Research And Realization Of Simulation Signal Source For Torpedo Acoustic Homing

Signal source is important for the development, test and maintenance of torpedo acoustic homing. It can help torpedo designer test performances of the acoustic homing system through emulating the characteristics of underwater targets and environment, and then exporting emulating data to the homing array in the form of multi-channel analog signal.This thesis detailedly discusses the operating principle, software and hardware design of the simulation signal source for torpedo acoustic homing, and its engineering realization. The paper focuses on signals synthesize algorithm and the control of multi-channel signal output beam. The main work in this paper is as following:Firstly, through analyzing the work principle, parameter estimation method and common signal types of torpedo acoustic homing system, combining the torpedo homing system hardware-in-the-loop simulation model, the function of the simulation signal source for torpedo homing are summarized. Then the theory foundation and mathematic model of the simulation signal source is established. The overall plan and structure is also put forward.Secondly, this paper analyzes signal synthesize algorithm and its characters, and researches the method of realizing determinate signals adopting DDS. The definition and characters of non-determinate signals (such as Gauss white noise, reverberation and narrowband noise) used in the simulation signal source for torpedo homing and synthesize algorithm are discussed. Time-delay algorithm and regulations for different receiving arrays are also developed considering the purpose of beamforming control.Thirdly, the author designes the simulation signal source system composed of multi-module, combining software management and procedure flow. The key parts in the simulation signal source design is developed, including the structure of pipelining array, signal processing algorithm, proper combination of pipelining array hardware resources, synchronization of the system, management of multi-processor and so on. On the base of system's hardware and software, the DSP realization of time-delay filtering algorithm is researched.At last, a simulation signal source test platform based on AR model and MUSIC algorithm is proposed. The frequency precision, phase delay precision, test method of space beamforming performance of the system's output are studied. Test result proves that the performances of this simulation signal source satisfy design requirements.