Direct Position Determination of Noncircular Sources with Multiple Nested Arrays: Reduced Dimension Subspace Data Fusion

Abstract

Direct position determination (DPD) of noncircular (NC) sources with multiple nested arrays (NA) is investigated in this paper. Noncircular sources are used to expand the dimension of the received signal matrix, so the number of identifiable information sources and the accuracy of direct position determination are improved. Furthermore, nested array increases spatial degree of freedom. In this paper, the high-dimensional search problem of noncircular sources is investigated. Therefore, we propose algorithm dimension reduction subspace data fusion (RD-SDF) to reduce complexity and increase positioning accuracy. Simulation results show that the proposed RD-SDF algorithm for multiple nested arrays with noncircular sources has improved positioning accuracy with higher spatial degree of freedom than SDF, Capon, and two-step algorithms with uniform linear array and circular sources (CS).

Direct Position Determination of Noncircular Sources with Multiple Nested Arrays via Weighted Subspace Data Fusion

“…In Figure 4, for successive difference co-array DCA, we divide DCA into R 1 + 1 equivalent subarrays, which has R 1 + 1 elements each. e corresponding received signal can be indicated as follows [9]:…”

“…. , R 1 + 1) subarray, 􏽥 u i means the vector that the ith element value is 1, and the other element values are all 0 [9].…”

“…] means the orientation matrix of SS-DCA, and its qth orientation vector can be indicated as follows [9]:…”

“…e core idea is to directly obtain the position information of the target from the original sampling signal without estimating the intermediate observation value. is principle avoids the problem of data association [7][8][9][10]. erefore, direct positioning method has higher estimation accuracy and resolution [11][12][13][14].…”

Real-Valued Direct Position Determination of Quasi-Stationary Signals for Nested Arrays: Khatri–Rao Subspace and Unitary Transformation

“…An improved SDF DPD algorithm for NC signals was proposed in [20], and its complexity was reduced by devising a Newton-type iterative method. Hereafter, some sparse arrays, such as nested array (NA) [21] and coprime array [22], were employed to obtain a larger array aperture, higher degrees of freedom (DOF), and higher accuracy [23][24][25]. In addition to the OFDM and NC signals, the properties of cyclo-stationary signals [26] can also be considered in the DPD algorithm.…”