针对无线传感器网络中拒绝睡眠攻击严重降低网络寿命的问题,提出了一种参考接收信号 强度指示的虚假调度切换方法.该方法采用接收信号强度指示协助检测拒绝睡眠攻击节点的存在 性,当检测结果为真时,启动虚假调度切换,即在受攻击者一跳范围内广播调度切换信息, 并在定时 器超时后回到初始调度状态,从而使攻击者耗费大量能量测量和跟踪调度周期, 以至于过早死亡, 保护了正常节点的工作, 使其能够摆脱或躲避恶意节点的攻击. 在 NS2
29平台上,采用标准 S- MAC模块进行了仿真.结果表明,该策略能够有效地减少恶意节点碰撞、 广播和能量衰竭攻击的影 响,在牺牲了一定的能量和时延的情况下,保证了网络的健康程度并减少了丢包率.

为解决移动无线传感器网络中节点连通性较弱的问题，提出一种包含不同移动性节点的无线传感器网络 提升移动节点连通性的保障时隙(GTS, guaranteed time slot)分配策略。首先，采用Kalman滤波预测模型得到用户 下一阶段位置；接下来，引入一种考虑速度、方向和相对移动性的节点移动程度界定方法，并在此基础上进行 GTS预约优先级的初步确定；随后，根据移动节点对所预约时隙的使用反馈情况自适应调整预约优先级；最后， 根据节点的优先级决定 GTS 时隙的使用顺序及额外预留时隙的使用权。仿真结果显示，提出的分配策略在具有 不同移动性节点的网络中， 能够提高移动节点接入的成功率， 保证较低的分组平均传输时延及较高的分组投递率。 此外，采用基于反馈机制的自适应预约优先级调整策略能够显著增加整个网络中已分配时隙的正确使用率。

首先利用仿真工具产生了无线自组织网络中多种场景下的业务量，随后对业务量进行定性分析并验证了 其内在的自相似性。接着根据自相似 Hurst 参数与投递率、分组传输平均时延之间的关系建立了模糊控制模型， 并给出了基于反馈的自适应模糊规则调整方法。仿真数据显示，AMMWHA（adaptive MANET mobile model with Hurst adjustment)模型与其他几种典型移动模型相比，由于采用了业务量自适应的移动控制机制，在投递率、分组 传输平均时延和丢包率上都有较大改进。

With an ever-increasing interests and demands in Near-Space , more and more researchers have put their attentions on this field, leading to an emerging needs for modeling the 20~100km altitude space especially for broadband communications. Among the lots of works, Media Access Control (MAC) undoubtedly has chief importance and urgency with which communicating objects or nodes can effectively access to Near-Space. However, previous MAC designs mainly focus their attentions on service differentiation by application purposes without considering nodal mobility. In fact, access control for nodes with different mobility levels has significantly influences to MAC performance and is complex and difficult to be implemented together with present MAC protocols. In this paper, we first presented a location method for Near-Space vehicles such as airships and unmanned planes and then modeled the mobile networks infrastructure with mobility considered. For determining the vehicles joining/leaving events locally, we quantify the communication range with Received Signal Strength Indicator (RSSI) aid. Then, for better managing the nodes access to the Near-Space with aforementioned works, we designed a TDMA based reservation MAC protocol to guarantee the service delay and networks coverage with best efforts. Simulation results showed that our proposed model better fit for Near-Space mobile communication environments and presented a lower delay and higher coverage regarding to different mobility levels.

该文针对 Ad hoc 网络中同时存在的快、慢衰落情况，提出一种依据节点信号干扰噪声比(Signal to Interference plus Noise Ratio，SINR)计算并行传输门限的方法。该方法在获知节点信道质量的分布情况后，采用 贝叶斯非合作博弈理论对不同源目的节点对之间的并行传输进行建模。 考虑到该模型会使信道质量长时间低于并行 传输门限的节点处于发送“饥饿”状态，该文引入协作通信机制来解决“饥饿”节点的并行传输问题，且与已存在 的源目的节点通信对并存。仿真结果显示，该文提出的CTCG (Concurrent Transmission based on Channel quality with Game theory aid)模型能较大程度增加Ad hoc网络的并行传输机会， 提高系统吞吐量， 且能够较好的解决 “饥 饿”节点的发送抑制问题。