The period after the COVID-19 wave is called the Echo-period. Estimation of crowd size in an outdoor environment is essential in the Echo-period. Making a simple and flexible working system for the same is the need of the hour. This article proposes and evaluates a nonintrusive, passive, and cost-effective solution for crowd size estimation in an outdoor environment. We call the proposed system as LTE communication infrastructure based environment sensing or LTE-CommSense. This system does not need any active signal transmission as it uses LTE transmitted signal. So, this is a power-efficient, simple, low-footprint device. Importantly, the personal identity of the people in the crowd cannot be obtained using this method. First, the system uses practical data to determine whether the outdoor environment is empty or not. If not, it tries to estimate the number of people occupying the near range locality. Performance evaluation with practical data confirms the feasibility of this proposed approach.

中文翻译：

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使用CommSense仪器估算COVID-19回声周期的人群大小

COVID-19波之后的时间段称为回声周期。在回声期间，估计室外环境中的人群规模至关重要。为此，需要一个简单而灵活的工作系统。本文提出并评估了一种非侵入性，被动且经济高效的解决方案，用于在室外环境中估算人群规模。我们将提议的系统称为基于LTE通信基础设施的环境感知或LTE-CommSense。由于该系统使用LTE传输信号，因此不需要任何活动信号传输。因此，这是一款省电，简单，占地面积小的设备。重要的是，使用这种方法无法获得人群中人们的个人身份。首先，系统使用实际数据来确定室外环境是否空旷。如果不，它试图估计占领近距离地点的人数。用实际数据进行性能评估证实了该方法的可行性。