A Physical-Layer Secure Coding Scheme for Indoor Visible Light Communication Based on Polar Codes

Abstract

Visible light communication (VLC) can provide short-range optical wireless communication together with illumination using LED lightings. Since VLC channel is an open wireless channel, physical-layer security is desirable in order to hide secret information from unauthorized receivers, without reliance on upper-layer cryptographic techniques. In this paper, a secure coding scheme based on polar codes is proposed to simultaneously achieve physical-layer security and transmission reliability for indoor VLC systems under Wyner's wiretap model. An indoor VLC degraded wiretap channel model and an indoor VLC undegraded wiretap model are analyzed to estimate the corresponding secrecy capacity with typical indoor VLC scenarios considering the requirements of illumination and reliable transmission. Then, a physical-layer secure coding scheme and an enhanced scheme are designed to provide securely reliable communication without sacrificing the illumination functionality. Numerical results show that for VLC degraded wiretap channel, the proposed coding scheme can reduce the bit error rate (BER) of main channel to nearly 0 and increase that of wiretap channel to 0.5. Therefore, the mutual information between the sender and the eavesdropper and the BER of the legitimate receiver are both decreased to nearly 0. Both the security and reliability of VLC are guaranteed by the proposed coding scheme. And the practical secrecy rate reaches 85.96% at some positions when codeword length is 2 048 bits. Furthermore, an enhanced coding scheme with a feedback channel is proposed to handle the case that the wiretap channel is not degraded with respect to the main channel. With the feedback channel, the wiretap channel can be equivalently degraded and the security can IEEE Photonics Journal Physical-Layer Secure Coding Scheme for Indoor VLC be increased gradually with the increment of the degradation level of the wiretap channel. Meanwhile, the secrecy capacities can be asymptotically achieved for indoor VLC systems.

An enhanced indoor visible light communication physical‐layer security scheme for 5G networks: Survey, security challenges, and channel analysis secrecy performance

“…To simulate a multiuser VLC system, we will consider both rooms with the downlink scenario in a 3‐D space that has the legitimate channel in the existence of eavesdroppers. Since reflected signals are weaker compared to the LOS signal, 51 a simplified model will consider the LOS component only, using the parameters in Table 3.…”

Physical-Layer Security for Mobile Users in NOMA-Enabled Visible Light Communication Networks

“…Over the past five years, research on PLS for VLC networks has also attracted great interest. Signal processing technologies such as beamforming [16,17], precoding [18,19], artificial optical jamming [20] and polar-code-based secure coding [21] are used to improve the secrecy performance of VLC. Taking the adopted mathematical tools into account, stochastic geometry theory was used to derive the average secrecy capacity of system while the users were randomly distributed in the room [22].…”

Dynamic Physical-Layer Secured Link in a Mobile MIMO VLC System

“…Therefore, the distribution of these identified values of each pixel in the image plane is represented by the Gaussians mixture, henceforth the coming pixel, either to be characterized by one of the leading components of the model or, to considered as a foreground prior to updating the model [21]. These operations have applied to obtain the receiver, where the 1st frame is to initiate the MOG process, subsequently, to read the coming frame in order to define the history of pixel as highlighted in (11), hence, estimate the location of the receiver (foreground detection) using (12) as given in Fig. 4.…”

“…In [9], [11] a static-secured multiple-input, single-output (MISO) VLC channel is proposed based on the physical layer, whereas [10] focused on combining the real-valued channel-state information (CSI) with chaotic sequences to further improve the physical layer security of the VLC system. In [12], a secure coding scheme based on polar codes was proposed for SISO and MISO VLC to achieve physical-layer security for indoor VLC systems under Wyner's wiretap model, which ensures that the wiretap channel is not affected with respect to the main channel.…”