In this paper, we analyze the impact of different encoding schemes on the age of information (AoI) performance in a point-to-point system, where a source generates packets based on the status updates collected from multiple sensors and transmits the packets to a destination. In this system, we consider two encoding schemes, namely, the joint encoding scheme and the distributed encoding scheme. In the joint encoding scheme, the status updates from all the sensors are jointly encoded into a packet for transmission. In the distributed encoding scheme, the status update from each sensor is encoded individually and the sensors' packets are transmitted following the round robin policy. To ensure the freshness of packets, the zero-wait policy is adopted in both schemes, where a new packet is immediately generated once the source finishes the transmission of the current packet. We derive closed-form expressions for the average AoI achieved by these two encoding schemes and compare their performances. Simulation results show that the distributed encoding scheme is more appropriate for systems with a relatively large number of sensors, compared with the joint encoding scheme.
翻译:在本文中,我们分析了在点对点系统中不同编码办法对信息年龄(AoI)性能的影响,在这个系统中,一个源根据从多个传感器收集的状态更新生成包件,并将包件传送到目的地。在这个系统中,我们考虑两个编码办法,即联合编码办法和分布式编码办法。在联合编码办法中,所有传感器的状态更新都被联合编码成一个传输包。在分布式编码办法中,每个传感器的状态更新被单独编码,传感器包件按照圆盘刺政策传输。为了确保包件的新鲜性,两种办法都采用零等待政策,一旦源件完成当前包件的传输,立即生成新的包件。我们从这两个编码办法中获得的平均AoI的闭式表达方式,并比较其性能。模拟结果显示,分布式编码办法对于传感器较多的系统更为合适,而联合编码办法则比较联合编码办法。