Fast joint estimation for time delay and angle of arrival based on smooth preprocessing with orthogonal frequency division multiplexing

Abstract

In order to solve the problems of high complexity and absence of adaptability with the joint estimation for time delay (TD) and angle of arrival (AOA) in coherent multipath environments, a fast estimation algorithm based on orthogonal frequency division multiplexing (OFDM) technique is proposed. First, we combine OFDM signal characteristics with array features to obtain extended arrays. Then, we obtain the channel frequency domain response covariance matrices for TD and AOA estimation separately by smoothing preprocessing in the spatial and frequency domains, respectively. Finally, we estimate the TD values by a one‐dimensional (1‐D) spectral peak search, as well as determine the closed‐form solution for AOA by Unitary‐ESPRIT. In comparison with previous work, the proposed algorithm not only improves the adaptability in correlated or mixed multipath environments but also significantly reduces the complexity. The simulation results show the effectiveness and robustness of the proposed joint estimation algorithm.

Joint Estimation for Time Delay and Direction of Arrival in Reconfigurable Intelligent Surface with OFDM

“…In this part, we analyze the complexity of the proposed algorithm under the Coded-Response model and compare it with the 3D spectral peak search method (3D-MUSIC). To analyze the accuracy in the next section, we also compare the complexity of the algorithm (joint-smooth) employing smoothing preprocessing [22], which reduces the dimensions of the joint estimation model.…”

“…(iv) Compared with the existing RIS-and OFDM-based localization algorithms [23,24], the proposed algorithm can obtain the required parameters for localization based on a single station node in a coherent environment. Simulation results show that the proposed algorithm avoids the aperture loss of current smoothing algorithms [22,25] when processing coherent signals and thus has more advantages in terms of estimation accuracy.…”

“…For the coherent signal estimation, an approach [20] employing cyclostationary signals and a method [21] for separating coherent signal components have been proposed, both of which lead to more complex systems that are hard to implement in a joint estimation model. In addition, the method in [22] applies smoothing preprocessing to joint estimation to improve the adaptability in a coherent environment. However, smoothing preprocessing results in aperture loss and limited estimation accuracy.…”

Channel Charting with Angle-Delay-Power-Profile Features and Earth-Mover Distance

“…With a large antenna array and a wide bandwidth, a BS can acquire higher multipath resolution in the angle and delay domains [1]. Several papers have considered joint estimation of delay, angle of arrival, and receive power for complex multipath environments [2], [3].…”