Design and implementation of logistics tracking and communication information system based on RFID

In logistics supply chain management, RFID tags can be used for material and product tracking throughout the supply chain process. From supplier supply to production, warehousing, distribution, transportation and sales. Production enterprises are required to ensure orderly and correct production processes in manufacturing units (such as workshops); in warehousing units, raw materials and products (semi-finished products and finished products) are required to be accurately classified and placed. In order to ensure product quality, raw materials and semi-finished products must be processed, packaged, labeled, placed and Stored in the warehouse, and go through the manufacturing process in the workshop to produce finished products and then return to the warehouse. In each process, labels are required to be attached to the production and storage units of materials to avoid errors due to loss of product information. Therefore, it is necessary to use modern positioning and communication technologies to establish a full-time, full-airspace, and all-weather logistics tracking and communication information system (Logistics tracking and communications information systems, referred to as LTCIS) that meets the requirements and development of modern logistics supply chains.

2 Logistics tracking information system LTIS (1logisticstrackinginformationsystems)

LTIS is used to track and record the circulation information of materials (raw materials and products), warehousing and transportation in logistics units such as product planning, workshop production, warehouse management, loading and unloading, and long-distance transportation.

2.1 Architecture of LTlS

RFID can identify and track specific materials, and can realize the correlation and synchronization of logistics and information flow. To track labels and the objects they are attached to, it is necessary to record the material's circulation history. LTIS uses the tag's remaining memory to store and update tracking information in real time that cannot be contained in a 64-, 96- or 256-bit Electronic Product Code (EPC). Three important tables are designed for this purpose, namely tables for labels, logistics tracking, and historical operations. These tables record the circulation history and current status of materials. LTIS hardware consists of tags, fixed readers, portable readers, Library-borrowing-machine-touch-query-intelligent-terminal-all-in-one-machine.html target='_blank'>workstations distributed in different places, a series of fixed application servers, RFID middleware servers, web servers and database servers, Wi-Fi LAN, and GPS terminals. Figure 1 shows the architecture of the LTIS solution.

In order to balance the workload, make network updates and maintenance more convenient, and comply with the intranet and database standards of existing logistics enterprises, the LTIS software adopts a distributed 3-level client/server architecture system. Also consider browser/server architecture as an additional solution.

LTIS software includes 6 functional units: raw material and semi-finished product processing subsystem; warehouse monitoring subsystem; material tracking subsystem; system management subsystem; material unit and logistics unit Wi-Fi positioning subsystem; logistics transportation unit GPS positioning and navigation system.

2.2 LTIS of Wi-Fi/GPS/RFID solution

Because the logistics operation space is very vast, or like a logistics transportation unit, it is far away from the base and the working environment is closed, which creates application obstacles for most traditional RFID solutions. Developing an infrastructure of RFID Readers that can provide the location of goods and equipment in real time is too expensive and requires antennas to be installed in the work area. To this end, this article designs LTIS for Wi-Fi/GPS/RFID solutions. This system is similar to AeroScoutu's newly launched UnifiedAssetVisibility (UAV) solution. The Wi-Fi/GPS/RFID solution can locate the location of material units and logistics units in a wide area, and can meet positioning requirements even in remote areas where Wi-Fi access points are sparsely distributed.

LTIS’s Wi-Fi/GPS/RFID solution provides a solution by combining GPS and Wi-Fi active RFID tags. The software allows users to locate tagged items based on the strength of tag signals received by multiple standard 802.11 Wi-Fi access points, which also serve as RFID readers. When the tag is too far away and its signal cannot be received by at least three Wi-Fi access points, the GPS receiver embedded in the tag can determine its longitude and latitude, and then send data through the Wi-Fi signal.

When working in GPS or Wi-Fi mode, tags can be located within 510in. However, GPS does not work in all environments. Some logistics units are closed and cannot receive satellite launches. Each logistics unit requires a certain number of Wi-Fi access points. The network can receive signals from tags anywhere in the logistics unit.

Label the positioning target. The tag needs to contain Wi-Fi and RFID chips, antennas, GPS chips, motion sensors and batteries.

When receiving a job task, the employee determines what Tools are needed to complete the task and enters the name of the device on the LTIS software independent system of the Wi-Fi/GPS/RFID solution. The software then displays a floor plan of the logistics unit, with icons indicating the location of items. The system can also search for all devices by selected categories.

The tag sends ID code and GPS data at set intervals. Because the tags have motion sensors embedded in them, when the device is stationary, the signal is sent at a lower frequency than when it is moving.

The final plan is to integrate the Wi-Fi/GPS/RFID system into existing inventory management and extend it to all logistics units to be applied to larger logistics sites, such as airports and ports.

2.3 Design and implementation of LTIS

In LTIS, applications communicate directly with hardware devices. Wi-Fi/GPS/RFID systems include devices, applications and RFID middleware. In order to ensure the stability of the system, another application is designed to connect the RFID reader and writer with the client application as a backup solution if the RFID middleware server fails. But it needs to call the local dynamic link library.

(1) Communication between application and RFID reader. There are four types of RFID devices due to different operating frequencies. In logistics enterprises with various types of materials and complex working environments, taking into account the processing speed and the allowable range of the spectrum, flexible selection is required according to the requirements of logistics operations. In the logistics unit, choose a fixed RFID reader module, such as the $6500 long-range reader module from Texas Instruments (TI), which can meet all RF and digital functional requirements and can be used with Tag-itHF from various suppliers. , Tag-itTMHF-I (International Organization for Standardization 15693 standard) communicates with all other ISO15693 standards.

This article uses two methods to communicate with the reader. One is that the application software with the $6500 reader on the client computer communicates by connecting to the local dynamic link library.

The other is to install an RFID middleware that connects the reader and the client application. The above dynamic link library Files (fecom.dll and feisc.du) are written using Microsoft basic classes. Use Java, use the method of calling the local link library, use Visual C++ and design middleware according to the Java Native Interface (JNI) standard. RFID middleware is based on three parts: reading interface component, event management component, and application management component. The structure is shown in Figure 3.

The application of RFID reader needs to go through the RFID middleware server, which can support distributed network applications. It makes heterogeneous RFID readers from different vendors compatible and makes applications independent of specific hardware and locale. Portable RFID readers can read and consult the information stored on the tags. Portable RFID devices are composed of RFID reader modules and smart terminals. They are connected via RS232 or other interfaces.

(2) Implementation of Wi-Fi/GPS/RFID

① RFID smart equipment includes 3 parts: RFID data information collection unit; data carrying unit; information transmission unit.

Through these three units, RFID smart devices are integrated on smart terminals. The platforms that can be selected include WindowsMobile, WindowsPocketPC (windowsCE), AndroidOS, and LinuxOS. The smart device will complete data collection and real-time update according to the data instructions provided by the system management center. The data unit structure is shown in Figure 5.

The lowest level is the operating system and hardware configuration. You can choose WindowsMobile, CE, Linux, Android and symbian systems. Hardware suppliers that can be selected include: TI, Qualcomm, Freescale, Samsung, MTK, Broad-com, MarvelandIntel.

At present, these smart terminal devices are easy to find in the market. You only need to develop the standard C and C++ source code in the system or the RFID usage kit and interface for these hardware devices.

Data carrying units include mainstream communication units currently used in the domestic market, including GSM, WCDMA, CDMA, TD technology, and Wifi technology. These technologies can provide a real-time data exchange environment for intelligent terminal devices, and can call the corresponding data communication unit when needed.

The RFID unit is responsible for identifying relevant information of hardware devices. The smart terminal is responsible for maintaining the collection and processing of RFID information at its location. Due to the intervention of the operating system, the data terminal is responsible for the coordination and reporting of all tasks.

②Example. Each piece of cargo has an RFID tag; the smart device is responsible for collecting cargo information in the current area and providing statistics and reporting functions. General logistics personnel can understand the status of the cargo (under logistics conditions, smart devices need to be placed on the logistics vehicle); on the vehicle There are 200 pieces of goods, and the intelligent terminal device can read the data and update the data to the headquarters server in real time according to the instructions of the system.

2.4 Basic functions that smart devices can complete

(1) Inquiry service. On the network platform provided by the company, ordinary customers can query functions, including logistics status (traditional information such as delivery and logistics starting location).

(2) Tracking function. Among them, for fixed partner customers or large customers, adding GPS location information reporting can allow customers to know the location of goods at any time. (When the system issues an instruction, the smart device will transmit the RFID information, Wifi, and GPS positioning information to the company platform.)

(3) Regular reporting function. The device can activate SMS reminder and email reminder functions in real time when the goods arrive at the designated GPS information point or fixed wifi area according to the system's pre-set settings. Deliver booking information to customers who made reservations in real time.

(4) Expand functions. The device can integrate with the current logistics company's system platform and extend the user terminal interface to smart devices (similar to laptop functions). Operators can manage and update the company's logistics data through permissions.

Expanded functions include: For professional customers, we provide high-level development of smart terminals, including data collection, data update, traffic services, video services, etc.

3. Logistics tracking and communication information system LTCIS

Wi-Fi, GPRS, INMARSAT, and Internet are all technologically mature communication information systems with independent communication standards and network structures. It plays an independent but complementary role in the information transmission and data exchange between the logistics transportation unit and other logistics units in the supply chain, especially with the central control information center. Through mutual coupling and networking, a reliable and practical logistics communication information system (LCIS) is established, which becomes the antenna and information highway connecting the material tracking information system, logistics tracking and positioning navigation system and central control system. LTIS (Wi-Fi/RFID/GPS), LCIS (Wi-Fi/GPRS/INMARSAT), and MIS (Management In,formation System) realize networking through the coupling of communication standards and establish LT-CIS, which is technically There are no obstacles.

  4 Conclusion

This article proposes a solution for a logistics tracking information system that integrates RFID, GPS and Wi-Fi. Based on this and combined with the latest communication technology, an all-weather, all-time and space-time LTCIS network was conceived. It is a good inspiration and attempt for the connection, smoothness and global management of the supply chain of logistics enterprises.