tailieunhanh - TEAM FLY WIRELESS NETWORK DEPLOYMENTS phần 3

Như vậy, chúng tôi kết thúc kiểm tra lái xe, thu thập dữ liệu và điều chỉnh mô hình. Thậm chí sau đó, một lợi nhuận từ 8 đến 10 dB nhận được mức tín hiệu được cho phép trong thiết kế cuối cùng. Đây là những thực tế của thiết kế RF với sự tôn trọng để triển khai di động. | 42 Chapter 5 interference creating dominant servers managing handoff activity and handling non-uniform and time-varying traffic distributions. It also provides the ability to decouple the analog and digital sector configurations. With smart antennas a single physical array antenna can be used to synthesi e completely different sector nonfigurations for the digital and analog services. As the following sections will illustrate there are strong theoretical and practical reasons that optimum CDMA sector settings are much different from optimum analog nonfigurations for example it may be desirable to implement DMA as a 6-sector configuration while maintaining an underlying analog S-seetor network. Smart nntennas enable such fleXibi 1 ity in deployment snd optimization whi 1 e sharing a common antenna arny for both analog and digital services or among mu111p 1 e digital services . vehicular voice high rate data service w ireless local ioop and private networks . In cellular systems where antennas are shared between analog and CDMA service providers are forced into fixed grid patterns due to the underlying Uequency reuse assignments of the analog network. Without a smart antenna system azimuth pointing angles of the oectors are Socked into a rigid hexagonal grid pattern which forces all alpha tea and gamma sectors both analog and CDMA to be aligned across the network. However since CDMA is based on unity frequency reuse shere is no need to maintain a rigid grid pointing pattern fcross the s telDMA network. Traffic Load Balancing Statistics derived from commercial cellular and PCS networks consistently indicate that taffic loads are unevenly distributed across cells and sectors. In other wo rds It s quite common for a cell to have a single sector near foe blocking point w hile the tel s other two sectors are lightly loaded. Traffic data from a number of cellular and PCS markets show that on sv e the highest loaded sector has roughly 1 of the traffic it would .