Interference Localization On-Board the Satellite Using Drift Induced Virtual Array

Abstract

Herein, we investigate the interference received from other wireless networks into a satellite communication (SATCOM) link, and review approaches to identify the interference location using on-board satellite processing. Interference is an increasing problem for satellite communication links, and while receiving signals from gateways or user terminals, the uplink is prone to disturbance by interference due to jammers or unintentional transmissions. In this paper, our aim is to localize unknown interference sources present on the ground by estimating direction of arrival (DOA) information using onboard processing (OBP) in the satellite, and the satellite drift inducing a virtual array. In this work, the signal sampled by the drifting single antenna feed is modeled as using an arbitrary array. Building on this model, we perform the 2-D DOA (azimuth and elevation) estimation. The key challenges in such a design include single snapshot based DOA estimation with low complexity and robustness, arising out of limited on-board computational complexity as well as uncertainty in parameters like the drift speed. Employing realistic satellite drift patterns, the paper illustrates the performance of the proposed technique highlighting the accuracy in localization under adverse environments. We provide numerical simulations to show the effectiveness of our methodology.

Cramer-Rao Bound on DOA Estimation of Finite Bandwidth Signals Using a Moving Sensor

“…DOA estimation using a single moving sensor is an interesting problem because of its applicability in diverse areas including speaker and underwater localization as well as interference localization using satellite drifts [1][2][3][4][5][6][7]. As a special case, satellite systems are interfered by unintentional/ malicious transmissions requiring rather precise localization on-board; the satellite drift offers a virtual array to solve this issue [7]. Further, the proliferation of sensing capabilities in a variety of devices (i.e.…”

“…In these arrangements, the received signal is assumed to be perfectly coherent throughout the sensor array. When the bandwidth of the source signal is quite large, such as in satellite (few MHz to GHz) [7], coherency across the array cannot be assumed. Further, such loss in coherency is a function of DOA and the signal bandwidth.…”