Abstract: Agricultural Internet of Things (AIoT) is the highly integrated information technology such as computer, internet and mobile communication’s application in agricultural field, and it is the essential condition for the agricultural informatization and intelligent. With the development of AIoT industry, there appears an endless stream of AIoT application systems, because of the lack of analysis for AIoT system’s whole architecture, the current AIoT application presents the fractional, vertical and heterogeneous characteristics. Extracting the system components and their relationship from various AIoT applications, and establishing AIoT system architecture, to achieve the AIoT’s design and realization method’s unification are urgent problems need to be solved. The paper analyzed the AIoT’s concepts, basic features and system structure research status, and found that the IoT development and management plans from different countries and institutes played good guidance for the related researchers, however, they didn’t give the specific methods that can design and realize the IoT systems, and furthermore agricultural environment’s diversity and complexity determine that AIoT architecture’s establishment must consider agricultural industries characteristics as a whole. Therefore, the paper firstly discussed the agricultural architecture building principles including extensibility, reusability, safety and reliability and so on, then combined with the specific needs of agricultural industry and experiences from engineering practices, put forward an AIoT hierarchical structure model, the model is divided into five layers from the bottom to the up, they are perception layer, access layer, network layer, data layer and application layer, respectively, and each layer corresponds to different communication protocols. And pointed out that AIOT hierarchical model and the corresponding protocol architecture constitute the AIoT architecture. Compared with the traditional three layers and four layers architecture, the proposed architecture added the access layer and data layer. Aiming at the problem that the majority objects in the ubiquitous environment have limited resources and computing power, the access layer emphasized that the underlying heterogeneous sensor networks can connect to the network layer seamlessly, it provides a unified abstract management interface to shield the complexity of the underlying heterogeneous sensor networks, and reduces the difficulty of building AIOT perception system. For the problem of agricultural data can not be fully used in current AIoT systems, and formed the information islands, the data layer designed and realized a service oriented architecture to solve the data exchange and sharing problems among different AIoT systems. Overall the five layers architecture’s functionalities are more independent, it is advantageous to the network load balancing between each layer, and reducing the burden of enterprise network communications. Aiming at the common problems of the application of agricultural industries, according to the different objects to be monitored, analyzed the agricultural production environment monitoring IoT, plant and animal life information monitoring IoT, agricultural products quality detection and the quality safety tracing IoT, agricultural machinery operation monitoring IoT’s present research situation and main technologies involved. From the perspective of agricultural application architecture, it was found that the current researches are more concentrated on the gateway hardware, and the embedded gateway middleware application is relatively few on the one hand, on the other hand the AIOT data sharing layer’s research is seriously lacking, each application system usually sent the perceive data directly to the AIOT application layer, therefore it is difficult to achieve the effect of further guiding to agricultural production for the lack of data mining and analysis. Finally, the paper discussed the further research and application direction of the AIoT technology.

Key words: agricultural internet of things, system structure, architecture model, application area, development direction