H. R. Baker 127 
necessary to accumulate data on sound propagation through the shallow waters 
of strategic locations. These data can best be obtained by a cooperative effort 
of the nations bordering the waters ofthese strategic areas. Some fixed installa- 
tions for research purposes are highly desirable. It is entirely possible that 
information gained from relatively modest fixed installations may serve to guide 
the development of operational installations. 
There are several locations near islands where deep-water sound stations 
could be installed and cabled to shore. From these stations, continuous data 
on reverberation and noise levels could be recorded. In cooperation with a sub- 
marine equipped to transmit and receive, transmission loss could be measured 
over a great range in any kind of weather. 
Propagation data for the cold water of the North Atlantic, the Norwegian Sea, 
and the Arctic Basin are meager. While the severe climate would increase the 
difficulty, fixed stations in these strategic areas could be established; and the 
data are badly needed. 
7.3. SIGNAL PROCESSING 
Fixed sonar stations can be used for experimental signal processing with 
little additional equipment. Such matters as signal coherence in time and space 
can be analyzed on a statistical basis. By careful attention to recording pro- 
cedures, data can be preserved and distributed on magnetic tape to the various 
laboratories, where it can be used many times and with different signal proc- 
essing equipment. Ideas for new research in the area of signal processing will 
be covered in another paper. 
7.4. COUNTERMEASURES 
A submarine is blind when denied the use of the surface of the ocean and 
depends upon its ears for information. Little efforthas been exerted in research 
and development to find effective means to deceive submarines. While acoustic 
countermeasures in themselves cannot destroy submarines, under the right 
conditions they can be used effectively to lure them to areas susceptible to 
attack or to keep them away from convoys or naval task forces. Acoustic tor- 
pedoes can likewise be deceived and directed away from their intended victims 
by well-designed countermeasures. Carefully planned work on acoustic counter- 
measures in peacetime could be of great value in time of war. 
I have deliberately pointed out areas where international cooperation is 
desirable in the research and development program. The Division for Scientific 
Affairs in NATO attempts to stimulate interest and sponsor research in areas 
where the efforts of morethanone nationare required for achieving best results. 
