CONTENTS 



Page 



Sonar Target Classification Experiments with a Continuous -Transmission Doppler 



Sonar, by Frank J, Hester 1 



Introduction 1 



Fish echoes in relation to sonar detection 1 



Operating principles of a CTFM sonar for fishery work 2 



Controlling relationships 3 



Doppler system in block diagrann 3 



Target strengths of single fish 4 



School targets and their acoustic properties 5 



Feasibility study 6 



Lake Murray equipment tests 6 



Swimming pool tests 7 



Evaluation at Sea World 8 



Mission Bay Yacht Club pier 8 



Catalina tests 9 



Feasibility tests of methods of data evaluation and reduction 10 



The DELTIC spectrum analyzer H 



Kay vibralyzer and DELTIC 11 



U.S. Naval Ordnance Test Station 12 



Slow scan analysis technique 12 



3-D technique 13 



Conclusions from feasibility study 14 



Shipboard target classification experiments 14 



Equipment 14 



Methods 15 



Results of shipboard tests 17 



Reconnnnendations 18 



Sumn-iary 20 



Acknowledgnaents 20 



Literature cited 20 



Acoustic Target Strength of Several Species of Fish, by H. W. Volberg 21 



Introduction 21 



Facilities, equipment and methods 22 



Tests 23 



Fish without swim bladders 23 



Fish with swim bladders 24 



Relation of present to earlier findings 25 



Summary 26 



Acknowledgments 26 



Literature cited 26 



