Distributed UWB Radio Sensing With Clock-Free CIR Synchronization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional monostatic UWB systems rely on a centralized clock/timing source, limiting their spatial distribution and making it difficult to synchronize and align channel impulse responses (CIRs) in distributed UWB architectures, which hinders fine-grain sensing and radar-like functionality.
Innovation Solution
A method for synchronizing and aligning CIRs in distributed UWB systems by upsampling, aligning CIRs based on a leading edge, estimating phase noise using a line-of-sight path, and eliminating phase noise through subtraction, enabling phase error correction across separate and independent UWB nodes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a centralized clock/timing source is used in UWB systems, then timing synchronization is achieved, but spatial distribution and system scalability are limited
Solution Approach 1:
The system divides the centralized timing function into distributed autonomous timing operations at each node. Each UWB node independently generates and processes timing signals without relying on a central clock, enabling spatial distribution while maintaining synchronization through peer-to-peer coordination of channel impulse responses.
2Adaptability or versatility
If distributed UWB architecture is implemented without centralized timing, then spatial distribution and scalability improve, but synchronization and alignment of channel impulse responses become difficult
Solution Approach 1:
The system employs feedback mechanisms where each node transmits and receives UWB signals, extracts channel impulse responses, and uses the received CIRs to adjust and synchronize its own timing. The phase noise estimation and elimination processes use feedback from the received line-of-sight signals to correct timing alignment, enabling precise CIR synchronization in distributed architecture.
Solution Approach 2:
The patent introduces phase noise estimation and elimination as intermediary processes that mediate between distributed timing sources. By estimating phase noise from received CIRs and eliminating it through subtraction, the system creates a common reference frame that enables precise CIR alignment without requiring direct access to a centralized clock.
3Adaptability or versatility
If phase noise is present in distributed UWB nodes, then independent operation is maintained, but sensing precision and radar-like functionality are degraded
Solution Approach 1:
The system converts the harmful effect of phase noise into a useful measurement tool. By estimating phase noise from the received line-of-sight signals and using it to correct the CIRs, the system transforms what was previously a source of error into a reference for synchronization. The phase noise estimation process itself provides information about the channel conditions that can be used to improve sensing precision.
Data Source
AI summary
A distributed ultra-wide band (UWB) radar system and methods for operating the same are disclosed. The distribute radar system uses a plurality of separate UWB radios or nodes that do not use a centralized clock or source of time. However, the distributed UWB system operates to provide radar-like functionality and fine-grain sensing capabilities through synchronization based on line-of-sight (LOS) signal processing and noise estimations. Synchronized channel impulse responses (CIRs) can be processed for general object detection and tracking, gesture recognition, or even micro-motions such as monitoring vitals