비동기 UWB 앵커 노드를 이용한 단방향 거리 측정 기반 위치 추정 기법 = One-Way Ranging (OWR)-Based Positioning Technique with Time-Asynchronized UWB Anchor Nodes

국문 초록 (Abstract)

최근 위치 기반 서비스에 대한 수요가 증가하면서 정밀한 위치 추정 기술의 중요성이 커지고 있다. 특히 UWB 기술은 500MHz 이상의 넓은 대역폭을 활용하여 cm 수준의 정밀한 거리 및 위치 추정이 가능하여 주요 스마트폰제조사들이 UWB 기술을 적극적으로 도입하고 있다. UWB 거리 추정 방식은 양방향과 단방향 방식으로 구분되는데, 그중 단방향 방식은 비교적 간단하게 동작한다는 장점이 있지만 UWB 기기 간의 시간 동기가 정밀하게 유지되어야 한다는 제약 조건이 있다. 본 논문에서는 이러한 한계를 극복하기 위해 모바일 기기와 앵커 노드가 시간동기화가 이루어지지 않은 조건에서 칼만 필터를 이용하여 비동기를 추정하고 따라서 정밀한 위치 추정을 가능하게 하는 새로운 단방향 거리 측정 기반 위치 추정 기법을 제안한다. 모의실험을 통해 제안한 기법의 위치 추정성능을 검증하였으며 오차 범위 이내에서 모든 기기가 동기화된 이상적인 상황과 유사한 성능 달성이 가능함을확인하였다.

다국어 초록 (Multilingual Abstract)

With the increasing demand for location-based services, precise location estimation technology is becoming increasingly important. In particular, UWB technology enables precise location estimation at the centimeter level by utilizing a wide bandwidth of more than 500 MHz, so major smartphone manufacturers are actively applying UWB technology. Ranging methods using UWB are generally classified into two-way ranging (TWR) and one-way ranging (OWR). The OWR method has the advantage of simplicity, but has the constraint that the time synchronization between UWB devices must be precisely maintained for high accuracy. To overcome these limitations, in this paper, we propose an innovative OWR-based positioning technique enabling precise location estimation under the condition that UWB anchor nodes are not time-synchronized, by estimating and calibrating the time-asynchrony between UWB anchor nodes using Kalman filter. Also, we validate the positioning performance of the proposed method through simulation and confirm that it can achieve similar performance with an acceptable error range as in an ideal scenario where all devices are synchronized.

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