Signal processing 114 Digital techniques 49 Congresses 25 Integrated circuits 17 Very large scale integration 13 Image processing 7 Underwater acoustics 7 Data processing 6 Mathematics 6 Periodicals 6 Speech processing systems 6 Electro-acoustics 5 System analysis 5 Equipment and supplies 4 Adaptive signal processing 3 Computer architecture 3 Control theory 3 Design and construction 3 Digital filters (Mathematics) 3 Electronic circuits 3 Electronics 3 Mathematical models 3 Seismic prospecting 3 Stochastic processes 3 Adaptive control systems 2 Coding theory 2 Computer-aided design 2 Computers 2 Discrete-time systems 2 Electronic data processing 2