Analysis and Optimization of Wireless-Powered Cooperative Jamming for Sensor Network Over Nakagami-

Analysis and Optimization of Wireless-Powered Cooperative Jamming for Sensor Network Over Nakagami- m Fading Channels

Abstract: This letter studies the secrecy communication in a wireless powered sensor network, where the access-point (AP) firstly sends energy signal to power the sensor node (S) and jammer (J), then J exploits the harvested energy to send jamming signal to interfere the eavesdropper, in order to protect the uplink communication from S to the AP. Specifically, assuming that all channels are subjected to Nakagami-m fading, we derive a closed form expression of the exact secrecy outage probability (SOP). Furthermore, by exploiting the results about the approximations to the statistics of products of independent random variables, we provide the approximate and asymptotic expressions of the SOP, the latter enables us to obtain the secrecy diversity order (SDO), observe the impact of several parameters on the SOP and provide a closed-form expression for the time switching (TS) ratio which maximizes the secrecy throughput. Simulations present the accuracy of the derived SOP and SDO, the tightness of the approximation and the effectiveness of the obtained TS ratio.

Existing system:

This letter follows the works. In particular, the main contributions are given as: 1) We consider the practical Nakagami-m channels instead of Rayleigh channels due to the short transmission distance and derive the closed-form expression of the exact SOP; 2) We provide the tight approximation and the asymptotic expression of the SOP, the latter enables us to obtain the quite exact secrecy diversity order (SDO), observe the impact of several system parameters; 3) Compared to the energy-rich system, we prove that the EH operation causes a little impact on the SDO. Moreover, the impact would vanish as the shape parameter (m) increases; 4) based on the asymptotic SOP, we provide a solution for the time switching (TS) ratio which maximizes the secrecy throughput.

Proposed system: On the other hand, as the wireless medium owns the open characteristic, information leakage is always a challenge issue. To solve this problem, physical layer security (PLS), as an emerging technique, gives numerical powerful methods.

As required by multiple scenes, the studies about the combination of the EH and PLS techniques have became a popular topic. Specifically, considered a wireless powered wiretap scene, where a multi-antenna source (S) firstly harvests energy from the access-point (AP), then exploits the harvested energy to communicate with a legitimate node in the presence of a passive eavesdropper (E).

Advantages: Under the same scene, further studied the advantages of full-duplex-enabled relay on the average secrecy rates. This letter follows the works of. In particular, the main contributions are given as: We consider the practical Nakagami-m channels instead of Rayleigh channels due to the short transmission distance and derive the closed-form expression of the exact SOP. We provide the tight approximation and the asymptotic expression of the SOP, the latter enables us to obtain the quite exact secrecy diversity order (SDO), observe the impact of several system parameters; 3) Compared to the energy-rich system, we prove that the EH operation causes a little impact on the SDO. Disadvantages:

On the other hand, as the wireless medium owns the open characteristic, information leakage is always a challenge issue. To solve this problem, physical layer security (PLS), as an emerging technique, gives numerical powerful methods.

As required by multiple scenes, the studies about the combination of the EH and PLS techniques have became a popular topic.

Specifically, considered a wireless powered wiretap scene, where a multi-antenna source (S) firstly harvests energy from the access-point (AP), then exploits the harvested energy to communicate with a legitimate node in the presence of a passive eavesdropper (E).

Modules: Internet of things: WIRELESS sensor networks, as an important branch of the Internet of Things (IoT), generally consist of massive low-cost sensor nodes, the batteries of which are often small and hard to be replaced. Fortunately, radio frequency (RF) signal based energy harvesting (EH) technique provides a reliable and controlled way to solve this energy-constrained problem. On the other hand, as the wireless medium owns the open characteristic, information leakage is always a challenge issue. To solve this problem, physical layer security (PLS), as an emerging technique, gives numerical powerful methods. As required by multiple scenes, the studies about the combination of the EH and PLS techniques have became a popular topic.

Specifically, considered a wireless powered wiretap scene, where a multi-antenna source (S) firstly harvests energy from the access-point (AP), then exploits the harvested energy to communicate with a legitimate node in the presence of a passive eavesdropper (E).

Secrecy diversity order: Under the same scène, further studied the advantages of full-duplex-enabled relay on the average secrecy rates. This letter follows the works. In particular, the main contributions are given as: We consider the practical Nakagami-m channels instead of Rayleigh channels due to the short transmission distance and derive the closedform expression of the exact SOP; We provide the tight approximation and the asymptotic expression of the SOP, the latter enables us to obtain the quite exact

secrecy diversity order (SDO), observe the impact of several system parameters; 3) Compared to the energy-rich system, we prove that the EH operation causes a little impact on the SDO. Moreover, the impact would vanish as the shape parameter (m) increases; 4) based on the asymptotic SOP, we provide a solution for the time switching (TS) ratio which maximizes the secrecy throughput.

Transmission block: We consider the security performance of a EH based wireless sensor network, which consists of four nodes operated in half-duplex mode: the hybrid AP, S, J and E. All nodes are equipped with single antenna. In addition, it is assumed that E is in close proximity to S for pessimistic consideration. We adopt the well-known TS protocol for wireless energy transfer and data transmission. Hence, each transmission block (TB) is divided into two phases: in the first phase of time duration, the AP transmits energy signal to the energy-constrained S and J, and in the second phase of time duration, S transmits its data information to the AP and J sends jamming signal by exhausting their harvested energy in the first phase. We assume that the jamming signal is known at the AP, which means that the jamming interference can be eliminated at the AP .Without loss of generality; T is set to 1 in this letter.