Analysis of Spread-Spectrum Algorithms to Prevent Jamming Attacks in Safety-Critical Applications

Rapid development in the field of wireless technologies makes the wireless systems feasible for high-data-rate and power-efficient applications. As one of the applications, wireless sensor and actuator networks have an expanding application field. In field of aeronautics, the substitute of cable-based sensory and actuator network by wireless technologies in aircraft is a novel approach, which aims to reduce the cable weight and enhance system functionalities, ease of layout and maintenance. However, the replacement of wired sensor networks with wireless systems raises several problems in terms of safety and reliability. During wireless data-transmission of sensory and actuator information in aircraft, the transmission channel is shared with several applications and encounter various types of noise and interference. This shared wireless transmission medium requires regulations and robust methods to fulfill the safety and reliability requirements. One of the significant threats in such a propagation medium is jamming attacks. Therefore, jamming-resistant wireless communication methods are examined in this work, specifically for safety-critical applications in aircraft. The proposed solution is spread-spectrum methods, which expand the signal in frequency domain to obtain a wider bandwidth. These methods are commonly used in wireless military and commercial applications, such as IEEE 802.15.4 standards for wireless personal area networks and IEEE 802.11b for Wi-Fi, to counter against jamming attacks and overcome interferences in a transmission channel. In this paper, we examine the anti-jamming performance of a type of spread-spectrum technique: Frequency-Hopping Spread-Spectrum (FHSS). To analyze the performance of FHSS against jamming attacks in terms of safety and reliability, we develop a transceiver on a real-time platform, which is based on a Xilinx Virtex-6 FPGA. We use Xilinx System Generator libraries to develop a Software-Defined Radio (SDR) in Simulink environment. This provides high-level and prompt DSP development capabilities. Furthermore, we model several jammer characteristics: tone, multitone, narrowband, partial-band and broadband jammers. Multitone and partial-band jammers are classified as worst-case jammers. By using these jammer models, we further simulate the data-link under worst-case jamming attack and test the performance of FHSS regardless of baseband modulation and error- correction algorithms