Hierarchical Token Rings for Address-Event Encoding

Address-event representation (AER) is an event-driven, neuromorphic inter-chip encoding and communication protocol originally proposed to communicate location and timing information of sparse neural events between neuromorphic chips. The protocol is widely used in bio-inspired, event-based vision sensors to communicate visual events. The same approach has been explored for scientific imaging applications, but the performance of existing encoding schemes degrades in the presence of large sensor arrays and a wide range of event rates. In this paper, we introduce a new AER encoding scheme based on hierarchical token-rings (HTR), which blends event-based and scanning approaches. We show that HTR offers significant improvement in latency, throughput, and power compared to existing tree-based approaches in the context of scientific imaging applications.