Multipath Generalized Labeled Multi-Bernoulli Filter
Bin Yang, Jun Wang, Wenguang Wang, and Shaoming Wei
School of Electronic and Information Engineering, Beihang University, Beijing, China
Email:young
being@126.com
Abstract—Traditional multitarget tracking algorithms assume
that each target can generate at most one detection per scan.
However, in the over-the-horizon radar (OTHR), a target may
produce multiple detections because of multipath propagation.
In this paper, we propose a new algorithm, called multipath gen-
eralized labeled multi-Bernoulli (MP-GLMB) filter, to effectively
track multiple targets in such multiple-detection systems. The
proposed technique is based on the labeled random finite set
(RFS), which estimates the number of targets and the trajectories
of their states. The proposed MP-GLMB filter is compared with
the multipath version of the probability hypothesis density (PHD)
filter and the multi-target multi-Bernoulli (MeMber) filter, and
simulation results show that our algorithm has improved tracking
performance.
I. INTRODUCTION
Multitarget tracking problem involves estimating an un-
known and time-varying number of targets and their corre-
sponding trajectories by using measurements from sensors.
Three major algorithms, namely, the Multiple Hypothesis
Tracker (MHT), the Joint Probabilistic Data Association Fil-
ter (JPDAF) and algorithms based on the random finite set
(RFS) theory have been proposed to deal with problems in
multitarget tracking, such as nonunity probability of detection,
presence of spurious measurements (clutter), and uncertainty
of measurement-target association [1], [2], [3], [4], [5].
In these algorithms, a common assumption is that one target
produces at most one measurement in every scan, which is
valid in single-detection systems. However, in many practical
scenarios, one target can generate more than one detection
per scan. A well-known example of such a system is the
over-the-horizon radar (OTHR) [23], [24], [25], [26], which
radar signals from the same target are propagated by multiple
paths (MPs) due to multiple ionospheric layers. These multiple
detections (MDs) in receiver of OTHR bring benefit and
disadvantage to the tracking algorithms simultaneously. If the
MDs from multipath propagation can be exploited effectively,
the performance of the tracking algorithm will be improved
greatly. But the tracking with MDs needs to solve not only
measurement-target association, but also measurement-path
association, which requires complex algorithm. Based on the
JPDA framework [8] and the MHT framework [9], MD-JPDA
filter [29] and MD-MHT algorithm [28] were proposed, re-
spectively, to tracking multiple targets with multiple detections
in OTHR. Since the RFS approach, such as the probability
hypothesis density (PHD) filter [10], [14] and the multi-target
multi-Bernoulli (MeMber) filter [5], [12], can avoid the data
association, the MD-PHD filter [31] and the MP-CBMeMBer
filter [32] have been proposed as tractable Bayesian filters with
low complexity in OTHR.
However, these RFS-based filters only estimate target states
at individual time instants and not provide target trajectories.
In order to overcome this limitation, [15], [16] appended an
unique label to RFS, which called labeled RFS, and linked
the target states with the same label at different scan to form
the trajectory of targets. Since the generalized labeled multi-
Bernoulli (GLMB) RFS is conjugate prior to the multitarget
point measurement model, the GLMB filter and the δ-GLMB
filter have been proposed as tractable Bayesian multitarget
trackers.
In this paper, we develop a GLMB filter, which called MP-
GLMB filter, for multipath multitarget tracking. First, we de-
rive the likelihood function of the multipath observation model.
Then, we provide the recursion of the GLMB density with
multipath observation likelihood inspired by the GLMB filter
for extended target tracking [33], which is another multiple
detection tracking problem. Furthermore, we propose a joint
prediction/update formulation [18] of the MP-GLMB filter and
implement it by using Murty’s algorithm [20], [21].
The rest of the paper is organized as follows. In Section II,
we present the problem description of the multipath system and
the background on labeled RFS filtering. The derivation and
implementation of the MP-GLMB are provided in Section III.
Simulation results are given in Section IV. Finally, in Section
V, conclusions are discussed.
II. P
ROBLEM DESCRIPTION AND BACKGROUND
In this section we provide the mathematical preliminaries
of the multipath multitarget tracking problem in OTHR. We
also briefly review the background of the labeled RFS.
A. Multipath System
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7DUJHW
Fig. 1: OTHR multipath propagation modes.
The OTHR can detect targets beyond the horizon by using
internal reflection of high frequency radio waves through the
ionospheric layer. There are two major ionospheric layers E
and F scatter the radar signal from transmitter to targets and
2018 21st International Conference on Information Fusion (FUSION)
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