Study On Sino-DPRK Border Transboundary Problems Of CDMA Signals

Jilin province Baishan City and North Korea across the Yalu River. While white mayor white county and North Huishan the third largest city of the horizontal distance of less than 50 meters, North Korea without a mobile communication network, and asked our country CDMA signals cannot be in the territory of use. To ensure China signal satisfies the users normally use to ensure that the 50 meters North Korea signal cannot be used, according to the wireless signal propagation characteristics, can minimize the area covered by the signal at the same time, the crossing signal control can be achieved the requirements. Because of China's border with North Korea between the lack of shelter, so the difficulty of the problem is how to airborne signal control.In the signal control, traditional optimization methods, including adjusting the transmitted carrier power, adjust the overhead channel transmitting power, adjust the antenna angle and tilt angle, reduce the height of aerial, replacing a smaller gain antenna manner, by increasing the base station to adjust the network structure, the above shortcomings in traditional optimization methods, relatively simple, the cost is relatively high, and the the lack of precise control. This article mainly aims at the North Korea proposed in its border territory cannot call demand. First, in a simulated environment by trying to traditional optimization means and after the actual test proved unable to solve the problem; then according to the characteristic of CDMA system, the principle of CDMA, CDMA interference of in-depth study, by adjusting the field to control the signal coverage area antenna angle for the purpose of, and open community access distance control function; finally the wireless environment to meet access distance control area, the increase in forward interference device by means of strengthening the more precise control. Through field test and North Korea feedback results, the solution to our signal more area to North korea.Using access distance control and forward interference device combining, deal with the border covering problem, realized in the North Korean border cannot be dialed telephone request, has been North Korea's affirmation. Effectively save the new base station investment, reduce the construction costs, improve the quality of network service, reduce customer complaints, become the first domestic uses the solution to border area signal more effectively solve the problem, has opened up a new network optimization means, with great economic significance and popularized significance.