Wi-Wi：纳秒级无线时间同步技术
在NAB展会上，作者发现了来自日本NICT的Wi-Wi STAMP无线时间同步协议演示。Wi-Wi代表"无线双向干涉测量法"，利用900MHz频段实现皮秒级时间同步和毫米级距离精度，设备目前仅有智能手机大小。现有原型具备20ps相位同步抖动和30ns时间同步精度，下一代产品在实际使用中将达到5ns以内的时间同步。该技术仍在开发中。
相关报道
Jeff Geerling tests a prototype wireless time synchronization system called Wi-Wi, which can achieve sub-5 nanosecond accuracy using off-the-shelf components. The system works by measuring round-trip signal delays over WiFi-like radio links to precisely synchronize clocks.
The ertm15-llrf-wr project on GitLab provides a high-performance White Rabbit timing receiver designed for achieving femtosecond-level jitter accuracy. It is part of the Open Hardware Repository (OHWR) and focuses on precise time synchronization for applications requiring extremely low timing errors.
White Rabbit is an open-source project providing sub-nanosecond synchronization for large distributed systems, developed at CERN. It extends Ethernet with precise time transfer for deterministic data delivery across thousands of nodes.