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The state of the art 30 kHz EM 302 deep water multibeam sonar is manufactured by Kongsberg, Inc of Norway. The EM 302 transducers are modular linear arrays in a Mills cross configuration with separate units for transmit and receive. This sonar offers significantly larger swath width, increased data density and resolution. Beam focusing is applied both during reception and transmission. The system has up to 288 beams / 432 soundings per swath with pointing angles automatically adjusted according to achievable coverage or operator defined limits. In multi-ping mode, 2 swaths are generated per ping cycle, with up to 864 soundings. With multi-ping the transmit fan is duplicated and transmitted with a small difference in along track tilt. The applied tilt takes into account depth, coverage and vessel speed to give a constant sounding separation along track. The beam spacing can be adjusted as equi-distant or equi-angular. EM 302 uses both CW pulses and FM sweep pulses with pulse compression on reception, in order to increase the maximum useful swath width. The transmit fan is split in several individual sectors with independent active steering according to accomplish compensation for the vessel movements: yaw, pitch and roll. The high density, high resolution, large coverage and water column capability makes EM 302 an ideal system to explore the sea bed and the water column for detection and characterization of a broad spectrum of features.