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Summary: Communication systems are adopting all‐software architectures, because of their scalability, extensibility, flexibility, and cost‐effectiveness. This paper introduces a concurrent approach to the development and verification of baseband systems for satellite ground operations based on the behaviour‐driven development methodology. The open‐source GNU Radio development kit is used for developing the software‐defined radio baseband signal processing, as well as simulating the satellite and realistic channel impairments. The system performance at the end shows deviations of less than 1 dB with respect to the ideal performance and the Green Book standards specified by the Consultative Committee for Space Data Systems. [ABSTRACT FROM AUTHOR]

One of the important aspects in the study of wireless communication is channel modeling that is based on wave propagation theory and empirical measurements models. Most of the common undergraduate curricula address only theoretical aspects of wireless channels, while the related laboratory experiments concentrate on advanced digital modulation techniques and deal with topics such as pilot‐based channel estimation and equalization in orthogonal frequency division multiplexing modulation. In this paper, it is shown that some fundamental channel properties may be reproduced with laboratory experiments that require only a basic knowledge of communication principles, such as baseband and bandpass notation. These experiments can be carried out with affordable software‐defined radios, which have recently become extremely popular in the teaching of communication. Such experiments may enhance the teaching with hands‐on measurements of practical channels, while reinforcing the understanding of probability and random processes theory. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the effect of mobility on the performance of full-duplex radio. For this, we implement a full-duplex radio prototype using a software-defined radio that is powered by a battery and can thus function in mobile environments. In addition, we compare the performance of self-interference cancellation schemes for two cases considering multi-antenna based full duplex radio and circulator based full duplex radio, respectively. Finally, we show a negative effect of mobility on the self-interference cancellation performance of the full-duplex radio system, and analyze the effect of the update period of the self-interference cancellation filter on the performance. In particular, when the update period is reduced by about 1000 times, the power of self-interference is reduced by 5.7dB for circulator-based full-duplex radio and 3.1dB for both antenna-based full-duplex radio. [ABSTRACT FROM AUTHOR]

While traditional radio recordings are limited to individual broadcasts transmitted over a single channel, spectrum recordings capture all signals received by an antenna simultaneously, using software that allows users to navigate and play back captured channels. The Radio Spectrum Archive (RSA) has acquired and preserved recordings from the 1980s to present, which are now publicly available through an arrangement with the Internet Archive. Using the RSA as its case study, this paper provides a brief history of spectrum recording, delineates key differences between spectrum recordings and traditional radio recordings, and identifies technical, administrative, and procedural challenges impacting future preservation and access. [ABSTRACT FROM AUTHOR]

By exploiting the sparsity of the scene containing only a few moving targets, a high-resolution and real-time range-Doppler map generation algorithm for passive bistatic radar is proposed. The proposed algorithm divides the long integration time into multiple short batches, from which a few batches are randomly selected on the basis of compressive sensing theory. A one-dimensional cross correlation is performed for each selected batch to obtain the range-compressed profile. Mean-value subtraction is then performed to suppress the direct path interference and stationary target reflections. Finally, an extended orthogonal matching pursuit algorithm is proposed for the effective estimation of target Doppler frequency. Practical application of this novel algorithm is examined by the detection of airplanes and ships via two synchronized general-purpose software-defined radio receivers. The results show that the proposed algorithm can achieve an improved resolution and a reduced sidelobe level compared to the conventional algorithms. [ABSTRACT FROM AUTHOR]

• An islanding can be detected by monitoring bit error rate, bit rate and latency. • System detects islanding within 33 ms, following IEEE Std. 929-2000 and 1547-2003. • The DSSS settings, providing the highest communication efficiency, were identified. • The bypass scheme improves efficiency and applicability range of the concept. As smart grid applications, distributed generation, and microgrid technologies have become more widespread, new safety-related issues have arisen. Unintentional islanding is an example of a grid fault that may result in damage to electrical equipment and severe personal injuries. In this paper, an anti-islanding system employing power line communication (PLC) and direct-sequence spread spectrum (DSSS) modulation implemented with software-defined radios for continuous signaling is tested in a laboratory test setup. A concept of a fault detection algorithm is evaluated. A DSSS sensitivity analysis is carried out to investigate system's performance against variation of a signal-to-noise ratio, and define optimal DSSS settings. The results of the analysis are interpreted, and conclusions are drawn. A transformer bypassing scheme allowing to increase the fault detection speed and throughput is introduced and tested, and the conditions of applicability are described. As a result of the study, recommendations for the system development are presented. [ABSTRACT FROM AUTHOR]

To eliminate tethering effects on the small animals’ behavior during electrophysiology experiments, such as neural interfacing, a robust and wideband wireless data link is needed for communicating with the implanted sensing elements without blind spots. We present a software-defined radio (SDR) based scalable data acquisition system, which can be programmed to provide coverage over standard-sized or customized experimental arenas. The incoming RF signal with the highest power among SDRs is selected in real-time to prevent data loss in the presence of spatial and angular misalignments between the transmitter (Tx) and receiver (Rx) antennas. A 32-channel wireless neural recording system-on-a-chip (SoC), known as WINeRS-8, is embedded in a headstage and transmits digitalized raw neural signals, which are sampled at 25 kHz/ch, at 9 Mbps via on-off keying (OOK) of a 434 MHz RF carrier. Measurement results show that the dual-SDR Rx system reduces the packet loss down to 0.12%, on average, by eliminating the blind spots caused by the moving Tx directionality. The system operation is verified in vivo on a freely behaving rat and compared with a commercial hardwired system. [ABSTRACT FROM AUTHOR]

Abstract In this paper, bit error performance evaluation of chaotic sequences is presented. Performance of chaotic sequences is evaluated on multiple access spread spectrum system model for USRP software defined radio. LabVIEW is used to perform numerical simulations and bit error rate analysis. Chaotic sequences of different lengths are generated using one-dimensional, two-dimensional, and three-dimensional maps. It is expected that sequences generated from complex maps will have better multiple access performance. Performance of chaotic sequences is evaluated against orthogonal sequences in multiple access scenario. Using Golay figure of merit and Pearson correlation coefficient, analysis of correlation properties and a comparison is performed on orthogonal and chaotic sequences for correlation properties comparison. The results show that chaotic sequences from two-dimensional maps have lower bit error rate than orthogonal and other chaotic sequences. Comparison of correlation properties shows that sequences with a low figure of merit and low Pearson coefficient have lower bit error rate. Those results can be used to generate chaotic sequences with desired correlation properties.

In this paper, we present a novel Data-Flow architecture for MATLAB. This architecture provides thread-level pipelining of MATLAB functions as well as general concurrency support. The proposed approach yields a significant speedup of current MATLAB implementations that rely on streaming data or employ data-dependent operations. Following the development of increased CPU core counts, this proposed framework will provide additional benefit only as this trend continues. A performance analysis of the proposed framework is performed, and we are able to demonstrate high-level throughput gains of specific applications. Discussions on implementation guidelines, as well as limitations of the framework, are proposed in this paper. Through the use of this tool, we have demonstrated a 802.11a receiver employing Software-Defined Radio hardware running in real time. From the user's perspective, this tool requires interaction only from the MATLAB language, handling all threading and data transfer without user intervention.

This paper sets up a framework for designing a massive multiple-input multiple-output (MIMO) testbed by investigating hardware (HW) and system-level requirements, such as processing complexity, duplexing mode, and frame structure. Taking these into account, a generic system and processing partitioning is proposed, which allows flexible scaling and processing distribution onto a multitude of physically separated devices. Based on the given HW constraints such as maximum number of links and maximum throughput for peer-to-peer interconnections combined with processing capabilities, the framework allows to evaluate modular HW components. To verify our design approach, we present the Lund University Massive MIMO testbed, which constitutes the first reconfigurable real-time HW platform for prototyping massive MIMO. Utilizing up to 100 base station antennas and more than 50 field programmable gate array, up to 12 user equipment are served on the same time/frequency resource using an LTE-like orthogonal frequency division multiplexing time-division duplex-based transmission scheme. Proof-of-concept tests with this system show that massive MIMO can simultaneously serve a multitude of users in a static indoor and static outdoor environment utilizing the same time/frequency resource.

With the equipment of mobile terminals with multiple antennas, a bandwidth-friendly approach for increasing data rate and reliability has become the main trend in the development of future fifth generation (5G). However, this scenario presents significant challenges in the antenna and hardware design. For further system development, building real-time testbeds is a desirable track given that this endeavor can demonstrate the possibilities and limitations of the technology. In this paper, we present the design, implementation, and evaluation of a multiple input, multiple output system with eight antennas at a mobile terminal on the basis a software-defined radio (SDR) platform. The system uses long-term evolution-like system parameters. We illustrate the hierarchical hardware architecture and the implementation features, including the timing and synchronization, the processing partitioning, and the performance indicators of a particular eight-antenna module, which could meet the demands of 5G smartphone applications. Link-level simulations corresponding to the designs are conducted to validate the feasibility of the system. Accordingly, the SDR-based testbed is implemented, and a series of experiments are carried out to test the performance of our design in realistic situations. The proposed system has experimentally demonstrated its capability to transmit four-independent high-definition video streams on the same time-frequency resource.

This paper introduces a new technology called Broadband over Visible Light (BVL) which combines two technology solutions like Visible Light Communication(VLC) and Broadband over Power Line (BPL). This new technology is suitable for converting modern LED lighting systems into communication systems. However, there are some deficiencies in BVL technology such as the low bandwidth of LED optical transmitters. Pre-equalization may be solution of this problem. This paper proposes higher bandwidth using the pre-equalization circuit. Also, it shows real experimental results demonstrating an improvement of bandwidth and transmission rate.

Current wireless network simulators provide very detailed and deterministic models of the network protocol layers, whereas rather simple and stochastic models, based on the signal-to-noise ratio, are used for the simulation of the physical layer. Although this approach can be sufficient to study the behavior of different upper layer protocol variations, it prevents an easy alteration of the physical layer because a stochastic abstraction of the physical layer must be provided in advance. In particular, the simulation of distributed systems with physical layers that are designed to have several senders transmitting signals at the same time intentionally, is hardly possible with current approaches. A further problem of stochastic physical layer simulations is the fact that the radio channel's influence must also be carried out stochastically, which limits the advantage of accurate ray-optical channel models. We present a novel approach for the accurate simulation of the physical layer by utilizing existing software-defined radio implementations to create signals, to calculate interference and to decode signals. This technique enables us to simulate wireless networks holistically and, furthermore, we can fully exploit the possibilities of available ray-optical channel models.

In this work, a novel multiband spectrum sensing technique is implemented in the context of cognitive radios. This technique is based on multiresolution analysis (wavelets), machine learning, and the Higuchi fractal dimension. The theoretical contribution was developed before by the authors; however, it has never been tested in a real-time scenario. Hence, in this work, it is proposed to link several affordable software-defined radios to sense a wide band of the radioelectric spectrum using this technique. Furthermore, in this real-time implementation, the following are proposed: (i) a module for the elimination of impulsive noise, with which the appearance of sudden changes in the signal is reduced through the detail coefficients of the multiresolution analysis, and (ii) the management of different devices through an application that updates the information of each secondary user every 100 ms. The performance of these linked devices was evaluated with encouraging results: 95% probability of success for signal-to-noise ratio (SNR) values greater than 0 dB and just five samples (mean) in error of the edge detection (start and end) for a primary user transmission.

A reconfigurable gm-boosted, image-rejected downconversion mixer is presented in this paper using the SiGe 8 HP technology. The proposed mixer operates within 0.9–13.5 GHz that is suitable for software-defined radio applications. The conversion mixer comprises of resistive biased radio frequency (RF) section, double balanced Gilbert cell mixer core sections divided as per I and Q stages for image-rejection purpose, inductively peaked gm-boosting section and tunable filter section, respectively. In comparison to previous works in the scientific literature, the design shows enhanced conversion gain (CG), noise figure (NF), and image-rejection ratio (IRR). For the entire band of operation, the mixer attains a good return loss |S11| of

The idea of end-to-end learning of communication systems through neural network (NN)-based autoencoders has the shortcoming that it requires a differentiable channel model. We present in this paper a novel learning algorithm which alleviates this problem. The algorithm enables training of communication systems with an unknown channel model or with non-differentiable components. It iterates between training of the receiver using the true gradient, and training of the transmitter using an approximation of the gradient. We show that this approach works as well as model-based training for a variety of channels and tasks. Moreover, we demonstrate the algorithm’s practical viability through hardware implementation on software defined radios (SDRs) where it achieves state-of-the-art performance over a coaxial cable and wireless channel. [ABSTRACT FROM AUTHOR]

The majority of bird and bat species are incapable of carrying tags that transmit their position to satellites. Given fundamental power requirements for such communication, burdened mass guidelines and battery technology, this constraint necessitates the continued use of very high frequency (VHF) radio beacons. As such, efforts should be made to mitigate their primary deficiencies: detection range, localization time and localization accuracy.The integration of a radiotelemetry system with an unmanned aerial vehicle (UAV) could significantly improve the capacity for data collection from VHF tags. We present a UAV‐integrated radiotelemetry system that relies on open source hardware and software. Localization methods, including signal processing, bearing estimation based on principal component analysis, localization techniques and test results, are discussed.Using a low‐power beacon applicable for bats and small birds, testing showed that the improved vantage of the UAV‐radiotelemetry system (UAV‐RT) provided significantly higher received signal power compared to the low‐level flights (maximum range beyond 1.4 km). Flight testing of localization methods showed median bearing errors between 2.3° and 6.8°, with localization errors of between 5% and 14% of the distance to the tag. In a direct comparison to an experienced radiotelemetry user, the UAV‐RT system provided bearing and localization estimates with 53% less error.This paper introduces the core functionality and use methods of the UAV‐RT system, while presenting baseline localization performance metrics. An associated website hosts plans for assembly and software installation. The methods of UAV‐RT use for tag detection will be further developed in future works. For both the detection and localization problems, the mobility of a flying asset drastically reduces tracker time requirements. A 7‐min flight would be sufficient to collect five equally spaced bearing estimates over a 1‐km transect. The use of a software‐defined radio on the UAV‐RT system will allow for the simultaneous detection and localization of multiple tags. [ABSTRACT FROM AUTHOR]

Two methods for measuring the dielectric constant and loss tangent of the dielectric materials using software‐defined radio (SDR) are presented, which may be used as an alternative to the expensive vector network analysers (VNA). The first method used was the cylindrical cavity resonator designed for a resonance frequency of 2.5 GHz. The second method used was the complementary split ring resonator designed for a resonance frequency of 1.25 GHz. In both cases, measurements were carried out using VNA and SDR to compare the efficiency of both tools. The measurement accuracy was assessed by comparing the results with the declared values in the data sheets of dielectric manufacturers. The results showed a good agreement with the available data sheet values and further demonstrated that the SDR is an excellent tool for microwave measurements. [ABSTRACT FROM AUTHOR]

The paper is related to an adaptive satellite communication system for data transmission from small, low cost, low Earth orbit satellites. Tests run in a set-up consisting of a number of software-defined radio (SDR) modules operating as a satellite, a ground station, and a satellite channel simulator, have shown that by changing modulation scheme and code rate one can obtain increase of amount of data which can be downloaded from a satellite during a single pass over a ground station approximately by a factor of 2. To determine data rates obtainable in an SDR system using a common personal computer as a digital signal processing device, execution times of particular processing steps involved in the reception process were measured. [ABSTRACT FROM AUTHOR]

As the number of antenna elements increases in massive multiple-input multiple-output-based radios such as fifth generation mobile technology (5G), designing true multi-band base-station transmitter, with efficient physical size, power consumption and cost in emerging cellular frequency bands up to 10 GHz, is becoming a challenge. This demands a hard integration of radio components, particularly the radio's digital application-specific integrated circuits (ASIC) with high performance multi-band data converters. In this work, a novel radio frequency digital-to-analog converter (RF DAC) solution is presented, that is also capable of monolithic integration into today's digital ASIC due to its digital-in-nature architecture. A voltage-mode conversion method is used as output stage, and configurable mixing logic is employed in the data path to create a higher frequency lobe and utilize the output signal in the first or the second Nyquist zone. This 12-bit RF DAC is designed in a 22 nm FDSOI CMOS process, and shows excellent linearity performance for output frequencies up to 10 GHz, with no calibration and no trimming techniques. The achieved linearity performance is able to fulfill the high requirements of 5G base-station transmitters. Extensive Monte-Carlo analysis is performed to demonstrate the performance reliability over mismatch and process variation in the chosen technology. [ABSTRACT FROM AUTHOR]

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Wireless networks are extremely vulnerable to a plethora of security threats, including eavesdropping, jamming, and spoofing, to name a few. Recently, a number of next-generation cross-layer attacks have been unveiled, which leverage small changes on one network layer to stealthily and significantly compromise another target layer. Since cross-layer attacks are stealthy, dynamic, and unpredictable in nature, novel security techniques are needed. Since models of the environment and attacker's behavior may be hard to obtain in practical scenarios, machine learning techniques become the ideal choice to tackle cross-layer attacks. In this paper, we propose FORMAT, a novel framework to tackle cross-layer security attacks in wireless networks. FORMAT is based on Bayesian learning and made up by a detection and a mitigation component. On one hand, the attack detection component constructs a model of observed evidence to identify stealthy attack activities. On the other hand, the mitigation component uses optimization theory to achieve the desired trade-off between security and performance. The proposed FORMAT framework has been extensively evaluated and compared with existing work by simulations and experiments obtained with a real-world testbed made up by Ettus Universal Software Radio Peripheral (USRP) radios. Results demonstrate the effectiveness of the proposed methodology as FORMAT is able to effectively detect and mitigate the considered cross-layer attacks. [ABSTRACT FROM AUTHOR]

Congestion in the RF spectrum is rapidly increasing, which has motivated the need for efficient spectrum sharing techniques. A cognitive radar system has been developed to implement a perception action cycle, for spectrum sharing, in which the RF spectrum is sensed, other RF signals are identified, and the radar frequency band of operation is adapted to avoid interfering signals in the spectrum. The system operates in real time and is capable of coexisting with common communications signals. A system with this capability requires efficient programming that pushes the limits of the technology available. In order to properly test the performance of a radar system designed for this kind of reactive spectrum sharing, a rigorous set of synthetic interference signals is generated and several informative evaluation metrics are defined. Additionally, the system's performance is evaluated with common communications signals such as LTE and GSM. The performance of the system is found to be adequate for avoiding signals that are either varying in frequency or turning on and off at rates on the order of 10 ms. [ABSTRACT FROM AUTHOR]

It is well known that image aliasing limits the flexibility of bandpass sampling receivers. In this context, a method that utilizes a second-order bandpass sampling structure with a tunable delay to eliminate image aliasing via digital signals is proposed. The antialiasing filter in the proposed method incorporates a simplified gains model/algorithm in which image aliasing is suppressed by adjustment of the complex gain in accordance with the location/position of the RF signal in the frequency domain. The proposed algorithm is easier to implement and can realize unaliased reception regardless of the location of the RF signal. Simulation results demonstrate that bandpass signals at arbitrary positions around 0.5–6 GHz can be received through the same receiver, and image aliasing is suppressed by almost 30 dB. Thus, the proposed method improves the extensibility of the receiver. [ABSTRACT FROM AUTHOR]

This paper presents a wideband frequency-translational resistive-feedback receiver (RX), operational from 0.1 to 2.2 GHz. Different blocker suppression techniques are proposed to improve both out-of-band (OOB) compression and weakly nonlinear distortion of the RX. The blockers are first rejected at the RX input using an $N$ -path filter. Then, a blocker current cancellation (BCC) technique is used to mitigate the effect of nonlinearity in the transimpedance amplifier. By introducing an auxiliary path in the RX, the OOB linearity of the RX is further improved by means of frequency-translational noise cancellation (FTNC) and split-BCC. The RX prototype fabricated in a 130-nm CMOS process achieves 2.6–3.2-dB noise figure (NF) and tolerates a 0-dBm blocker at a 50-MHz offset with an NF of 4.9 dB. At 40-MHz offset from the local oscillator (LO), the RX exhibits higher +23-dBm out-of-band input-referred inter modulation product of order 3 (OB-IIP3) without FTNC and higher +26 dBm OB-IIP3 with FTNC. [ABSTRACT FROM AUTHOR]

Abstract This paper proposes a low noise fractional-N frequency synthesizer with quantization noise suppression techniques and a chopping differential charge pump. A level-shift-less phase frequency detector and a chopping differential charge pump are proposed to improve matching performance and suppress in-band phase noise of the frequency synthesizer. The combination of a 4/4.5 divider and a notch filter enable the design of an efficient system to suppress quantization noise and improve in-band and out-band phase noise by 3 dB and 6 dB, respectively. With all these techniques, the frequency synthesizer is implemented in a standard 65 nm CMOS process, achieving 210fs root mean square jitter and less than −70dBc reference spur with operating range from 187.5 MHz to 3 GHz. [ABSTRACT FROM AUTHOR]

In the cooperative cognitive radio networks (CRN), often secondary user (SU) relays the information of primary user (PU) as a rewarding relay to improve diversity gain of PU without being a legitimate user. So the SU needs to detect the signal, blindly estimate the parameters introduced in channel and reconstruct the signal before relaying it to the primary receiver. In this paper, a joint scheme for signal detection and non-data-aided (blind) parameter estimation of orthogonal frequency division multiplexing (OFDM) based CRN has been discussed. Based upon binary hypothesis testing problem, the SU formulates a minimum cost signal detection scheme for the presence of OFDM based PU signal in CRN. The probability of detection, probability of false alarm and receiver operating characteristics have been presented to illustrate the performance of signal detection scheme in the CRN. Further, the effective throughput analysis of the secondary system has been demonstrated in the context when the primary system is detected as idle. Blind synchronous parameters of OFDM signal such as carrier frequency offset and symbol timing offset has been presented over the wireless fading channel in the CRN. Existing theoretical studies on blind parameter estimation algorithms for signals have been carried out but most of them have not been implemented in order to validate their feasibility. Here, a software-defined radio testbed has been implemented using national instruments hardware in a multipath indoor environment and experimental results have been provided using real measurement system. The preliminary measurement and simulation results demonstrate that the proposed blind estimator is capable of estimating the concerned parameters and constellation symbols over an indoor propagation environment. [ABSTRACT FROM AUTHOR]

While cellular networks connect over 3.7 billion people worldwide, their availability and quality is not uniform across regions. Under-provisioned and overloaded networks, as are common in rural or post-disaster areas, lead to poor network performance and a poor-quality user experience. To address this problem, we propose HybridCell: a system that leverages locally-owned small-scale cellular networks to augment the operation of overloaded commercial networks. HybridCell is the first system to allow a user with their existing SIM card and mobile phone to seamlessly switch between commercial and local networks in order to maintain continuous connectivity. HybridCell accomplishes this by identifying poorly-performing networks and taking action to provide seamless cellular connectivity to end users. Using traces from commercial cellular networks collected during our visit to the Za'atari refugee camp in Jordan, we demonstrate HybridCell's capability to detect and act upon commercial network overload, offering an alternate communication channel during times of congestion. We show that even in scenarios where provider networks deny calls due to overload, HybridCell is able to accommodate users and facilitate local calling. [ABSTRACT FROM AUTHOR]

Based on the bandpass sampling theorem,the system obtains the spectrum of the UAV using software defined radio( SDR) platform under a low sampling rate. We analyze the signals of the UAV and the remote controller by using the 5. 8 GHz wireless technique. They use frequency hopping and share the same frequency band. By checking the hopping series,we use the finite state machine to get more stable detection results. We also get the approximate direction of the UAV by the phase difference of two signal channels. [ABSTRACT FROM AUTHOR]

Direction-of-arrival (DOA) systems rely on proper phase measurements acquired from receiving antennas for optimal performance. Unfortunately, imperfections in any antenna and receiver system may present false phase measurements, the major cause of DOA estimation error. This paper discusses experimental results from an actual implementation of synchronizing a DOA circular array receiver system to mitigate these imperfections. A reference signal located at the center of the DOA array was coupled to array elements such that both the coupled reference signals and signals from a target were captured simultaneously in the receiver. This coupled reference signal was used to compensate for any phase error offsets produced by receiver system imperfections on cable length, phase of local oscillators, and phase delays in active devices. Furthermore, this approach did not necessitate an off-line calibration process of each receiver channel requiring accurate measurements. We implemented a 16-element circular array DOA estimation system using the Universal Software Radio Peripheral platform operating in the $S$ - and $C$ -bands. Results show that this implementation was able to combat receiver phase offset errors and estimated the DOA angles with an rms error of 0.92°. [ABSTRACT FROM AUTHOR]

In order to secure wireless communications, we consider the usage of physical-layer security (PLS) mechanisms (i.e., coding for secrecy mechanisms) combined with self-interference generation. We present a prototype implementation of a scrambled coding for secrecy mechanisms with interference generation by the legitimate receiver and the cancellation of the effect of self-interference (SI). Regarding the SI cancellation, four state-of-the-art algorithms were considered: Least mean square (LMS), normalized least mean square (NLMS), recursive least squares (RLS) and QR decomposition recursive least squares (QRDRLS). The prototype implementation is performed in real-world software-defined radio (SDR) devices using GNU-Radio, showing that the LMS outperforms all other algorithms considered (NLMS, RLS and QRDRLS), being the best choice to use in this situation (SI cancellation). It was also shown that it is possible to secure communication using only noise generation by the legitimate receiver, though a variation of the packet loss rate (PLR) and the bit error rate (BER) gaps is observed when moving from the fairest to an advantageous or a disadvantageous scenario. Finally, when noise generation was combined with the adapted scrambled coding for secrecy with a hidden key scheme, a noteworthy security improvement was observed resulting in an increased BER for Eve with minor interference to Bob.