tailieunhanh - Enhanced Radio Access Technologies for Next Generation Mobile Communication phần 7

Người nhận, mặt khác, nhiều tín hiệu nhận được trong mỗi kênh với một trọng lượng đầy đủ và cuối cùng kết hợp tất cả các kết quả đầu ra số nhân. Sản lượng bộ kết hợp được viết là | CDMA2000 1X 1X EV-DO 173 1xEV-DO Coverage LBA The coverage of the 1xEV-DO network refers to a zone where the service is provided at a certain throughput or higher throughput or a zone with a certain C I level or higher level. C I refers to the ratio between signal and interception. C indicates the transmission power from the base station and I indicates all interception signal power except carrier power C among the received power example of forward LBA could be found in Table 5. C _ PTX M gM 00 d IdO E Ề PTX M gMij d Ề PTX M gM 0j d N0 W i 1 j 0 j 1 Parameters Descriptions PTx M gN 0 d gM y d Now Transmission power of the cell Transmission loss between the AT and the AP Transmission loss between Ith AP and the AT in Jth sector Thermal noise Do System Capacity The forward link capacity of the 1xEV-DO network is determined by the MACIndex count that physically identifies the users. Table 6 shows the MAC Channel and preamble use versus MACIndex and total 59 MACIndex values can be used as traffic channels In the channel card of the 1xEV-DO there are 96 reverse channels. Therefore when there are three sectors each sector will have 32 channels. Unlike the CDMA 2000 1x network in the 1xEV-DO network it is the sector throughput not the number of subscribers which must be managed for the operation of the system. Depending on the location of the user and the number of users the actual sector throughput may drop below Mbps which is the maximum physical throughput. Major factors that affect the throughput include the early termination and multi-user diversity gain. Early termination occurs when the terminal requests a DRC that uses multi slots with repeated symbols see Table 7. The terminal responds by sending an ACK through the ACK channel when correct demodulation is made before receiving all slots that the base station sends. When the base station receives the ACK it will terminate the transmission without repetition. In short .