With the mature of the national defense field,the importance of requirement generation is rapidly increasing.By demonstrating the top-level requirements,the effective traction for future development is achieved.As national defense acquisition is a typical complex system,which involves many processes and participates,it is necessary to propose an effective method based on system engineering theory,in order to guide the acquisition process and lead to a successful result.For implementing the requirement generation,the Joint Capability Integration and Development System (JCIDS) has been constructed.By defining a set of unambiguous and executable steps,the framework of requirement generation has been clarified,which transfers the defense acquisition from “threat-based” model to the “capability-based” model.Therefore,elaborating the requirement generation mechanism in defense acquisition is focused,especially for its compositions and operation process,in order to comprehend essentials of the defense acquisition and provide a reference for the related work.

As a typical representative of defense acquisition,equipment acquisition usually involves large amount of processes in execution.Meanwhile,due to the advancement requirements of the equipment,its realization must rely on the effective integration of advanced scientific and technological achievements in many fields.Therefore,the impacts of technological maturity and manufacturing maturity on acquisition programs must be considered.For ensuring the success of acquisitions and managing the implementation effectively,the department of defense has proposed defense acquisition system based on system engineering methodologies,which is one of the three decision support systems utilized in defense acquisition.By dividing the entire life cycle into several phases,an acquisition program goes through solution analysis,technical maturity,engineering and manufacturing development,production and deployment,operations and support,and retire processing phases,with the technological and manufacturing maturity improves simultaneously.By setting the milestone decision points between acquisition phases,the achievements of current phase and the goals of the subsequent phase can be evaluated.In this manner,the acquisition execution and phase transition can be supervised effectively and the program risk can be reduced significantly,which can finally realize the capability requirements described in joint capabilities integration and development system as an equipment.As a result,this work will focus on the defense acquisition system,to illustrate the acquisition phases and their corresponding tasks systematically,and finally provide a sufficient support for the related work.

With the development of the artificial intelligent technology,it has become the focus of many countries due to its impressive capabilities and great potential in the future.As a result,the artificial intelligent technology has been included in the national development strategy of many countries.Based on such technologies,various intelligent weapon systems have been developed,and some of them have been put into the practice.Therefore,the state of art of this area in foreign countries is summarized in this work,and the characteristics of diverse intelligent weapon systems are discussed as well.Finally,the future developing trends of the intelligent missile weapon system are concluded at the end.