Age of information (AoI), defined as the time that elapsed since the last received update was generated, is a newly proposed metric to measure the timeliness of information updates in a network. We consider AoI minimization problem for a network with general interference constraints, and time varying channels. We propose two policies, namely, virtual-queue based policy and age-based policy when the channel state is available to the network scheduler at each time step. We prove that the virtual-queue based policy is nearly optimal, up to a constant additive factor, and the age-based policy is at-most a factor of 4 away from optimality. Comparison with previous work, which derived age optimal policies when channel state information is not available to the scheduler, demonstrates significant improvement in age due to the availability of channel state information. Our analysis relies on the age conservation law and age-square conservation law developed in this paper, which hold more generally and may be of independent interest.

中文翻译：

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通过完善的信道状态信息改善无线网络的信息时代


信息时效（AoI）定义为自上次接收更新生成以来经过的时间，是新提出的衡量网络中信息更新及时性的指标。我们考虑具有一般干扰约束和时变信道的网络的 AoI 最小化问题。当通道状态在每个时间步可供网络调度器使用时，我们提出了两种策略，即基于虚拟队列的策略和基于年龄的策略。我们证明，基于虚拟队列的策略接近最优，达到恒定的加性因子，而基于年龄的策略最多与最优相差 4 倍。与之前的工作相比，当调度程序无法获得信道状态信息时，得出了年龄最优策略，表明由于信道状态信息的可用性，年龄有了显着改善。我们的分析依赖于本文提出的年龄守恒定律和年龄平方守恒定律，它们具有更普遍的意义，并且可能具有独立的意义。