In this work, we exploit the radar clutter (i.e., the ensemble of echoes generated by the terrain and/or the surrounding objects in response to the signal emitted by a radar transmitter) as a carrier signal to enable an ambient backscatter communication from a source (tag) to a destination (reader). The proposed idea relies on the fact that, since the radar excitation is periodic, the radar clutter is itself periodic over time scales shorter than the coherence time of the environment. Upon deriving a convenient signal model, we propose two encoding/decoding schemes that do not require any coordination with the radar transmitter or knowledge of the radar waveform. Different tradeoffs in terms of transmission rate and error probability can be obtained upon changing the control signal driving the tag switch or the adopted encoding rule; also, multiple tags can be accommodated with either a sourced or an unsourced multiple access strategy. Some illustrative examples are provided.

翻译：在这项工作中，我们利用雷达杂波（即由地形和/或周围物体对雷达发射信号的响应产生的回波合集）作为载波信号，从源（标签）到目标（读取器）启用环境背散射通信。所提出的想法基于雷达激发周期性的事实，使得雷达杂波在比环境的相干时间更短的时间尺度上本身就是周期性的。在推导出方便的信号模型后，我们提出了两种编码/解码方案，不需要与雷达发射器协调或知道雷达波形。根据改变驱动标签开关的控制信号或采用的编码规则，可以获得不同的传输速率和误差概率的折衷；还可以使用已源泉或未源泉的多址访问策略容纳多个标签。提供一些说明性例子。