The invention discloses a multilevel modulation ultrasonic encoding
single excitation method based on Golay complementary convolutional codes. The method includes the steps that a multi-element code C=A*B is generated for single encoding excitation by means of
convolution operation of an orthocomplementation Golay (A,B) code binary sequence;
amplitude modulation and
phase modulation of the multi-element code C are achieved through an encoding controller, code element symbols are mapped into electric pulse signals with certain phases and amplitudes, and an ultrasonic probe is excited; excitation
conversion factor conversion from C to A and from C to B is conducted on echo signals subjected to encoding excitation, two paths of echo signals are formed, the C code excited once indirectly generates the effect achieved by independent dual excitation of the A code and the B code, and the quasi
single excitation technology is formed; the two paths of echo signals are subjected to
pulse compression, and ideal encoding is achieved through vector synthesis; finally, complementary Golay (A,B) with the code length Lc being 8 is subjected to encoding excitation and decoding, the functions are simulated, and the encoding excitation effect is verified through FPGA hardware. Compared with a traditional method, echo
gain and excitation efficiency are indirectly improved, and the method also has great advantages in the aspects of
signal-to-
noise ratio, flexibility and implementation performance.