introduction

With the rapid rise of mobile Internet data, wireless application services and Internet of Things technologies, mobile phones are increasingly becoming a must-have tool in people's daily lives. Now, mobile phones can not only be used to make calls, but also to achieve more daily life services.
   In the near future, mobile phones will replace many cards on modern people, such as credit cards, loyalty cards, transportation cards, etc., which can help people complete services such as purchasing tickets, paying bills, and shopping for points. Not only that, mobile phones can also exchange images and download music, and even mobile terminals can download entertainment information by reading smart posters [1]. These features are not only attractive to consumers, but will also greatly expand the application and sales market for mobile phones.

The birth and application of NFC, a near field communication technology, will make this possible [2].
   However, the current NFC technology can only support wireless services with data rates of several hundred kb/s, which greatly limits the application of video images, and also becomes a bottleneck for the promotion of NFC technology.

1 NFC technical characteristics

As a short-range wireless communication technology, NFC combines the use of Radio Frequency Identification (RFID) and wireless connection technology, using the 13.56MHz band [3]. Although the communication distance is only about 10cm, like the contactless smart card (IC) card technology, "just touch", you can exchange data between different electronic products [4]. Due to the limited communication distance of NFC technology and the single point-to-point connection that limits the possibility of interception, the main advantage of NFC is its high level of security. In addition, NFC technology supports advanced encryption, which makes NFC-based systems more suitable for businesses such as finance that involve secure transactions.

Unlike a contactless IC card, NFC can communicate in both directions. As long as it is an NFC-enabled product and an IC card, data can be read or written, and communication can be performed between portable products such as mobile phones. The data transmission speed is not high, and there are four speeds of 106kbit/s, 212kbit/s, 424kbit/s and 848kbit/s, which can be increased to about 1Mb in the future.

2 Large-capacity information push technology based on near field communication

Intelligent information push is a brand-new network-based information publishing and business promotion platform. Like other network information publishing platforms, it can be used for information release and business promotion. It can actively push customized business information, important notices, etc. to specific user groups; it can analyze user behaviors and understand user consumption habits; network operators can use it to notify users of the usage status of package charges in a timely manner, and call for arrears; Transparent consumption, improve users' network experience and improve user satisfaction.

The NFC-based large-capacity information push scheme is based on NFC and broadband mobile communication technologies to realize the interaction and push of information between users and systems. The system is mainly composed of mobile terminals, intelligent information terminals and system platforms. Figure 1 shows.

Research on large-capacity information push technology based on NFC
2.1 Mobile terminal

The mobile terminal refers to a user handheld communication device with an NFC function, and has functions of acquiring targeted push information (such as coupons, product information of advertisements, etc.) and actively querying information. The NFC terminal technology mainly involves hardware structures such as NFC chips, antennas, and card readers. Based on the current technical implementation schemes, that is, according to the relationship between the NFC chip (CLF) and the security unit (SE), the NFC terminal implementation method mainly has three Kinds: Full terminal mode, based on SD card (Secure Digital Memory Card) and SIM (Subscriber Identity Module) based. The all-terminal mode mainly refers to the integration of a non-contact communication module, a security module (SE), and an antenna in the terminal.

There are units. Since the SE is more likely to be cracked in the all-terminal mode, the full-terminal method is not suitable for financial services involving personal information security. The SD-based solution simulates the SD card of the smart terminal into a SE security module with high security, and stores important information such as user information on the SD card. Because the SD-based method monopolizes the storage interface and separates the communication function from the smart card, it brings troubles for subsequent application management and storage management. There are still many problems in the future application of the mobile Internet. It can be seen that the SIM card-based solution with both security and flexibility is the implementation of the NFC function commonly used in the world, as shown in Figure 2.

2.2 Intelligent Information Terminal

The intelligent information terminal is mainly for the information push terminal device deployed outdoors, and can complete the cyclic display and regular update of the advertisement information, and can realize the function of pushing the information required by the user to the user through the NFC function. The NFC technology is used between the intelligent information terminal and the mobile terminal to realize a fast and convenient wireless connection with high security. The intelligent information terminal is composed of a main control module and an NFC module, and its architecture diagram is shown in FIG. The main control module is mainly responsible for the functions of management, operation, storage of information, and information interaction with the service platform of the intelligent information terminal. Therefore, the module usually installs ARM (Advanced RISC Machines) chip of Linux system, and can write video decoding and playing module, which has strong portability. The NFC module is an NFC-enabled card reader or development board that is responsible for real-time communication with NFC-enabled mobile terminals.

Research on large-capacity information push technology based on NFC

2.3 System Business Platform

The system business platform is mainly for the business management platform and the simple business support platform. The system service platform and the mobile terminal realize high-speed wireless connection through a broadband mobile communication system such as a third generation mobile communication system (3Generation, 3G) and a fourth generation mobile communication system (Long Time Evolution Advanced, LTE-A). According to the deployment characteristics of the intelligent information terminal, the system service platform can establish a connection through a wired link or a wireless local area network (WLAN). The system business platform mainly includes the following functions.

1) User information management. Manage user's opening and unsubscribing, record user's detailed information and use log habits, etc., to facilitate unified management of user related information. 2) Advertising management. Manage smart terminal playback content and tag information. The tag information may include text, pictures, and multimedia. The text information is directly transmitted through NFC, and the picture and multimedia only transmit the URL of the picture and the multimedia, and the mobile terminal acquires the file through the web. 3) Query management. When the mobile terminal sends the query request information to the smart information terminal, the system service platform first verifies the user identity, and if the verification fails, the connection is interrupted, otherwise the smart information terminal will be set to the card reading mode. The mobile terminal queries the information through the web according to the query result, and displays the query result. 4) Key management. The administrator periodically updates the keys of the mobile terminal and the intelligent information terminal to enhance the security of the user identity certificate.

2.4 NFC-based large-capacity information push process

The NFC-based large-capacity information push solution utilizes the advantages of high-speed data transmission of NFC technology short, frequency, fast and broadband mobile communication systems through NFC and broadband mobile communication convergence systems to achieve high-speed, high-security information interaction, and its signaling The process is shown in Figure 3.

Research on large-capacity information push technology based on NFC

Figure 3 Flow chart of large-capacity information push signaling based on NFC

When the user of the handheld mobile terminal sees the information of interest on the intelligent information terminal, the mobile communication terminal on the user side sends an NFC link request by uploading an NDEF (NFC Data Exchange Format) message or scanning the NFC tag of the intelligent information terminal. Interaction provides an easier way to send data than other wireless technologies (such as Bluetooth) because NFC does not require manual device discovery or pairing requirements, and the two devices automatically connect when they are close to a certain range; then the smart information terminal moves through the read The identity certificate in the terminal SE module identifies whether the mobile terminal has an authorization certificate for establishing an NFC link; after the mobile terminal passes the identity authentication, the mobile terminal NDEF data is appropriately classified, and an application interested in the data is started, and the application is declared. An intent filter and request a corresponding mobile internet service; the smart information terminal operating in the "reader" mode does not transmit the service information through the NFC link after acquiring the user's request information, and the system service platform is Send a URL message query request; the system service platform receives the query request After the information query, the queried URL message is sent to the mobile terminal through the intelligent information terminal; the mobile terminal that obtains the URL message can log in to the system service platform by using a channel, a multimedia message, and a data transmission provided by the broadband mobile communication system to realize high data. The rate of mobile internet application downloads.

3 Business applications

The NFC terminal using the NFC-based large-capacity information push scheme can not only simulate cards, but also realize high-speed, high-security data transmission. For example, in the audio-visual product store, as shown in FIG. 4, the user can quickly read the NFC tag on the smart poster through the NFC link to obtain an advertisement profile of a large number of audio-visual products. If the user wants to know more about the specific content of an audio-visual product, the NDEF message can be sent through the NFC link to obtain the URL message of the partial segment of the audio-visual product, and the audio-visual product can be downloaded or browsed through the broadband mobile communication link established by the mobile terminal and the system service platform. Part of the fragment, quickly understand the content of the corresponding product; if the mobile user wants to buy this product, simply convert the mobile terminal to the card simulation work mode, you can realize the one-stop self-service shopping experience of search, preview and payment.

Research on large-capacity information push technology based on NFC

Figure 4 NFC-based large-capacity information push scheme

4 Conclusion

This paper proposes a large-capacity information push scheme based on the combination of short-range communication technology and broadband public mobile communication system. From a technical point of view, the solution combines 13.56MHz short-range communication technology and broadband mobile communication technology, featuring short, fast, fast, high security and high-speed data transmission. Compared with the transmission rate of traditional short-distance communication technology of several hundred Kbit/s, the maximum transmission rate of this scheme is equivalent to that of broadband mobile communication system, which greatly improves the mobile data transmission rate; on the other hand, with a single broadband mobile communication system. Compared to security and convenience, it has also been significantly improved. Therefore, the solution is particularly suitable for providing solutions for mobile Internet services such as videos and pictures related to financial information and identity information.