Aerospace and Electronic Systems Magazine March 2018 - 22

Feature Article:

DOI. No. 10.1109/MAES.2018.170023

Target Monitoring Using Small-Aperture Compact
High-Frequency Surface Wave Radar
Yonggang Ji, Jie Zhang, Yiming Wang, First Institute of Oceanography State Oceanic
Administration, Qingdao, China
Weifeng Sun, China University of Petroleum, Qingdao, China
Ming Li, Ocean University of China, Qingdao, China

INTRODUCTION
High-frequency surface wave radar (HFSWR) can detect and continuously track vessels beyond the horizon in excess of 200 nautical miles from the array [1]-[3]. Moreover, multiple HFSWRs
can be used, and their detection results can be fused to improve
the detection performance of marine target [13]-[15]. Most current
HFSWRs for ship surveillance are large phased-array systems. The
antenna arrays of such systems are hundreds or even thousands of
meters wide [4], [5], [15]. Some of those radar systems require
large fixed seaside radar sites or large transmit power. For those
reasons, large-array HFSWR has not been widely applied.
Recently, system miniaturization has become a trend in HFSWR technology, in which miniaturization of the antenna aperture
is more important than miniaturization of the equipment. Herein,
HFSWR with a small aperture is defined as compact HFSWR and
includes a small array and portable equipment. Compared with
large-array HFSWR, compact HFSWR occupies a smaller radar
Authors' current addresses: Y. Ji, Y. Wang, Laboratory of Marine
Physics and Remote Sensing, First Institute of Oceanography
State Oceanic Administration, No. 6 Xianxialing Road, Room
641, Qingdao 266061, China, E-mail: (jiyonggang@fio.org.
cn). J. Zhang, First Institute of Oceanography State Oceanic
Administration, No. 6 Xianxialing Road, Room 635, Qingdao
266061, China. W. Sun, College of Information and Control
Engineering, China University of Petroleum, No. 66 Changjiang West Road, Huangdao District, Qingdao 266580, China.
M. Li, College of Engineering, Ocean University of China, No.
238 Songling Road, Box 110, Qingdao 266100, China.
Manuscript received January 22, 2017, revised July 11, 2017,
and ready for publication September 13, 2017.
Review handled by D. O'Hagan.
0885/8985/18/$26.00 © 2018 IEEE

site, has lower power consumption, and is easier to deploy and
maintain. Compact HFSWR can, therefore, save scarce coastline
resources and can be installed on islands or offshore platforms.
Thus, applications of compact HFSWR can be further expanded.
Figure 1 shows the traditional processing scheme of detection
before tracking with single-station HFSWR. At each processing
stage, many methods can be used [2], [3]. In the traditional processing scheme, target detection and direction-of-arrival (DOA)
estimation are performed before target tracking. Because of the
reduction of the radar aperture, the beam width increases and the
direction-finding precision decreases, making this unsuitable for
compact HFSWR. Wider beam width leads to a decrease in the
signal-to-noise ratio (SNR) of a target at a given beam angle after
beam-forming, resulting in a lower detection rate and an increased
miss rate at the constant false-alarm rate (CFAR) detection stage.
If a target has not been detected for several consecutive measurements, it is impossible for HFSWR to track it. Moreover, the lower
direction-finding precision makes point association more difficult during tracking, potentially leading to breakage or loss of the
tracked target. Both of these factors affect the final target tracking
results and worsen the target-monitoring performance of HFSWR.
To date, most research on compact HFSWR has focused on
antenna miniaturization [6] or front-end signal processing of new
system radars, such as multiple-input, multiple-output (MIMO)
radar [7]-[9]. The main purpose of antenna miniaturization is to
reduce the size and weight of the antenna device; however, this
does not mean the smaller antenna aperture cannot improve the
detection performance of the radar system. Since 2000, there have
been many studies on target monitoring with compact HFSWR
with a portable antenna. Rutgers University has begun using the
SeaSonde HF Radar coastal ocean current and wave-monitoring
network for vessel detection purposes [10], [11]. There are some
restrictions for compact HFSWR with a portable cross-loop an-

Figure 1.

Traditional processing scheme of detection before tracking with single-station HFSWR.

IEEE A&E SYSTEMS MAGAZINE

MARCH 2018

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