基于安全状态更新的信息年龄-能量权衡

Age of information-energy tradeoff based on security status update

考虑状态更新系统中传感器节点要尽可能及时地将随机生成的状态更新传送给基站,以信息年龄(AoI)作为时间新度量,同时引入平均保密年龄和保密年龄中断概率的性能指标,保证系统的通信安全性.采用实用的截断自动重复请求(TARQ)方案,传感器节点持续传输不断更新当前状态,直到达到允许的最大传输次数或生成新的状态更新.推导出平均AoI、平均峰值AoI的闭合形式表达式,以及平均能耗的表达式,通过优化物联网(IoT)设备的传输功率和平均传输功率约束下的最大允许传输次数来最小化平均AoI,实现系统的信息年龄-能量权衡.仿真结果表明,在相同的平均传输功率约束下,采用的TARQ方案比允许无限次重传的经典自动重复请求(ARQ)方案的平均AoI更低,性能更好.

Considering that the sensor node in the status update system should transmit the status update randomly to the base station as timely as possible, Age of information(AoI) was introduced as a new time measurement, and the performance indexes of average confidentiality age and secrecy age outage probability were introduced to ensure the communication security of the system. A practical truncation of automatic repeated requests(TARQ) scheme was adopted, in which the sensor node continuously transmitted and updated the current state until the maximum number of transfers allowed was reached or a new state update was generated. The average AoI, the closed form expression of the average peak AoI, and the expression of average energy consumption were derived, and then the average AoI was minimized by optimizing the transmission power of Internet of Things(IoT) devices and the maximum allowed transmission times under the constraint of the average transmission power, to realize the information age-energy tradeoff of the system. Simulation results show that the TARQ scheme has lower average AoI and better performance than the classical automatic repeat request(ARQ) scheme which allows infinite retransmission under the same average transmission power constraint.