PURPOSE: To offer a surface acoustic wave convolver displaying high convolution efficiency and with high yield in manufacturing and a communication system using the same.

CONSTITUTION: This convolver is the surface acoustic wave convolver with a feature that plural waveguides 4-1 to 4-n which propagate surface acoustic waves excited from electrodes 2, 3 for excitation in reverse directions with each other are formed in shape that the surface acoustic waves excited by the waveguides 4-1 to 4-n are formed as focusing beams and an electrode 5 for output which converts the surface acoustic waves generating at the waveguides 4-1 to 4-n and propagating the surface acoustic waves in a direction traversing the surface acoustic wave to electrical signals is provided at a position where it receives the focusing beam in the surface acoustic wave convolver provided with at least two electrodes 2, 3 for excitation which excite the surface acoustic wave on a piezoelectric substrate 1, the plural waveguides 4-1 to 4-n, and at least one electrode 5 for output.