Mobility Management in Next Generation Wireless Systems

未来的无线移动系统承诺普遍覆盖，并要求终端能够在网络之间无缝漫游，这可能是不同类型的。下一代移动终端将必须存在于多种标准的世界中，移动性管理程序(即位置注册、寻呼和切换)将必须跨网络提供商和网络主干以及地理区域进行互操作。将研究位置注册、寻呼和切换，并将引入新的协议来解决这些问题。从位置管理的角度来看，为了预留无线资源，移动终端必须在进入新系统之前进行注册。此外，必须转换信令格式，并且必须对移动终端进行认证。提出了一种新的方案，该方案估计用户的移动性模式，以便为新的协议提供帮助，并估计新的移动性管理过程的信令开销。此外，还引入了一种新的系统间位置更新方案，该方案通过基于每个用户的配置文件分配更新距离阈值来减少信令通信量。此外，还引入了边界位置区，使MTS能够请求两个不同系统之间的位置更新。未来无线系统的另一个问题是系统间寻呼问题。搜索操作不仅可以在移动终端最后注册的系统中执行，而且可以在移动终端自上次呼叫以来经过的系统中执行。提出了一种新的方案，该方案将寻呼区域按照位置概率的降序进行合并和重新排序，直到延迟界达到一定的阈值作为服务质量参数。对于切换管理，无线接入系统必须支持具有多个连接的移动终端的系统间切换，这些移动终端正在发送和接收具有不同服务质量(Qos)期望的多媒体业务。无线电信号强度必须在不同的空中接口和功率级别上进行测量和比较，并且信令程序必须在每个系统的交换机之间进行协作。提出了一种新的系统间切换方案，当移动终端开始切换到新系统时，使用边界小区来执行系统转换。最后，将开发一种新的信令协议，将移动终端切换到边界小区，执行格式转换，然后将移动终端切换到新系统。

Future wireless mobile systems promise universal coverage and require terminals to be capable of seamless roaming between networks, which may be of different types. Next generation mobile terminals will haveto exist in a world of multiple standards, and mobility management procedures (i.e., location registration, paging and handoff) will have to be interoperable across network providers and network backbones as well as geographical regions. Location registration, paging and handoff will be investigated, and new protocols will be introduced to solve these problems. From the standpoint of location management, the mobile terminals must register before they enter new systems in order to reserve radio resources. In addition, the signaling formats must be converted and the mobile terminals must be authenticated. A new scheme is proposed, which estimates the user mobility pattern in order to help new protocols and to estimate the signaling costs of the new mobility management procedures. Also, a new intersystem location update scheme is introduced, which reduces the signaling traffic by assigning update distance thresholds based on a per-user profile. Furthermore, the boundary location area is introduced, which enables the MTs to request location update between two different systems. Another problem for future wireless systems is the intersystem paging problem. The search operation may be carried out not only in the system where the mobile terminal last registered, but also in the system the mobile terminal has passed since the last call. A new scheme is proposed that combines and reorders the paging areas in decreasing order of location probabilities, until the delay bound has reached a certain threshold value as a QoS parameter. For handoff management, the radio access system must support intersystem handoffs for mobile terminals with multiple connections that are sending and receiving multimedia traffic with different Quality of Service (QoS) expectations. Radio signal strengths must be measured and compared across different air interfaces and power levels, and signaling procedures must cooperate between the switches of each system. A new intersystem handoff scheme is proposed that uses boundary cells to perform system transformations when mobile terminals begin to handoff into new systems. Finally, a new signaling protocol will be developed to handoff the mobile terminal into the boundary cell, perform the format transformation, and then handoff the mobile terminal into the new system.