Datang's 3.5GHz wireless access system for sustainable operation

Operators generally according to the requirements of the city network construction and market users gradually increase the trend, and strive to build a high-speed, high-capacity, broadband, high reliability of the sustainable development of broadband access network. 3.5GHz The successful implementation enables operators to quickly occupy the market, develop customers, provide users with a wide range of broadband access services, and can support voice, data, images, Internet and other multimedia and various value-added services, in the IP service, data access and voice Access market competition in the leading position.

As a continuous operation of 3.5G broadband fixed wireless access system for operators, we should consider all kinds of factors synthetically:

* Support a variety of business access, business interface is rich and in line with international standards, and existing network equipment can be interconnected and interoperable.

* With high spectral efficiency, it supports multi cell cellular network, multi sector base station and sector frequency reuse in metropolitan area.

* Meet the needs of business development, continuous upgrading and smooth expansion capacity.

* The price is reasonable.

Datang Telecom Technology Co., Ltd. by virtue of industry-leading technical strength, as well as a wealth of practical engineering experience in 2001 in Nanjing, Xiamen, Wuhan, Chongqing, the first batch of 4 pilot cities 3.5GHz Broadband Wireless access commercial system construction. After more than a year of operation, the system has accumulated quite a lot of actual operating experience. Datang Telecom in Shanghai, Guangzhou, Dalian, Nanning, Ningbo, Guiyang, Kunming, Changsha, Hohhot and other fields have carried out some experiments, try to operate in different operating environment system application solutions.

Datang Telecom R2000 Airsun system adopts multi sector coverage, multi carrier TDMA technology, 64QAM modulation technology, 2/3 convolutional coding plus forward error correction, ATPC technology and digital roll down filtering technology. With its high spectral efficiency, the best resistance to the same frequency/neighbor-frequency interference, rich business interface, support for multiple services, powerful dynamic bandwidth capabilities and QoS assurance, by the operators of the high praise, in the 3.5GHz Broadband wireless access system in the telecommunications level of application in the field of performance is the leading domestic.

Multi-business support capabilities

As a telecommunications operator providing integrated services, requirements 3.5 GHz Broadband Wireless access system must have a multi-service support capabilities, in the provision of connection-oriented voice and digital circuit hosting business, but also provide connectionless business (including IP voice, IP video, Internet access, LAN interconnection, virtual private network VPN, etc. To address the need for backbone and metropolitan area Network access, and to expand potential future business, such as WLAN, 3G and so on.

Datang Telecom R2000 Airsun Base Station can provide e1/g.703, V.35/X.21/FR, 10/100baset, V5.2 interface. The remote station can provide e1/g.703, v.35/x.21, 10/100baset, Qbri and pots interfaces. Support PSTN voice and IP telephony, video services and a variety of IP data Services applications, can also be used for mobile communication base station links.

Datang Telecom 3.5GHz Fixed Wireless access system base station frame on the backbone of the main pop node, flexible use of network backbone pop node provided by the nxE1, 10/100baset connection interface, so that the telecommunications operators can quickly and flexibly to provide integrated service access to end users.

The data transmission business can realize nx64k and 2Mbps real-time circuit business, data special line (FR, ATM, DDN) business. IP business can realize the Internet access of group users,

IP Voice, LAN interconnection, virtual private network VPN business, conference television business. The system has the powerful dynamic bandwidth allocation ability and the telecommunication level QoS guarantee.

Protect the spectrum efficiency of profit

Datang Telecom R2000 Airsun Point-to-Point Broadband wireless access system base station using sector, each sector can be configured up to 8 carrier. Each base station can have 24 sectors of the network capacity, in the multi-sector coverage by the frequency multiplexing method to cover, adjacent sectors using different frequencies, when a typical 8 sectors of a base station coverage, frequency multiplexing rate is 4. The single base station collection bandwidth can reach up to 384E1, and the remote station net rate can reach 2E1. Coverage radius of 10 km, using a high gain antenna, the coverage radius can also be extended.

Frequency multiplexing is an important index to determine the efficiency of the spectrum, which refers to the frequency of the same RF frequency group which can be used in other sectors or honeycomb in order to obtain more capacity from the limited frequency band. The frequency multiplexing coefficient is determined by the c/i value of the system and the characteristics of the antenna. The signal-to-noise ratio of R2000 Airsun is 21dB (ber=10-9), and the signal-to-noise ratio is -15db (ber=10-9), and its -3db bandwidth is only 1.1MHz, with the roll drop faster, with a good rectangular coefficient, which makes the R2000 Airsun adjacent sectors can use adjacent frequencies.

Frequency planning and network capacity are determined by the spectrum width that operators can use. In the second 3.5GHz-band ground fixed wireless access system using frequency bidding, the Ministry of Information Industry stipulates that in a city, a telecom operator can only apply for 10.5MHz of frequency resources (excluding Qingdao), and there is no protection belt between operators. 10.5MHz spectrum bandwidth, just reflects the R2000 airsun adjacent frequency point of the minimum channel interval of 1.75MHz advantage, we will 10.5MHz bandwidth divided into 6 1.75 MHz frequency points, respectively, in order for F1 ——— F6, will F1, F3, F5 These 3 frequencies are defined as a set, defined as F1, and the 3 frequencies of F2, F4, and F6 are defined as F2. In the seamless coverage, taking into account the interference of adjacent sectors, using the different frequency of adjacent sector configuration, each sector can be configured up to 3 basic units, occupy 3x1.75mhz frequency bandwidth, transmission 3x4mbps capacity. The typical 8-sector single base station has 96Mbps access capacity, and when one base station is covered by the largest 24 sectors, the total capacity of the system can reach 288Mbps. The above capacity is the net rate.

Capacity of the system to be expandable

Datang Telecom R2000 Airsun 3.5GHz adopts the module of sector access device, which supports uneven distribution of sector bandwidth and smooth expansion. Taking into account the frequency savings, initial investment and current customer distribution and demand, the operator of the first phase of the scheme we do not have the base station full configuration. First of all, for the more intensive areas of business focus, perfect coverage, the user density of small areas for partial coverage. The principle of Base station selection: Taking into account the distribution of existing access users and the types of requirements, but also taking into account the geographical environment of the city, combined with optical fiber transmission network, and strive to be in the urban area of a number of high points, but also the central station of the metropolitan Area Network, to achieve multiple base stations, multiple sectors, large According to the available bandwidth of 10.5MHz, divided into 6-channel carrier, frequency from F1 ——— f6, adjacent sectors using different frequencies for isolation, to ensure good transmission quality. According to the principle of demand-oriented and phased construction, the initial scheme can be covered and perfected under the condition of less investment and sufficient capacity.

In order to be able to use limited frequency resources for more users to provide quality telecommunications services, Datang Telecom fully considered the system expansion, the expansion of the program has the following:

Increase base station basic unit and remote station equipment in each existing sector. When the system is configured according to the frequency bandwidth of 3x3.5 MHz, if the adjacent sector has a isolation zone, the R2000 Airsun system can be configured with a maximum of 6 basic units per sector, providing 12E1 capacity and 10.5MHz frequency resources; If the adjacent sectors are covered seamlessly, R2000 Airsun system adjacent to two sectors to configure a different frequency, at this time each sector occupies 5.25MHz frequency resources, each sector can be configured with a maximum of 3 basic units, providing 6E1 capacity. According to the actual access user density per sector, the sector frequency resource can be distributed asymmetrically.

Increase the number of sectors. In a base station coverage area as the number of users increases and the user's demand for capacity increases, the capacity of each sector 6E1 can appear to be in a situation that is not satisfying. At this time, we can enlarge the sector by dividing the slice angle into small angle sector. Datang Telecom R2000 Airsun System The number of sectors in an access point can be configured 1x24 sectors according to user capacity and distribution.

Increase the number of base stations. According to market research and analysis, in order to provide more users with quality telecommunications services, can be built outside the existing base station to build more base stations to expand the system coverage area.

3.5GHz Frequency resource expansion. When the Ministry of Information Industry will expand the 3.5GHz frequency resources, Datang Telecom R2000 Airsun system has 2x100mhz frequency coverage ability, the system can be expanded smoothly after acquiring new frequency resources.

Adopt the way of multi band coverage to enlarge. Datang Telecom R2000 Airsun series products have 3.5ghz/10.5ghz/26ghz three frequency bands of equipment. Due to the limited frequency resources of 3.5GHz band, in the future, when we open 26GHz frequency resources in our country, we can build the 26GHz band R2000 Airsun system at the same site, and the R2000 Airsun system of these three kinds of frequency bands can be used in combination and managed by using the same set of network management software.

Reasonable cost-performance

A reasonable price-performance ratio is a key factor in the sustainable operation of the telecom operators who carry out the new business. Datang Telecom R2000 Airsun system provides a set of flexible, fast and low-cost application solutions for telecom operators. With a short construction cycle, flexible networking, later expansion of the convenience of the characteristics. Because the modular structure design makes the equipment easy to install and debug, it means that the cost and cost of the system are reduced, and it has the characteristics of flexible and easy to enlarge when the user increases the business demand later.

Users believe that Datang Telecom 3.5GHz system to comply with the principle of unified planning, phased construction, long-term development, not only protect the advanced nature and scalability of the network, and according to the current market demand, reasonable configuration of products and equipment, optimize the overall network, save project Investment, obtain the largest performance price ratio, Provides a comprehensive range of sustainable broadband wireless access network solutions.