Wireless Communication Technology Features and Development Trends

With the development of science and technology, wireless communication technology has developed rapidly. However, there have been a series of problems in the development of wireless communication technology, and many technical obstacles have been encountered. At present, China is gradually entering the 3G era, wireless communication. Technology has developed rapidly in our country. This article analyzes the respective characteristics of wireless communication technology and discusses the development trend of wireless communication technology.

1.1 WLAN Technology Analysis The Wi-Fi technology and products are quite mature and are produced in large quantities. This technology is applicable to wireless LANs. As an extension of wired networks, Wi-Fi technology is still widely used in security applications for broadband applications in special locations. However, Wi-Fi uses radio frequency (RF). ) Technology that sends and receives data through the air. Because wireless networks use radio waves to transmit data signals, they are vulnerable to attacks from the outside world. Hackers can easily steal data within the coverage of radio waves and even enter unprotected intranets.

1.2 WiMax Technical Analysis WiMax is an advanced technology. It is relatively late to launch, and it has the problem of low frequency reusability and low utilization rate. However, due to the recent completion of standardization, the large-scale promotion of this technology requires a practical test. From the application perspective, the technology can meet the Internet access requirements in a wide range. Coverage can include outdoor and indoor, and it can cover large areas of signals. Even a few base stations can achieve citywide coverage. Due to its advanced technology and ultra-long transmission distance, WiMax has always been favored by the industry. It is the development direction of future mobile technologies and provides excellent last-kilometer network access services.

L.3 WMN Technical Analysis WMN is a technology under study. It constantly integrates various aspects of technology in different aspects, and there is no mature product series to support the large-scale application of the technology. From the application perspective, the emerging WMN network not only has a broad application space in wireless broadband access. In other aspects such as combining data, image acquisition module can monitor the target object or data acquisition, and is widely used in environmental detection, Industry, transportation and other fields.

1.4 3G Technical Analysis 3G put forward standards in 1996 and completed the establishment of complete standards including the upper level agreements in 2000. 3G network deployment already has considerable practical experience, and there is a set of theory of network construction, including the link budget of the network, propagation model budget, and computer simulation. From the commercial perspective, at present, 3G has been applied to large-scale commercial applications in some regions. For example, many countries in Europe, Japan, and South Korea have already established 3G networks. 3G technology has entered a practical stage, and many countries and regions are building or will build 3G networks.

1.5 LMDS Technical Analysis The local multi-point distribution service system LMDS is a fixed broadband wireless access technology providing point-to-multipoint communication. Its operating frequency is above 20 GHz, and it can provide digital duplex within a certain range by using millimeter wave transmission. Voice, data, Internet and video services are a very good broadband fixed wireless access solution. In the best case, the distance is up to 8 km; however, due to the rainfall, the distance is usually limited to 1.5 km.

1.6 MMDS Technical Analysis The main disadvantage of MMDS is that it has blocking problems and the signal quality is easily affected by weather changes. The available frequency band is also not wide enough and it does not exceed 200 MHz at most. Second, MMDS requires very strict transmission paths. Because the modulation technology used by MMDS is mainly phase-shift keying PsK (including BPSK, DQP-SK, QPSK, etc.) and quadrature amplitude modulation QAM modulation technology, non-line-of-sight transmission cannot be achieved, and it is difficult to promote in the current complex urban environment. application. In addition, there is no uniform international standard for MMDS, and there are compatibility issues among the manufacturers' equipment.

1.7 Cluster Communication Technology Analysis The digital trunking system has many advantages, and its spectrum utilization rate is greatly improved, which can further improve the user capacity of the trunking system. It improves the ability of the signal to resist channel fading and makes the radio transmission quality better. With the development of mature digital encryption theory and practical technologies, confidentiality is greatly improved for digital systems.

1.8 Point-to-point Microwave Communication Technology Analysis The advantages of microwave transmission are mainly reflected in the following aspects: First, the operator's operating costs can be reduced. Compared with leased lines, the investment in microwave systems can be recovered in as little as one year. Second, the microwave transmission system is simple and fast to deploy. Compared with traditional transmission methods, the advantages of rapid deployment can meet the needs of new business development more quickly. Third, the current microwave products are guaranteed for the future development and can provide good support for operators' new services and new demands. In the future, the microwave transmission system will be upgraded to an all-IP platform, which will fully support the future development of operators.

1.9 Analysis of satellite communication technology Satellites are used in land communications in some areas where the population is not very dense. In these areas, there is a wide range of users who are not dense, and satellites can be used as the access facilities for users to connect to fixed wired networks. In the environment where the land-based communication network has formed a broadband multimedia communication network, the use of satellites to build a broadband satellite access system is a relatively good and practical solution, which is economical and reliable.

However, satellite communication is after all using satellites as a communication platform. The construction of ground stations and the rental costs of communication channels require large amounts of money. The communication resources are owned by satellite communication companies. Due to the limitation of its bandwidth, the transmission of large amounts of data needs to be very expensive. Big price. Therefore, it is extremely uneconomical to use 13 as a normal production and daily life, and it is appropriate to use satellite communication as emergency communication, combat communication, and overseas communication.

2. Trends in the development of wireless communication technology The complementarity of various technologies in the field of wireless communications13 has become clear. This is mainly manifested in different access technologies with different coverage, different applicable areas, different technical characteristics, and different access rates. For example, 3G and WLAN, UWB, etc., can achieve complementary effects. 3G can solve the mobility requirements of wide-area seamless coverage and strong roaming, WLAN can solve the high-speed data access in the middle distance, and UWB can realize ultra-high-speed wireless access at close range.

2.1 Broadband Broadband is one of the important directions for the development of communications and information technology. With the further development of fiber-optic transmission technologies and high-permeability network nodes, the broadband network is being fully deployed worldwide, and wireless communication technology is also evolving towards the broadband access of wireless networks, and the wireless transmission rate will be The second-generation system's 9.6 Kbit/s has evolved to the highest rate of 3 Mbit/s for third-generation mobile communications systems.

2.2 Integration of Core Networks and Diversification of Access Networks The future structural model of information networks will shift towards core networks and access networks, and packetization and broadband of networks will make it possible to comprehensively transmit multiple service information on the same core network. The integration of networks and the gradual opening of regulations and the need for market competition will further promote the integration of traditional telecommunications networks with emerging computer networks.

2.3 Personalization of information Personalization is one of the main directions for the further development of the information industry at the beginning of the next century. Mobile IP is an important technology for personalizing future information. Implementing various IP applications and mobile IP technologies on mobile phones is gradually becoming one of the focuses of attention. The combination of mobile intelligent network technology and IP technology will further promote the trend of global personal communications.

2.4 The mobile communications network structure is undergoing a profound transformation With the formation of a dominant position in the data traffic in the network, the transition from the existing circuit-switched network to the IP network has become irresistible, and IP technology will become the core key technology of the future network. The IP protocol will become the dominant communication protocol of the telecommunications network. With the introduction of the General Packet Radio Service (GPRS) for mobile communications, users will send and receive data in an end-to-end packet transmission mode, breaking the traditional data access mode. IP-based networking has started the practice of mobile backbone IP applications. 3 Conclusions The contradiction between the bandwidth demand of wireless communication networks and the shortage of mobile network bandwidth, the contradiction between the geographical distribution of users and the imbalance of application requirements, and the coexistence of different technical advantages and disadvantages, therefore, it has been decided that the development of wireless communication networks needs to be comprehensively applied. From the perspective of the overall situation and long-term perspective, this kind of technical means adopts an integrated approach to planning and building a network. The use of different technologies in terms of individuality and comprehensive layout to address the different needs of different regions and different user groups for bandwidth and services has achieved the overall advantages and comprehensive capabilities of wireless communication networks. In short, the future development trend of wireless communications in the mid-term is: complementary development of various wireless technologies.