Example of the problem of TD wireless signal coverage (1)

Wireless signal coverage has always been a challenge for major operators. Especially in the dormitory area, system distribution in the building has been relatively difficult, so it is better to do wireless signal coverage outside. This article will give you a detailed example of Hebei mobile.

In the TD-SCDMA wireless network planning and construction, high campus deep wireless signal coverage has been a difficult point, especially in the dormitory area of colleges and universities, Macro Cell base station cannot effectively solve indoor wireless signal coverage, an indoor distribution system is required. However, it is difficult to build a distribution system in the dormitory because of the coordination of the owners, obstruction of students, and high investment, therefore, it is reasonable to use the outdoor distribution system for wireless signal coverage in the dormitory area of colleges and universities.

China Mobile Communication Group Design Institute Co., Ltd. Hebei branch analyzes the construction and testing of coverage projects in a dormitory area of a university, and puts forward reasonable suggestions for studying the deep coverage strategy of large school parks, we strive to solve the bottleneck of difficult campus coverage and meet campus network requirements based on reasonable planning to ensure network quality.

Analysis of wireless signal coverage strategies in dormitory areas of Colleges and Universities

The dormitory area of colleges and universities has the following features: users are intensive, communication time is relatively concentrated, and time is relatively long; indoor users have large demand for data services; buildings are intensive, and arrangements are relatively regular, wireless signals are easily blocked. wireless network coverage is difficult, and blind spots or blind spots are prone to wireless signal coverage. Property coordination and engineering implementation are difficult, affecting network coverage.

Based on experience and network planning and construction at home and abroad, campus coverage is mainly divided into the following solutions: Macro cellular coverage; micro cellular coverage for outdoor distribution systems; micro-cellular coverage in the indoor distribution system; macro-cellular + micro-cellular combined coverage.

At present, the school covers macro cells. This article mainly discusses the coverage of outdoor distribution systems.

Coverage Implementation Scheme

The study targets a university with three teaching labs, one integrated building, one office building, eight 6-story student dormitory buildings, and one 3-story canteen, 1 2-storey bath center. Requirements for eight of the students dormitory buildings, 1 canteen, 1 bath center TD-SCDMA wireless signal coverage, so that the dormitory mobile users can fully experience 3G services.

1. Requirement Analysis

◆ Pre-construction coverage analysis

The school dormitory area previously relied on macro cellular coverage. The indoor signals in the dormitory area were poor and could not meet the 3G business needs of users in the dormitory. In order to make the existing system meet the 3G requirement, 3G network wireless signal coverage needs to be carried out in the dormitory area of the school.

◆ User Estimation

Assume that the voice traffic of a single user is 0.02Erl in a dense area, the videophone traffic is 0.001Erl, and the average traffic of a single user in a data service is 1 kbps. If you use the KR algorithm to estimate the capacity according to the O3 configuration of a single residential area and consider the 75% load, the student capacity of each dormitory building in the campus is 716, which can meet the needs of users in a single dormitory building.

2. Distributed System Construction Plan

This project uses BBU + single channel RRU as the signal source. The main device consists of one BBU and six RRU. RF unit installation location:

This scheme adopts TDJ-182014A-45FT0 type oriented 60 cm board antenna, 1/2 feeder, 800 ~ 2500MHz splitter, coupler, etc.

3. Community Planning

Dormitory and living areas are divided as follows. dormitory and living areas are divided into 2 communities, and dormitory and bath center are divided into 1 community, 5 #, 6 #, 7 #, and 8 # dormitories and canteens are divided into one residential area.

4. frequency planning

This project uses the F1F2F3 network, where F3 is fixed to the HSDPA frequency point, and F1F2 is used as the frequency point for reuse. The planning results are as follows: