基于复合混沌映射的基阵式水下成像编码信号设计

he transmit-receive scheme which used a transmitting array to simultaneously transmit orthogonal signals while receiving array was adopted to receive echo signals had been primarily used to solve the problems of low frame rate and poor real-time ability shown in array-based underwater imaging systems, caused by low frequency of acoustic sensor, narrow bandwidth and many array elements to be used in transmitting arrays. The scheme required that the transmit signals were orthogonal to separate the signal channels, However, it was difficult to obtain a large number of orthogonal signals with common orthogonal optimization methods. A new optimization method for coded orthogonal signals of array-type underwater imaging based on compound chaotic map was proposed, It made use of the pseudo-random sequence generated by the multistage chaotic system with variable parameters to modulate the signal. The simulation test shows that this method can overcome the limitations of many factors such as the number of signals transmitted, coding length, array elements and so on, it also has the advantages of strong anti-interference performance and bandwidth increase, and it can realize the optimization design of the signals transmitted by any underwater arrays.