In this year

a large scale of network construction

including infrastructure of BS

iron towers and transmission network

are co-headed by the three local telecom operators

namely China Mobile

China Telecom and China Unicom. One of the most important characteristics of this collaboration is that the infrastructure will be shared by several wireless systems with different standards. Thus

the consideration of both the distances of antennas and the coordination of interferences between different wireless systems has become extremely important among the solutions for infrastructure sharing designing and executing. To encounter the interference between different systems

the general way is to upgrade the iron towers in antenna systems

to guarantee the interval between antennas

to avoid the interference between the signals of different frequencies.