biases in the pressure sensor and the thruster; and a second order complementary filter in a feedback loop, configured for complimenting altitude information from the echo-sounder with negative time derivative (-dz/dt) of depth measured from the pressure sensor for enabling the rejection of measured altitude readings where the difference between the estimated output from the complementary filter and the measured altitude is greater than a threshold value, and wherein the controller is coupled to the thruster and configured to control the thruster motor in response to altitude and pressure information in order to adjust downward motor-thrust to neutralize upwardly directed buoyant force to maintain the user defined constant altitude above sea bed.