An Applied Method for Clustering Extended Targets With UHF Radar

Abstract

In this paper, the application of coherent ultra-high frequency (UHF) Doppler radar for ship target detection over river is investigated. Due to the wide beam and high resolution of UHF radar, ship target echoes are usually significantly extended in both the range and Doppler dimensions of the radar Range-Doppler (R-D) spectrum. The range and radial velocity of the extended target are difficult to be determined using a constant false alarm rate (CFAR) detector, especially for the low-radial-velocity case in which the detection performance of CFAR detector is deteriorated due to strong river clutter. To solve this problem, an applied clustering method is proposed to detect and classify multiple targets and obtain corresponding target centers from the CFAR outputs. The target extension characteristics, which are used for clustering, are modeled and employed in segments for different range. The effectiveness of the proposed method is validated using both simulated and field data and the clustering method can classify extended targets without the need of knowing the number of targets beforehand.INDEX TERMS UHF radar, extended target, target detection, constant false alarm rate (CFAR), clustering method.

Radar Technology for River Flow Monitoring: Assessment of the Current Status and Future Challenges

“…Compared with the fixed-point radar, the side-scan radar is typically set up on the bank, which has a wider monitoring distance, and can monitor the average flow velocity within a segmented range and identify the direction of the signal in space. However, the side-scan radar is still in the research and verification stage, and few applications are promoted [33][34][35]. The early studies of radar flow monitoring were mostly focused on experiments [36][37][38]; for example, Teague et al have successfully verified the possibility of using a radar current meter instead of traditional methods for surface velocity monitoring and flow calculation [39].…”

A radar extended target angle estimation method based on effective phase clustering

“…While the increase in resolution improves the ability to detect and track targets [2,3], it also leads to the phenomena of larger targets being scattered across multiple resolution units in the form of scatter points. Obviously, traditional point-like target angle measurement algorithms, which assume that targets only occupy a single resolution unit, cannot be directly applied to extended targets [4][5][6].…”

“…FIGURE6 Comparison results of the method of processing in this paper are compared with the ACA method processing: (a) interferometric phase statistics distribution, (b) DOA angle estimation method schematic, (c, d) compare the results of positioning on an electronic map. ACA, average complex amplitude; DOA, direction of arrival.…”

Direction-of-Arrival Angle and Position Estimation for Extended Targets Using Multichannel Airborne Radar Data

“…However, in high resolution data targets like ships usually appear as extended targets occupying more than a single resolution cell [6]. As a result, state-of-the-art DOA angle estimation methods, which are designed for point-like targets, cannot be applied directly to extended targets even if their corresponding pixel-based detections are already clustered [7]. An example is shown in Fig.…”