IMS的全称是（）。A、Integrated Mobile SolutionB、IP Multimedia SybsystemC、Intelligent Mobile SystemD、Interesting Multiple Service

Recently,telecommunication carriers has been building ( ) core networks in order to effectively support various kinds of fixed and mobile broadband services.

A. NGN B.social network C. mobile network D. AII -IP

A.Moving WiFi

B.Mobile WiFi

C.Micro WiFi

D.Minor WiFi

With the explosive popularity of mobile devices, we have witnessed a steady increase in demand for mobile date service. In addition mobile users also expect to connect to the Internet for communicate and access to services through the best suitable connection, anywhere and at anytime. Although the seamless roaming capability is well supported in conventional. Cellular communication networks, roaming and interworking technologies are still immature in heterogenous wireless networks. Seamless roaming over heterogenous wireless networks will be an ongoing and improved process, due to the requirements from both end users and network administrators. From the wireless access networks belonging to different administrative domains, mobile users cannot always identify at every instance which network is the best one to access for their service. It is highly demanded to establish a network architecture which can facilitate mobile terminals to access the appropriate network in a cost-effective way. If a mobile user wants to move from one network to another with continuous service, the terminals have to cope with network change to maintain service seamlessly. Quality of service is a major issue that the end users should be provided with the satisfying service, while the network workload and cost should not too much increased. In addition, since end users are provided with numerous service ranging from Voice-over-IP to Video-on-Demand services, it is expected that users can experience the same quality for all the different service. Therefore, the network architecture need to be designed in such a way that the quality mechanism is incorporated so that users are served according to their individual QoS requirements. Based on the paragraph above, at present, seamless roaming over heterogenous wireless network is () in conventional cellular communication networks, Because of (), mobile users cannot always identify at every instance which network is the best one to access for their services. To satisfy the users QoS requirements, the network architecture design should include () A.better than

B.maturer than

C.as good as

D.not as good as

49.A.the different network administrative domains

B.the same network administrative domains and mobile users

C.mobile users

D.the same network administrative domains

50.A.Voice -over -IP

B.the quality mechanism

C.workload

D.Video-on-Demand

请帮忙给出每个问题的正确答案和分析，谢谢！

【Recently， telecommunication carriers has been building All-IP core networks in order to effectively support various kinds of fixed and mobile broadband services，such as up-and down-loading You tube and SNS（Social Networking Services）with rich video file，as well as broadband mobile Internet services. Such All-IP network is called NGN（Next Generation Network），which guarantees secure authentication and QoS such as the bandwidth and the delay. From the service point of view，convergence of fixed and mobile communications，known as FMC（Fixed Mobile Convergence）is becoming a key increasing new services and expanding the market.】 Form the paragraph above，we can see that（）can be defined as a network that can effectively support various kinds of fixed and mobile broadband services，with guaranteed QoS in terms of（）and etc. And the key to develop new services and gain larger market share should be（）

A．All-IP access network B．broad band network C．NGN D．social network A．data rate B．error rate C．availability D．band width， delay A．mobile communications B．Internet C．All-IP core network D．Fixed Mobile Convergence

A.Mobile Number Group

B.Triplet

C.Triplet Group

D.AUC

CDMA for cellular system can be described as follows. As with FDMA, each cell is allocated a frequency （71） , when is split into two parts, half for reverse (mobile unit to base station) and half for （72） (base station to mobile unit). For full-duplex （73） , a mobile unit both reverse and forward channels. Transmission is in the form. of direct-sequence spread （74） , which used a chipping code to increase the data rate of the transmission, resulting is an increased signal bandwidth. Multiple access is provided by assigning （75） chipping codes to multiple users, so that the receiver can recover the transmission of an individual unit from multiple transmissions.

A.ware

B.signal

C.bandwidth

D.domain