CRR number 336 describes the results of tests run on the Simrad EK80 echosounder, which has recently replaced the EK60 model long used for fisheries surveys. To help the transition to the EK80, an international workshop was held in La Jolla, California in September 2016 whose participants included members of ICES Working Group on Fisheries Acoustics Science and Technology (WGFAST). The report documents the state of the technology as of this time, making suggestions necessary for the use of the EK80 in standardized surveys and thus for improving scientific information on living marine resources.
Results show that the EK60 and EK80, each transmitting single-frequency 'narrowband' pulses, provide equivalent measures. The EK80 can also transmit 'wideband' pulses spanning a large range of frequencies and apply matched-filter processing to potentially improve range resolution, signal-to-noise ratio (SNR), and target identification.
As well as quantifying these new features, workshop participants identified some practical limitations and made several recommendations. These included enabling channel-dependent logging ranges, faster and more programmable alternation between narrowband and wideband and between active and passive modes, and more user control over transmit signals and processing parameters.
Due to the increased potential and complexity of the EK80, additional workshops are needed to develop standard operating procedures for wideband calibrations, target strength estimations, and echo classifications.
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