Discussion on WCDMA wireless network planning and deployment principles

3G Early-stage network planning determines the network structure to a large extent, plays a decisive role in network investment and quality, and is the foundation of future network development. 3G Development, network quality is the most important, no good network quality to do support, no good business can not be achieved or better. The metrics for measuring network quality can be said to be numerous. For 3G, network planning, including wireless and core network planning, can be said to be an important means of achieving high quality networks. This paper focuses on the characteristics and advantages of Alcatel Shanghai Bell in helping operators to build high-quality 3G networks by analyzing the principles of WCDMA construction and wireless network planning.

1. WCDMA Networking principles-Three deployment phases

(a) Early stage of network construction

WCDMA technology itself determines that in the initial stage of network deployment should be a reasonable load to build a network, the network expansion of the use of increased carrier frequency, to increase the principle of the new station as a supplement. If the CDMA initially builds a thin network (low load) based on the overlay, the coverage gap between the base stations will be widespread as the capacity increases. Therefore, because of the capacity demand in CDMA networks to increase the new base station, and can not make the network capacity like the GSM network as linear growth, especially in urban dense areas, the base station spacing itself is very small, this phenomenon will be more serious. (Computer science)

In the initial network deployment, it is necessary to consider investment, use as little as possible base station, but also consider the long-term development of the largest possible network capacity potential. We propose to use ' tower to add dense urban load, the general urban area of a certain load ' program, so that the design of the network investment is relatively small, expansion potential. In the selection of equipment should be based on indoor macro-cellular base station, not only can ensure a very high network performance, and network planning flexible expansion potential. At the same time, in order to low-cost, rapid solution of highways and basements, such as low coverage demand area, the use of a small number of micro-cellular base station combined network.

With the growth of users ' business, especially the increase of asymmetric business, downlink capacity will become a bottleneck. At this point, you can increase the downlink capacity by using high power amplifiers, transmitter diversity, and HSDPA.

(b) Network development period

To the network development period, the user demand presents the diversification trend, the network appears the traffic hot spot area and the coverage blind zone. In order to attract more new users to join, expand the network coverage scale, provide a variety of business services, reduce the price of services has become the focus of the operation of the operator this stage. In addition to considering urban outdoor coverage, it is important to consider indoor coverage in densely populated areas. In the network construction, in addition to the standard indoor-type Acer cellular base station, the introduced equipment type there are also the following: Super large capacity indoor base station, compact outdoor macro-cellular base station, micro-cellular base station, high-power micro-cell base station, RF remote Unit; In order to solve the hot spots, subways, tunnels and other special terrain coverage, Distributed Antenna systems or RF leakage cables are usually used.

(c) Network maturity

In the period of network maturity, WCDMA network frame structure has been formed, covering demand has been realized, large-scale network construction has been completed; In order to further improve the quality of service, network planning and construction of the focus from the overall network construction into local network region optimization adjustment work. According to the network performance statistics and user complaints reflect, the network unit layout, parameters, such as the optimization of the implementation, including the relocation of the base station and add new sites.

2. Wireless network planning-building a profitable network

A) The difficulties and challenges of WCDMA wireless network planning

In WCDMA Wireless network planning, it is necessary to take into account the system of CDMA key technologies such as: power control, soft switching and more soft switching factors such as the impact on wireless planning. Because WCDMA system introduces a variety of data services and multiple business environments, it makes system planning more difficult. The wireless network planning of WCDMA system is to seek the balance between capacity, coverage and service quality, and the three are dynamic change, so it is more challenging.

The ultimate goal of network planning is to provide operators with a set of profitable network, requiring the lowest comprehensive cost, that is, to ensure that the above excellent network coverage, gold service varieties on the basis of comprehensive planning costs, construction costs, the lowest cost of operation and maintenance.

b The characteristics and advantages of Alcatel Shanghai Bell Network Design

Alcatel Shanghai Bell has extensive experience and advanced technical strength in 3G wireless network design and planning. Excellent wireless network design ideas, rich network planning experience and excellent network planning tools, including the use of emerging building databases, can be more accurate for customers to plan the results, save the network investment while , but also to customers to share valuable domestic and foreign wireless network planning experience.

Alcatel Shanghai Bell has unique tools and algorithms:

Have their own set of design tools, network design tools are airmust, planning tool is 9155;

Overlay and capacity are balanced by iterative methods.

Because of the limited mechanism of uplink and downlink, in the iterative process, the upper and lower links are separated, after in-depth study and analysis of the characteristics of WCDMA technology, in the uplink and downlink load and interference calculation process to introduce a series of new parameters and methods to make the design results more accurate. Alcatel Shanghai Bell in the process of the link budget, considering all the users in the community (including the neighborhood) of the total interference, the entire business is linked to the budget, so as to obtain the different coverage of each business. The use of advanced up and down line link Iteration budget concept, the determination of the radius of the community more scientific and reasonable, to avoid the common network design algorithm is very easy to bring cover empty or base station surplus phenomenon, for operators to save the investment of the distribution station.

In the process of network design, fully consider the development of various business, calculate the various stages of business coverage. So that the design scheme can meet the coverage and capacity requirements of the whole stage. Avoid coverage and capacity issues arising from business development and respiratory effects

In the process of network design, in order to overcome the phenomenon of cell respiration with the increase of traffic, and the different requirements of capacity and coverage in different environmental communities, the following measures can be taken: multicarrier, sector splitting, top amplifier TMA, high power amplifier, transmitter or receiver diversity, micro-honeycomb, indoor station, etc. Because of different solutions and special functional working principles, the impact on the downlink capacity and coverage of the network is also different, Alcatel Shanghai Bell is a deep analysis of the features of each feature and the network's current problems, and ultimately determine a reasonable and efficient solution.