论文标题
通过无限抽样编码的时间:理论,算法和硬件验证
Time Encoding via Unlimited Sampling: Theory, Algorithms and Hardware Validation
论文作者
论文摘要
传统均匀采样的一种替代方法是时间编码,该采样将连续时信号转换为触发时间流。这引起了事件驱动的采样(EDS)模型。在功耗和时间分辨率方面,EDS获取的数据驱动性质是有利的,并且受到生物神经系统中信息表示的启发。如果模拟信号在预定义的动态范围之外,则EDS会产生低密度的触发时间,从而导致由于混叠而导致恢复失真。在本文中,受到无限传感框架(USF)的启发,我们提出了一种新的EDS体系结构,该体系结构在获取之前纳入了Modulo非线性,我们将其称为Modulo EDS或Meds。在Meds中,模量非线性将高动态范围输入折叠到低动态范围幅度,从而避免恢复失真。特别是,我们考虑异步Sigma-Delta调制器(ASDM),以前用于低功率类似物到数字转换。这种基于新型药物的采集是通过对Modulo非线性的最新概括称为Modulo-迟发性的。我们根据采样率标准设计了一种数学上保证的恢复算法,并提供了重建误差范围。我们超越了数值实验,还为我们的方法提供了第一个硬件验证,从而弥合了理论和实践之间的差距,同时证实了我们作品的概念基础。
An alternative to conventional uniform sampling is that of time encoding, which converts continuous-time signals into streams of trigger times. This gives rise to Event-Driven Sampling (EDS) models. The data-driven nature of EDS acquisition is advantageous in terms of power consumption and time resolution and is inspired by the information representation in biological nervous systems. If an analog signal is outside a predefined dynamic range, then EDS generates a low density of trigger times, which in turn leads to recovery distortion due to aliasing. In this paper, inspired by the Unlimited Sensing Framework (USF), we propose a new EDS architecture that incorporates a modulo nonlinearity prior to acquisition that we refer to as the modulo EDS or MEDS. In MEDS, the modulo nonlinearity folds high dynamic range inputs into low dynamic range amplitudes, thus avoiding recovery distortion. In particular, we consider the asynchronous sigma-delta modulator (ASDM), previously used for low power analog-to-digital conversion. This novel MEDS based acquisition is enabled by a recent generalization of the modulo nonlinearity called modulo-hysteresis. We design a mathematically guaranteed recovery algorithm for bandlimited inputs based on a sampling rate criterion and provide reconstruction error bounds. We go beyond numerical experiments and also provide a first hardware validation of our approach, thus bridging the gap between theory and practice, while corroborating the conceptual underpinnings of our work.