## 1 Introduction
In [21], the authors consider the multiple jammers scenario in which multiple jammers can attack the network at the same time to achieve a better jamming effect. They propose the jamming detection scheme by developing X-rayed jammed-area localization algorithm. However, measurement data collection and position information sharing will bring more challenges. In [22], the authors investigate the multi-hop multi-channel cognitive radio network in the presence of multiple jammers. To deal with the energy-constrained problem, two novel algorithms are proposed to maximize the energy efficiency of data transmission from the source to the destination under the jamming attacks. Although the simulation results can verify the effectiveness of the proposed scheme, the applicable metrics may be limited due to the high overheads and algorithm complexity when the number of intermediate relays in the network is large. The digital feedback scheme is proposed to improve the speed of transceivers and it is also proved to be robust to noise in the feedback channel [23]. In order to deal with the energy-constrained issue and resource scarcity, the authors developed the joint controller and the related supporting access protocol to maximize both the energy and bandwidth efficiency of the vehicular access network, which is guaranteed to be reliable and safe in the wireless communication [24]. Recently, energy harvesting has become one of the appealing techniques for solving the energy-constraint problem in wireless networks. Practically, user equipment units (UEs) often are equipped with a limited-capacity battery. That results in degradation of network performance due to limited energy for the operation. Thus, energy harvesting technique can provide permanent energy for the battery without any physical replacements. Fortunately, UEs can harvest energy from non-radio frequency (RF) signals (e.g., solar, wind, heat, etc.) [25] or from RF signals [26; 27], which are available in ambient environments. In this paper, we consider the jamming attack scenario in cooperative communication system that consists of a source, a destination, a relay, and a jammer where the jammer intends to inject interference signals to block the transmission link (from the source to destination). The jammer in this paper is assumed to always broadcast enough the interference (_power_) to block the communication in its communication range when it is actived. We define the jammer as \"absolute jammer\". The behavior of the jammer is assumed to follow the Markov chain model. In order to deal with the challenge of the jammer, we propose to use a relay to help the source to forward the data to the destination. However, the relay is assumed to be a small and movable device (for easy set up). Subsequently, the relay has a small battery that can allow the device to work in a limited time. The energy harvesting technique is applied to deal with energy-constrained problem at the relay; however, the limited energy arrival rate is also taken into account where the relay can harvest non-RF energy from the ambient environment with a limited amount of energy in each time slot [22; 25]. Moreover, the imperfection of the spectrum sensing mechanism [20; 21; 28] on the jamming detection at the source is also considered. This paper aims to maximize the long-term achievable throughput of the cooperative communication system in which the source will make the optimal decision on whether or not the source should cooperate with the relay to transmit the data to the destination securely with the purpose of degrading the jamming effect. We formulate the problem based on the POMDP framework [28] and propose a novel scheme to obtain the optimal policy such that the source can select the best action in every single time slot by considering long-term throughput maximization.