*Article* **Tracking Multiple Marine Ships via Multiple Sensors with Unknown Backgrounds**

**Cong-Thanh Do 1,\*,†, Tran Thien Dat Nguyen <sup>1</sup> and Weifeng Liu <sup>2</sup>**


Received: 23 September 2019; Accepted: 15 November 2019; Published: 18 November 2019

**Abstract:** In multitarget tracking, knowledge of the backgrounds plays a crucial role in the accuracy of the tracker. Clutter and detection probability are the two essential background parameters which are usually assumed to be known constants although they are, in fact, unknown and time varying. Incorrect values of these parameters lead to a degraded or biased performance of the tracking algorithms. This paper proposes a method for online tracking multiple targets using multiple sensors which jointly adapts to the unknown clutter rate and the probability of detection. An effective filter is developed from parallel estimation of these parameters and then feeding them into the state-of-the-art generalized labeled multi-Bernoulli filter. Provided that the fluctuation of these unknown backgrounds is slowly-varying in comparison to the rate of measurement-update data, the validity of the proposed method is demonstrated via numerical study using multistatic Doppler data.

**Keywords:** random finite sets; unknown background; bootstrapping method; GLMB filter; multisensor multitarget tracking; Murty's algorithm
