The structure of the Processing Element (PE), which is the basic component of SMA1, is presented. The PE consists of a simple serial arithmetic unit, a local high speed data memory, serial input and output ports, serial communication channels with neighbouring PE's, and some local control logic. The PE array operates under the control of a microprogrammed Array Control Unit (ACU). The peculiarities of ACU microprogramming are discussed, and some typical microprograms are reported. After presentation of the SMA principal instructions, some application programs are described implementing common radar filtering algorithms.