ELECTRONIC ATTACK USING SDR

Cyber is concerned with networks of systems in all their possible forms. Electronic warfare (EW) is focused on the many different uses of the electromagnetic spectrum (EMS). Given that many networks make use of the EMS (wireless networks), there is clearly large scope for collaboration between the cyber-warfare and EW communities. Unfortunately, such collaboration is complicated by the significant differences between these two realms. Software-defined radio (SDR) systems are based on interfaces between the EMS and computers and thus offer tremendous potential for encouraging cyber-EW collaboration. The concept of SDR is reviewed along with some hardware and software SDR systems. These are then used to propose a number of projects where SDR systems allow collaboration between the cyber and EW realms to achieve effects which neither realm could achieve alone.

The article discusses some of the technologies that ensure the autonomy of unmanned aerial vehicles (UAVs) on the battlefield, methods of increasing the efficiency of UAV communication channels in the context of electronic warfare (EW). The author analyzes the threats to autonomous UAVs that may arise from the use of electronic warfare, and also presents the characteristics of one of the typical modern electronic warfare complexes. This article discusses the development of a test model of a wireless data transmission channel designed to develop technologies for countering electronic warfare and traininga neural network. The use of this model will allow the development of original domestic algorithms for countering enemy electronic warfare. The requirements of manufacturers to the electronic equipment of autonomous UAVs are analyzed. The possibility of using non-professional SDR radio equipment and open source software and hardware platforms for the develop-ment and verification of these countermeasures algorithms is considered. The algorithm for changing data transmission pa-rameters in the event of interference is determined. The choice of the type of neural network for use in the cognitive radio system of the UAV is substantiated. The idea of applying adaptive coding in UAV communication channels using multicompo-nent turbo codes in combination with neural networks that are simultaneously used for cognitive radio was further developed. Using information from the neural network about subsequent changes in the communication channel will reduce the adaptation time of the coding system, which will reduce the number of errors in data transmission and increase the reliability of commu-nication, especially when using dynamic spectrum access.The article is devoted to the problems of creating methods and models that use software-defined radio (SDR), cognitive radio, and multi-level parametric adaptation of turbo-code structures using artificial intelligence to improve the efficiency of wireless data transmission systems in the context of active use of electronic warfare by ensuring the reliability of information

The purpose of this article is to present simple relations that allow one to find the upper bound on the phase noise of a phase-locked oscillator (PLO), its frequency stability, mean-square incidental phase noise modulation (Φ <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) and phase jitter. Simple closed-form equations are derived that are not intend ed as design tools, but are intended to establish upper limit specifications for the phase noise levels of PLOs used in wideband electronic attack (EA) and electronic warfare (EW) systems. A block diagram of a hypothetical system is used to illustrate how an EA system is susceptible to degradation due to phase noise of PLOs. This part presents a technique to model the phase noise spectral density of a manufacturer's PLO. Based on the manufacturer's specifications, the model allows the prediction of the total phase noise, phase jitter and predicted frequency uncertainty (Allan Variance) of the PLO considered. Part II (to appear in the February 2012 issue of IEEE Microwave Magazine) will present a technique to calculate the common-mode coupling of the oscillator phase noise into the following intermedi ate frequency (IF) section of a mixer. The coupled noise may increase the noise figure of a receiver. A method to estimate the increase in phase noise due to vibration will also be presented. Some basic definitions and performance characteristics are described in "Performance Metrics for Electronic Warfare Receivers".

As Electronic Warfare (EW) relevant technologies develops, more complex and solid defense algorithm is required to keep the military secrets and message in safe. In the wireless communication system, Low Probability of Interception (LPI) communication algorithms, based on Code Division Multiple Access (CDMA), had been introduced to keep the message safe. Frequency Hopping CDMA (FH-CDMA) and Direct Sequence CDMA (DS-CDMA) are the representative methods of the LPI communication algorithm. FH-CDMA is widely used; however, the system has an expensive hardware configuration requirement due to the implementation complexity. In addition, several studies presented improved LPI communication algorithms with a physical-layer level processing; however, they have limitations of unable to well-hide the original signal. To address these problems, we propose an algorithm, called noise communication, which generates Gaussian distributed random numbers that added to In-phase and Quadrature (I/Q) input data independently to hide the original signal. Through Matlab simulation, we compare the conventional DS-CDMA and the proposed algorithm applied DS-CDMA and evaluate the effect of the algorithm with different configurations of PN sequence length and the effective level of the algorithm. Through the evaluations, we observe the algorithm can provide Signal-to-Noise Ratio (SNR) gain than the conventional DS-CDMA and SNR gain has an inverse relationship with system stability. Moreover, we exploit a Software Defined Radios (SDR) hardware to implement the algorithm for the demonstration of a noise-shaped Radio Frequency (RF) signal.

This paper presents Sora, a fully programmable software radio platform on commodity PC architectures. Sora combines the performance and fidelity of hardware software-defined radio (SDR) platforms with the programmability and flexibility of general-purpose processor (GPP) SDR platforms. Sora uses both hardware and software techniques to address the challenges of using PC architectures for high-speed SDR. The Sora hardware components consist of a radio front-end for reception and transmission, and a radio control board for high-throughput, low-latency data transfer between radio and host memories. Sora makes extensive use of features of contemporary processor architectures to accelerate wireless protocol processing and satisfy protocol timing requirements, including using dedicated CPU cores, large low-latency caches to store lookup tables, and SIMD processor extensions for highly efficient physical layer processing on GPPs. Using the Sora platform, we have developed a few demonstration wireless systems, including SoftWiFi, an 802.11a/b/g implementation that seamlessly interoperates with commercial 802.11 NICs at all modulation rates, and SoftLTE, a 3GPP LTE uplink PHY implementation that supports up to 43.8Mbps data rate.

As wireless platforms converge to multimedia systems, architectures must converge to support voice, data, and video applications. From a processor architecture perspective, support for signal processing (both audio and video), control code, and Java execution will be required in a convergent device. Traditionally, wireless communications systems have been implemented in hardware. Convergent devices must be able to roam seamlessly across multiple communications systems. To avoid excessive hardware costs, a Software Defined Radio (SDR) approach offers a programmable and dynamically reconfigurable method of reusing hardware to implement physical layer processing. In this paper, we discuss trends in wireless platforms which are inherently convergence platforms. We also present the Sandbridge state-of-the-art example platform that supports both communications and multimedia applications processing. The architecture efficiently executes Java, Digital Signal Processing (DSP), and control code. Architectural features that reduce power dissipation and enable real-time processing are described. All of the communications and multimedia processing is executed completely in software without specialized hardware support. The processor is programmed in C with supercomputer-class compiler support for automatic vectorization, multithreading, and DSP semantic analysis.

While cyberspace is emerging as a new battlefield, conventional Electronic Warfare (EW) methods and applications are likely to change. Cyber Electronic Warfare (CEW) concept which merges cyberspace capabilities with traditional EW methods, is a new and enhanced form of the electronic attack. In this study, cyberspace domain of the battlefield is emphazised and the feasibility of integrating Cyber Warfare (CW) concept into EW measures is researched. The SWOT (Strengths, Weaknesses, Opportunities and Threats) analysis method is used to state the operational advantages of using CEW concept in the battlefield. The operational advantages of CEW are assessed by means of its effects on adversary air defense systems, communication networks and information systems. Outstanding technological and operational difficulties are pointed out as well. As a result, a comparison of CEW concept and conventional EW applications is presented. It is concluded that, utilization of CEW concept is feasible at the battlefield and it may yield important operational advantages. Even though the computers of developed military systems are less complex than normal computers, they are not subjected to cyber threats since they are closed systems. This concept intends to show that these closed systems are also open to the cyber threats. As a result of the SWOT analysis, CEW concept provides Air Forces to be used in cyber operations effectively. On the other hand, since its Collateral Damage Criteria (CDC) is low, the usage of cyber electronic attack systems seems to grow up.

Software-defined radio (SDR) devices have significantly advanced communication networks by reducing the cost and development time of radio frequency (RF) designs. Their programmability enhances system capabilities, making them valuable for both research and application-driven tasks. With the growth of the Internet of Things (IoT), the need to validate, process, and decode numerous incoming signals has increased - an area where SDRs are highly effective. This paper explores the integration of surface acoustic wave (SAW) devices and SDRs for wireless, in situ sensor response measurements. SAW devices are employed for time delay analysis, while SDRs capture signal data across the 218-230 MHz range using 1921 samples. The inverse Fourier transform is applied to convert frequency-domain data to the time domain. Signal quality is evaluated against measurements from a commercial vector network analyser (VNA). Using a LimeSDR Mini, achieves reliable time delay detection with results closely matching those of the VNA.

At first glance most radios appear to be single function—a first-generation cellular phone sends your voice, while a WiFi base station connects you to the Internet. Upon closer inspection, both of these devices are actually quite flexible and support different waveforms. Looking at all the radio devices in my house, only the garage door opener and the car key fob seem to be truly fixed. With this introduction, clearly a software-defined radio’s main characteristic is its ability to support different waveforms.

Software Defined Radio (SDR) devices are becoming increasingly popular due to their support for mode-, standardand application-flexibility. At the same time however, the energy consumption of such devices typically suffers from the use of reconfigurable real-time platforms which are known to be severely power hungry. In this work we therefore show how to use tools and techniques developed by the formal methods community to minimize the energy consumption of Finite Impulse Response (FIR) filters which are extensively used in SDR front-ends. We conduct experiments with four different FIR filter structures where we initially derive data flow graphs and precedence graphs using the Synchronous Data Flow (SDF) notation. Based on actual measurements on the Altera Cyclone IV FPGA, we derive power and timing estimates for addition and multiplication, including idling power consumption. We next model the FIR structures in UPPAAL CORA and employ model checking to find energyoptimal solutions in linearly priced timed automata. In conclusion we state that there are significant energy-versus-time differences between the four structures when we experiment with varying numbers of adders and multipliers. Similarly, we find that idle power becomes an important parameter when a high number of functional units are allocated.

Real-time monitoring is an essential part in the development of healthcare monitoring systems. Research has shown that human movement affects the propagation of radio frequencies, as signals will reflect off the human body. Machine Learning techniques have been used in research to classify patterns observed in the signal propagation. This paper makes use of universal software radio peripheral devices to create a wireless communication link where the signal propagation data, known as channel state information, is collected while a user moves or remains still. A machine learning model which achieved an accuracy result of 93.25 % is used to classify between movement and no activity. Inference is then used to decide if the human position is sitting or standing and detected movements are used to differentiate between the two positions. The testbed implements cloud storage and a web-interface to present a visualisation of the human position.

This paper deals with the design of non-coherent jamming strategies capable of ensuring spectral compatibility with friendly radio frequency (RF) emitters. The goal is achieved via a cognitive approach, which, after recognizing the presence of friendly RF systems within the bandwidth of interest (perception), synthesizes a jamming waveform (action) with spectral notches, that allows to interfere exclusively with opposite emissions. Two methods are proposed for the synthesis of the jamming signal. The former leverages optimization techniques for quadratically constrained quadratic problems (QCQP) where each constraint embeds the interference level tolerable by a specific friendly RF system. The latter is a very computationally efficient approach based on simple projections, allowing a control over the spectral notch positions and widths. At the analysis stage, the performance of the devised jamming techniques is firstly numerically analyzed in terms of spectral occupancy and autocorrelation characteristics. The impact of the quantization process involved in the digital-to-analog conversion (DAC) of the jamming waveforms is also examined, with a particular focus on the spectral shaping impairments resulting from reduced DAC resolution. Finally, waveform transmission and reception is experimentally assessed with software defined radio (SDR) devices.

A Fractional Fourier Transform (FrFT) based waveform design for joint radar-communication systems (Co-Radar) that embeds data into chirp sub-carriers with different time-frequency rates has been recently presented. Simulations demonstrated the possibility to reach data rates as high as 3.660 Mb/s while maintaining good radar performance compared to a Linear Frequency Modulated (LFM) pulse that occupies the same bandwidth. In this paper the experimental validation of the concept is presented. The system is considered in its basic configuration, with a mono-static radar that generates the waveforms and performs basic radar tasks, and a communication receiver in charge of the pulse demodulation. The entire network is implemented on a Software Defined Radio (SDR) device. The system is then used to acquire data and assess radar and communication capabilities.

The advent of the software defined radio (SDR) concept has offered a new paradigm for the modem designer. Consider the requirements of implementing a MIL-STD-188 UHF DAMA modem in a CORBA-based software environment. Here direct access to the hardware is denied. Interfaces to the synthesizer and AGC functions are wrapped in CORBA-based calls. In addition, no hardware timing signals exist to help establish frame synchronization. These and others are the requirements that were successfully met in our implementation of the UHF SATCOM modem for the Digital Modular Radio (DMR) program. This CORBA-based software modern solution is not attached to any particular piece of modem hardware and, as such, is highly portable. This paper reveals the architectural features that allow the inherently slow CORBA-implementation to synchronize and respond to the real-time requirements of the DAMA network.

In this paper, we present an experimental evaluation of the performance benefits provided by flexible duplexing, an access technique that allows uplink and downlink cells to coexist within the same time-frequency resource blocks. In order to replicate a wireless multi-tier network composed of 1 macro-cell and 2 small cells, a measurement campaign has been conducted using an indoor wireless testbed comprised of a total of 6 multiple-input multiple-output (MIMO) software-defined radio (SDR) devices. Since each cell has a single active user, each uplink/downlink configuration can be identified with a different interference channel, over which interference alignment (IA) is used as an inter-cell interference management technique and compared to other existing methods. The obtained results show that flexible duplexing clearly outperforms the conventional time-division duplex (TDD) access approach, where all cells operate synchronized either in uplink or dowlink mode. Additionally, interference alignment consistently provides better results in most of the interference regimes when compared to minimum mean square error (MMSE)-based schemes. The impact of channel estimate quality on the different communication strategies is also studied. It is worth highlighting that the presented over-the-air (OTA) experiments represent the first implementation of IA with real-time precoding and decoding.