TOA and DOA Estimation for IR‐UWB Signals: An Efficient Algorithm by Improved Root‐MUSIC

Abstract

The automatically paired time of arrival (TOA) and direction of arrival (DOA) can be jointly estimated via a high-precision multidimensional spectral peak search- (SPS-) based multiple signal classification (MUSIC) algorithm in the impulse radio ultrawideband (IR-UWB) positioning system, while heavy computational burden is required. To tackle this issue, we propose an improved root-MUSIC algorithm for joint TOA and DOA estimation. After modelling the frequency domain form of the received signal, the algorithm first uses the signal subspace to establish the relationship between the two antennas. Then, the MUSIC spatial spectrum function is reconstructed with this relation, which enables it to offer a spectrum function in regard to the one-dimensional (1D) parameter of time delay. For further reducing the complexity, the TOA estimates of one antenna are obtained via 1D polynomial root finding instead of SPS, and the TOA estimates of the other antenna can be calculated by the established relationship. Finally, the DOA estimation can be achieved with the estimated TOAs. Due to the relationship between two antennas with signal subspace, the parameters estimated by the proposed algorithm are autopaired. Numerical simulations substantiate the superiority of the proposed algorithm.

Low-Complexity Joint Angle of Arrival and Time of Arrival Estimation of Multipath Signal in UWB System

“…Meanwhile, a Root-MUSIC algorithm is proposed to reduce the computational complexity in [ 25 ]. In [ 26 ], the computational complexity is further reduced compared with [ 25 ], which requires a spatial-spectral search to estimate the TOA. Ref.…”

“…Ref. [ 26 ] estimates the TOA of two antennas using a polynomial root method, but the estimation accuracy is slightly reduced. Ref.…”

“…In [ 29 ], the AOA is firstly estimated by frequency domain waveforms, and the TOA is estimated from AOA. Unlike [ 23 , 24 , 25 , 26 , 27 , 28 ], its AOA accuracy is not affected by the TOA estimation accuracy, but its TOA estimation accuracy is unsatisfied. Refs.…”

“…Refs. [ 23 , 24 , 25 , 26 , 27 , 28 , 29 ] only consider dual antennas case, which does not consider the case of multiple antennas. In [ 30 ], the joint estimation of AOA and TOA is extended to three-dimensional space positioning using an iterative approach with high computational complexity, which is only applicable to the case of a single snapshot.…”

“…Although there are some works, e.g., refs. [ 23 , 24 , 25 , 26 , 27 , 28 , 29 ], considering the joint estimation of AOA and TOA in UWB system, only the data model of dual antennas is considered, which is not a general case. Meanwhile, the estimation accuracy and real-time performance of the methods in refs.…”