The Study Of The Performance Of LTE System Covers

LTE (Long Term Evolution) is the Long Term Evolution of3GPP, which is a transition between the3G and4G technology, and is the global standard of3.9G. Using OFDM and MIMO as the sole criterion for the evolution of its wireless network and providing downstream100Mbit/s and uplink50Mbit/s peak rate under the20MHz spectrum bandwidth, LTE has been improving and enhancing the3G air access technology, improving the user’s performance of cell edge, and increasing the cell capacity and reducing system latency.From the experience of3G network construction and operation and maintenance, good wireless coverage is the fundamental survival of all mobile networks, which affect the end-user experience directly. With the same frequency interference characteristics, TD-LTE technology’s early stages of network planning and coverage performance analysis have profound effect on its latter part of the network. Typically, good coverage planning can save a lot of late optimize workload, and good wireless coverage is a powerful means of shaping the operator brand, enhancing the competitiveness at the same time, the importance of which is self-evident.In order to study the performance of3GPP LTE coverage, firstly, this paper has studied the frame structure, the pilot structure, the physical layer structure of the existing LTE, and then examined the key technologies of the LTE physical layer OFDM and MIMO and gave MIMO and OFDM system model, which the paper has researched and analyzed, and discussed SFR technology. This article commenced as the basis for the derivation of the formula below.The study showed that the TD-LTE air interface signal transmitting power directly affects their coverage performance, so the calculation of the transmission power is particularly important. For common reference signal CRS as an example, this paper has considered the factors of the MIMO technology, OFDM technology, soft frequency reuse, and so on. Firstly, the paper has analyzed the downlink of a single RE, receiving the UE received power, and then analyzed the noise and interference of the LTE system, than finally concluded the formula of single port downstream signal C/(N+I), which has some reference value for study of transmit power of the LTE system and covering the performance.Finally, the paper has verified the theoretical findings. Combining characteristics of LTE FDD systems, the paper has analyzed the link budget parameters, and focused on LTE FDD system link budget method, then studied to determine the cell radius and single-station coverage area, according to the link budget. For mobile communications network operators, the accuracy of the link budget relates to the LTE network coverage quality and construction costs, so that network link budget and coverage estimates of LTE FDD are both complex and critical issues of LTE FDD network deployment process. The method in this paper can be used for LTE FDD network planning and design.