Research On Optimization Method Of CDMA Network Indoor Coverage Solution

Acoording to survey, most of mobile communication traffic has actually occurred indoor, especially for data services. With the rapid development of 3G networks, the indoor coverage of mobile networks has become increasingly important in terms of QoS. How to improve capacity, performance and utilization of indoor coverage system are important issue that mobile network operators have to face.Currently China Telecom CDMA indoor wireless overlay network has applied a large number of repeater source and trunk amplifier signal distribution systems, owing to historical reasons. This indoor overlay construction mode can’t provide enough system capacity, meanwhile problems including reverse interference noise and noise floor uplift caused by the repeater stations and trunk amplifier will reduce the quality of indoor coverage systems and business experience. Moreover, traffic absorption and utilization of indoor network resources are low as the network works on the same frequency indoor and outdoor.In order to improve the performance and quality of CDMA indoor coverage systems for higher resource efficiency higher business experience, this thesis address an optimized solution for wireless indoor overlay to solve typical problems that puzzle current CDMA indoor system in three aspects. Firstly, flexible networking and capacity needs can be fulfilled by deployment of distributed base station plus passive indoor distributed system; Secondly, characteristics different-frequency can be applied to deal with interference on indoor network from outdoor network and eliminat common high-pollution to improve indoor network traffic capacity and reduce pressure of outdoor macrocell network load and expansion; finally, PN indoor source requirements in dense-business urban area can be decreased by PN solutions,which can also help on neighborhood planning, network switch and network planning.The present network test of China Telecom actual indoor overlay deployment projects fully prove feasibility of above solutions improving netwok resource utilization and simplifying network planning, including Beijing Telecom office building indoor coverage project and Nanjing Hotel and new centrury plaza indoor coverage project. This solution will provide effective guidance for future indoor network deployment and optimization program by China Telecom and is under large-scale promotion.