Wireless Open Access Research Platform Research Articles

On companding techniques for PAPR reduction in DCT SC-FDMA system in the presence of CFOs

In the single carrier frequency division multiple access (SC-FDMA) system, the use of discrete cosine transform (DCT) instead of discrete Fourier transform (DFT) has shown improved bit error rate (BER) performance. Nevertheless, peak-to-average power ratio (PAPR) in the DCT-based SC-FDMA system is higher than that in the DFT-based system. This paper investigates the performance of various companding schemes to reduce PAPR in DCT-based SC-FDMA systems by considering carrier frequency offsets (CFOs). Simulation results, considering parameters like BER, PAPR, and power spectral density (PSD), are provided to find the best companding technique. Furthermore, the results have been validated in a real-time indoor channel using a wireless open-access research platform (WARP) hardware.

Performance of OFDM Communication System with Network Coding using Wireless Open-Access Research Platform

Performance of OFDM Communication System with Network Coding using Wireless Open-Access Research Platform

Over-the-Air Adversarial Attacks on Deep Learning Wi-Fi Fingerprinting

Empowered by deep neural networks (DNNs), Wi-Fi fingerprinting has recently achieved astonishing localization performance to facilitate many security-critical applications in wireless networks, but it is inevitably exposed to adversarial attacks, where subtle perturbations can mislead DNNs to wrong predictions. Such vulnerability provides new security breaches to malicious devices for hampering wireless network security, such as malfunctioning geofencing or asset management. The prior adversarial attack on localization DNNs uses additive perturbations on channel state information (CSI) measurements, which is impractical in Wi-Fi transmissions. To transcend this limitation, this paper presents FooLoc, which fools Wi-Fi CSI fingerprinting DNNs over the realistic wireless channel between the attacker and the victim access point (AP). We observe that though uplink CSIs are unknown to the attacker, the accessible downlink CSIs could be their reasonable substitutes at the same spot. We thoroughly investigate the multiplicative and repetitive properties of over-the-air perturbations and devise an efficient optimization problem to generate imperceptible yet robust adversarial perturbations. We implement FooLoc using commercial Wi-Fi APs and Wireless Open-Access Research Platform (WARP) v3 boards in offline and online experiments, respectively. The experimental results show that FooLoc achieves overall attack success rates of about 70% in targeted attacks and of above 90% in untargeted attacks with small perturbation-to-signal ratios of about -18 dB.

Double-Stream Differential Chaos Shift Keying Communications Exploiting Chaotic Shape Forming Filter and Sequence Mapping

A new Differential Chaos Shift Keying modulation scheme exploiting Chaotic Shape-forming Filter and Sequence Mapping (CSF-SM-DCSK) is being proposed. The new CSF-SM-DCSK system employs a novel sequence mapping rule and includes a data correction module to achieve a good trade-off between the low Bit Error Rate (BER) performance and high transmission rate. It transmits two data streams simultaneously and preserves the simplicity and robustness of DCSK method. Channel one, transmitting a Low Priority Stream (LPS), generates the chaotic carrier by a Chaotic Shape-forming Filter (CSF) at the transmitter and applies a coherent Matched Filter (MF) at the receiver to recover the information. Channel two, transmitting a High Priority Stream (HPS), relies on conventional DCSK modulation, while the reference and information-bearing parts are transmitted simultaneously with orthogonal sine and cosine carriers. This double-stream solution eliminates the need for analog RF delay lines and doubles the data transmission rate. Before feeding the LPS data stream into the modulator, each LPS bit is encoded into a symbol sequence using sequence mapping. This approach, together with the coherent MF reception, equips the LPS channel with an extremely high robustness against channel noise and multipath propagation. To handle every possible redundancy in the received signal and to minimize the possibility of making wrong decisions, a data correction block is also introduced. Initially, a rough estimation of the received HPS DCSK bit is done at the receiver, then this estimation is used to remove the DCSK modulation from the received information-bearing signal. The three inputs of data correction blocks are: (i) the reference and (ii) the information-bearing parts of the received signal in their original form, and (iii) the received information-bearing signal where the DCSK modulation is removed. The data correction block improves the BER performance while the increased channel capacity, enabled by the double-stream approach, improves the spectral efficiency. Analytical expressions are derived to predict the BER performances in additive white Gaussian noise channel for both the LPS and HPS channels. Computer simulations are used to show that the system performance of the CSF-SM-DCSK modulation scheme proposed in this work is superior to that of the already published solutions. In addition to the computer simulations, the new chaos-based wireless communications system has been implemented on a wireless open-access research platform to experimentally demonstrate the feasibility and the superiority of CSF-SM-DCSK.

Echo state network based symbol detection in chaotic baseband wireless communication

The Chaotic Baseband Wireless Communication System (CBWCS) is expected to eliminate the Inter-Symbol Interference (ISI) caused by multipath propagation by using the optimal decoding threshold that is the sum of the ISI caused by past decoded bits and the ISI caused by future transmitting bits. However, the current technique is only capable of removing partial effects of the ISI, because only past decoded bits are available for the sub-optimal decoding threshold calculation. The unavailability of the future information needed for the optimal decoding threshold is an obstacle to further improve the Bit Error Rate (BER) performance. In contrast to the previous method using Echo State Network (ESN) to predict one future bit, the proposed method in this paper predicts the optimal decoding threshold directly using ESN. The proposed ESN-based threshold prediction method simplifies the symbol decoding operation by avoiding the iterative prediction of the output waveform points using ESN and accumulated error caused by the iterative operation. With this approach, the calculation complexity is reduced compared to the previous ESN-based approach. The proposed method achieves better BER performance compared to the previous method. The reason for this superior result is twofold. First, the proposed ESN is capable of using more future symbols information conveyed by the ESN input to obtain more accurate threshold rather than the previous method in which only one future symbol was available. Second, the proposed method here does not need to estimate the channel information using Least Squared (LS) method, which avoids the extra error caused by inaccurate channel information estimation. Simulation results and experiment based on a wireless open-access research platform under a practical wireless channel show the effectiveness and superiority of the proposed method.

A Joint Time-Domain Channel Estimation with Hybrid PAPR Reduction Scheme in UFMC Systems

In this paper, pilot-based time-domain channel estimation (CE) along with peak-to-average power ratio (PAPR) reduction is proposed for universal filtered multicarrier (UFMC) system. The pilots that are inserted in time domain not only estimate the channel behavior but also can be used in the reduction of PAPR. For PAPR reduction, a linear companding scheme, which can treat amplitudes of the UFMC signal separately with a different scale, is proposed. The proposed companding scheme offers more design flexibility and better performance gains by using two inflexion points. However, the proposed companding scheme requires side information (SI) to perform de-companding at the receiver. The transmission of SI decreases the data efficiency, so a pilot-assisted UFMC system that can perform both data recovery and PAPR reduction without the requirement of SI transmission is proposed. In pilot-assisted UFMC system, the inserted time-domain pilots can enable SI cancellation inherently. Furthermore, a hybrid transform, which improves PAPR performance by employing clipping scheme to the linear companded signal, is proposed. Simulation results confirm that the proposed joint CE with linear companding scheme achieves an improved net gain of 6.5[Formula: see text]dB. Additionally, the proposed hybrid scheme with clipping threshold of 1.4 provides an improved PAPR reduction of 8.8[Formula: see text]dB and enhanced net gain of 7.3[Formula: see text]dB. Moreover, the proposed joint time-domain CE with hybrid PAPR reduction scheme of UFMC system is validated over real time by employing wireless open-access research platform (WARP) board.

Cross Correction and Chaotic Shape-Forming Filter Based Quadrature Multi-Carrier Differential Chaos Shift Keying Communication

In this paper, an improved Quadrature Multi-carrier Differential Chaos Shift Keying (QMC-DCSK) based on Chaotic Shape-forming Filter (CSF) and Cross Correction (CC) is proposed. The chaotic signal generated by CSF is used as reference spreading sequence in QMC-DCSK. Quadrature multi-carriers are used to carry the reference and multiple information bearing signals simultaneously in order to improve the Bit Transmission Rate (BTR). By this way, the proposed system is able to transmit <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$2M-1$</tex-math></inline-formula> bits Traditional Data Stream (TDS) during one traditional DCSK bit duration, where <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$M$</tex-math></inline-formula> is the number of carrier frequencies. Meanwhile, the reference signal transmits Additional Data Stream (ADS) encoded by CSF together with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$2M-1$</tex-math></inline-formula> identical or inverse data stream carried by the rest <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$2M-1$</tex-math></inline-formula> channels (information bearing signals). By this system configuration, the channel redundance can be used to improved bit error rate (BER) performance of ADS, after decoding TDS. In turn, the TDS reliability can also be improved by checking most ADS polarity of the corresponding carrier. This process is referred to as CC. The contribution of this work lies in the CC operation, by which the reliability of both TDS and ADS is improved significantly. It is the CSF and multi-carrier that make CC possible. The analytical BER is derived for the proposed method. The merits of the proposed system include, first, it improves the BTR as compared to that of QMC-DCSK, because ADS conveys more information bits; second, the ADS reliability is improved dramatically because the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\text{2}\,M$</tex-math></inline-formula> duplication can be used to improve the signal to noise ratio; third, the TDS reliability is improved as well because the information bits conveyed by each carrier frequency is enhanced and corrected by the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\text{2}\,M$</tex-math></inline-formula> repetitions. By this way, not only TDS and ADS are transmitted (i.e., the higher BTR is achieved), but also both reliability are improved (i.e. the lower BER is achieved). In order to testify the feasibility and superiority of the proposed method, simulation and wireless open-access research platform (WARP) experiment are conducted. The simulation and experiment results show that the proposed method is superior to other comparison methods.

Enabling Detection of Plastic Debris on Water Surface Using Wireless Signals

Current systems for monitoring of water surfaces are largely camera-based and remote-sensing based. While remote-sensing based systems have low resolution and cannot provide data for smaller scales of water surface, continuous processing of video footage from vision-based systems can be expensive. In this letter, we propose and evaluate a system for detection of floating debris on water surface by leveraging wireless signals. We detect low-reflecting floating debris such as plastic by sensing their effect on water waves. Such a system can assist the present systems for monitoring of health of water bodies. We carry out our evaluations using a WARP (Wireless Open-Access Research Platform) v3 node and present our initial results for our evaluations in indoor environment and include outdoor data collected over an outdoor swimming pool. The system is able to identify the presence of floating debris and is also able to distinguish between still stagnant water versus water with disturbance and can, hence, also be used to monitor water flow and turbulence.

Direct symbol decoding using GA-SVM in chaotic baseband wireless communication system

To retrieve the information from the serious distorted received signal is the key challenge of communication signal processing. The chaotic baseband communication promises theoretically to eliminate the inter-symbol interference (ISI), however, it needs complicated calculation, if it is not impossible. In this paper, a genetic algorithm support vector machine (GA-SVM) based symbol detection method is proposed for chaotic baseband wireless communication system (CBWCS), by this way, treating the problem from a different viewpoint, the symbol decoding process is converted to be a binary classification through GA-SVM model. A trained GA-SVM model is used to decode the symbols directly at the receiver, so as to improve the bit error rate (BER) performance of the CBWCS and simplify the symbol detection process by removing the channel identification and the threshold calculation process as compared to that using the calculated threshold to decode symbol in the traditional methods. The simulation results show that the proposed method has better BER performance in both the static and time-varying wireless channels. The experimental results, based on the wireless open-access research platform, indicate that the BER of the proposed GA-SVM based symbol detection approach is superior to the other counterparts under a practical wireless multipath channel.

Walsh‐Hadamard‐transform‐based SC‐FDMA system using WARP hardware

Single-carrier frequency division multiple access (SC-FDMA) is currently being used in long-term evolution uplink communications owing to its low peak-to-average power ratio (PAPR). This study proposes a new transceiver design for an SC-FDMA system based on Walsh-Hadamard transform (WHT). The proposed WHT-based SC-FDMA system has low-PAPR and better bit-error rate (BER) performance compared with the conventional SC-FDMA system. The WHT-based SC-FDMA transmitter has the same complexity as that of discrete Fourier transform (DFT)-based transmitter, while the receiver's complexity is higher than that of the DFT-based receiver. The exponential companding technique is used to reduce its PAPR without degrading its BER. Moreover, the performances of different ordered WHT systems have been studied in additive white Gaussian noise and multipath fading environments. The proposed system has been verified experimentally by considering a real-time channel with the help of wireless open-access research platform hardware. The supremacy of the proposed transceiver is demonstrated based on simulated and experimental results.

Double-Sub-Stream M-ary Differential Chaos Shift Keying Wireless Communication System Using Chaotic Shape-Forming Filter

An M-ary Differential Chaos Shift Keying modulation using Chaotic Shape-forming Filter (CSF-M-DCSK) is proposed here to transmit two sub-streams with different system performances. The chaotic shape-forming filter is used to generate the chaotic carrier which is modulated according to the DCSK concept. The modulated chaotic signal is demodulated by a coherent matched filter receiver and the maximum likelihood decision rule is used to get the best noise performance. Compared to DCSK and its enhanced versions, the new modulation scheme offers not only better noise and multipath performances but also a higher data rate. The hardware implementation of the proposed method is as simple as that of a conventional communication system. Analytical expressions have been derived for the CSF-M-DCSK Bit Error Rate (BER) and its performance has been evaluated in AWGN and multipath channels by simulations. The new CSF-M-DCSK system has been implemented and successfully tested on a Wireless open-Access Research Platform (WARP). Results of simulations and measurements performed in real application scenarios have proven the feasibility and superiority of CSF-M-DCSK over its competitors.

An optimal nonlinear companding transform with clipping scheme for universal filtered multicarrier systems

SummaryIn this article, an exponential companding (EC) scheme, which can reduce PAPR without raising the average output power level, is proposed for universal filtered multi carrier (UFMC) signals. However, EC scheme degrades the BER performance. Therefore, an optimal nonlinear companding transform named as “modified exponential companding” (MEC), which can use two companding levels based on a threshold value, is proposed. The proposed MEC scheme shows enhanced PAPR and BER performances than EC scheme. Moreover, the MEC provides more design flexibility and freedom with an unchanged average output power level. Furthermore, a hybrid scheme is also proposed to improve PAPR performance, where clipping operation is employed on MEC signal based on an appropriate clipping threshold. Simulation results illustrate that proposed MEC scheme offers improved system performance with a net gain of 7.22 dB than conventional EC and μ‐law techniques. Besides, the proposed hybrid scheme with clipping ratio 1.3 proffers enhanced PAPR reduction of 8.85 dB and improved net gain of 7.95 dB. Also, the proposed EC, MEC, and hybrid schemes can provide lesser spectrum side‐lobe levels than μ‐law. Finally, the UFMC system with the proposed hybrid scheme is verified by employing wireless open‐access research platform (WARP) as hardware over real‐time channel.

Golden Coded GFDM for 5G Communication

The 5th Generation (5G) of wireless communication will be heterogeneous to support various traffic types and applications. Generalized Frequency Division Multiplexing (GFDM) is a 5G non-orthogonal waveform contender that offers scalable and spectrally compliant air interface which addresses the needs of 5G requirements. To aid the demand of high-capacity and reliable transmission, multiple antenna techniques are relied upon. In this work, the 5G modulation scheme GFDM is combined with a full rate Space–Time Block Code (STBC) with nonvanishing determinant called Golden Codes to exploit the diversity to the fullest. The proposed work is implemented in a real-time SDR test-bed called Wireless Open Access Research Platform (WARP). The proposed work is compared with 4G OFDM modulation in both Golden Coded and Uncoded case. The performance is assessed in terms of BER and Capacity/Bandwidth resolution. From the investigations, it is seen that the BER performance of Golden Coded GFDM outperforms the Uncoded GFDM by 3 dB SNR gain and attains a near-equal performance as OFDM. Also, it is evident from the analysis that, there is a 3.5 bps/Hz gain in capacity when compared to OFDM.

Performance Improvement of Chaotic Baseband Wireless Communication Using Echo State Network

The inter-symbol interference (ISI) caused by multipath propagation in wireless channel is one of the main reasons for high bit error rate (BER) in wireless communication system. Chaos was proved to be an ideal communication baseband signal because of its special properties, including the corresponding simple matched filter and multipath resistance ability. Although the ISI caused by the multipath is promised to be completely eliminated by using the optimal symbol decoding threshold, the future symbols are needed to be known for calculating the optimal threshold, which is hard to be practically implemented. To deal with such problem, an echo state network (ESN), because of its short-term memory ability, is proposed to predict the future chaotic baseband signal based on the signal received after the matched filter. Thus, the first future symbol is estimated, which is used to improve the accuracy of the decoding threshold in the chaotic baseband wireless communication system (CBWCS) in order to further relieve the effect of ISI. Compared to the sub-optimal decoding threshold considering only past symbols, the improved threshold proposed here considers not only the ISI from past symbols, but also the ISI from one future symbol. The simulation in both the static and time-varying wireless channels are performed, the results show that the BER performance of CBWCS is improved more significantly in multipath channels as compared to single path channel. The experiments based on wireless open-access research platform verify the ISI resistance performance under the practical scenarios. Both simulation and experimental results show the effectiveness and the superiority of the proposed method.

Towards cloud energy metering system with 32 bit FPGA device architecture

Cloud based Advanced Metering Infrastructure (CAMI) is the next digital future for energy management (EM). Various efforts on EM capabilities are mainly skewed towards embedded device architectures that support non-concurrent execution. This paper presents cloud energy metering system (CEMS) using high speed 32 bit field programmable gate array (FPGA) device. The architectural framework for energy tracking and profile measurement in CEMS is presented. This aims at accurate metering with demand side management (DSM). An application context that supports an EM architecture is highlighted. The contextual CEMS features energy monitoring in distributed energy utilities such as solar generators, wind and energy storage sources. Process integration with Cloud based Internet for real-time energy reading is achieved through the FPGA synthesis to provide end-to-end energy analytics. CEM prototype (Xilinx FPGA) running on a wireless open-access research platform supports management of large historical data-sets from the current data up to the last granular interval, hourly, daily, monthly and yearly dataset captures. The system provides the low latency datasets in both tabular and graphical forms for end-user visualization of energy consumption patterns. In the experimental setup, three case scenarios demonstrate how the metering system executes fast edge computing profiling, thereby providing data-visualization services to end-users. The results show the Avg. Latency time for CAMI household 1, 2 and 3 respectively. In case 1, the average latencies for actual and measured (proposed CAMI) are 75% and 25% respectively. In case 2 and case 3, this gave 66.67% and 33.33% respectively. Clearly, the proposed CAMI offers lower latency for all scenarios of energy consumption metering usage.Keywords: Advanced Metering, Energy management, Cyber-physical systems, Cloud Computing, IoT, Fog. 1.0 INTRODUCTION

Amplitude-Modulating Analog/RF Hardware Trojans in Wireless Networks: Risks and Remedies

We investigate the risk posed by amplitude-modulating analog/RF hardware Trojans in wireless networks and propose a defense mechanism to mitigate the threat. First, we introduce the operating principles of amplitude-modulating analog/RF hardware Trojan circuits and we theoretically analyze their performance characteristics. Subject to channel conditions and hardware Trojan design restrictions, this analysis seeks to determine the impact of these malicious circuits on the legitimate communication and to understand the capabilities of the covert channel that they establish in practical wireless networks, by characterizing its error probability. Next, we present the implementation of two hardware Trojan examples on a Wireless Open-Access Research Platform (WARP)-based experimental setup. These examples reside in the analog and the RF circuitry of an 802.11a/g transmitter, respectively, where they manipulate the transmitted signal characteristics to leak their payload bits. Using these examples, we demonstrate (i) attack robustness, i.e., ability of the rogue receiver to successfully retrieve the leaked data, and (ii) attack inconspicuousness, i.e., ability of the hardware Trojan circuits to evade detection by existing defense methods. Lastly, we propose a defense mechanism that is capable of detecting analog/RF hardware Trojans in WiFi transceivers. The proposed defense, termed Adaptive Channel Estimation (ACE), leverages channel estimation capabilities of Orthogonal Frequency Division Multiplexing (OFDM) systems to robustly expose the Trojan activity in the presence of channel fading and device noise. Effectiveness of the ACE defense has been verified through experiments conducted in actual channel conditions, namely over-the-air and in the presence of interference.

Experimental Validation of Improved Exponential Companding Technique for SC-FDMA Systems Using WARP Hardware

As single-carrier frequency division multiple access (SC-FDMA) is used in long-term evolution (LTE) uplink communications, high peak-to-average power ratio (PAPR) increases power consumption in mobile devices. It is severe when localized subcarrier mapping is used with higher-order modulations. Companding is an attractive technique that offers a tradeoff between PAPR and bit error rate (BER) performances. This paper proposes an exponential companding technique that uses two companding levels based on a threshold, to reduce PAPR in SC-FDMA systems. It does not increase the average power level of transmitted signal and maintains the BER level without significant degradation from the original system. The proposed scheme has three parameters that can be adjusted for a tradeoff between PAPR, BER, and power spectral density (PSD) performances. Hence it offers more flexibility than the conventional exponential companding scheme. We also present scatter plots to find the optimum threshold value and companding levels. Finally, we verify the proposed technique considering a real-time indoor channel by using a wireless open-access research platform (WARP).

Demonstrating and Mitigating the Risk of an FEC-Based Hardware Trojan in Wireless Networks

We discuss the threat that malicious circuitry (a.k.a. hardware Trojan) poses in wireless communications and propose a remedy for mitigating the risk. First, we present and theoretically analyze a stealthy hardware Trojan embedded in the forward error correction (FEC) block of an 802.11a/g transceiver. FEC seeks to shield the transmitted signal against noise and other imperfections. This capability, however, may be exploited by a hardware Trojan to establish a covert communication channel with a knowledgeable rogue receiver. At the same time, the unsuspecting legitimate receiver continues to correctly recover the original message, despite experiencing a slight reduction in signal-to-noise ratio (SNR) and, therefore, remains oblivious to the attack. Next, we implement this hardware Trojan on an experimental setup based on the Wireless Open Access Research Platform (WARP) and we demonstrate (i) attack robustness, i.e., the ability of the rogue receiver to correctly receive the leaked information and (ii) attack inconspicuousness, i.e., imperceptible impact on the legitimate transmission. Lastly, we theoretically analyze and experimentally evaluate a Trojan-agnostic detection mechanism, namely, channel noise profiling, which monitors the noise distribution to identify inconsistencies caused by hardware Trojans, regardless of their implementation details. The effectiveness of channel noise profiling is experimentally assessed using the proposed hardware Trojan under various channel conditions and a different covert Wi-Fi attack previously proposed in the literature.

Interactive Trial and Error Learning Method for Distributed Channel Bonding: Model, Prototype Implementation, and Evaluation

Channel bonding (CB) has been proposed as a technique to accommodate growing data rate demands in shared spectrum (SS) bands, such as in the 5-GHz unlicensed band. Using CB, a wireless user can combine multiple non-overlapping channels into one wide channel. In practice, efficient CB utilization in SS bands can be challenging as diverse owners of networks can deploy and operate heterogeneous technologies in an uncoordinated manner. This paper leverages a game theoretic learning rule for efficient distributed channel/bonding selection. Using the proposed method, each user occasionally measures channels to try out new channel/bonding selections, rejecting those selections that are erroneous in the sense that they do not lead to higher utility. Using both analytical and simulation results, we perform a Nash equilibrium assessment of the proposed method. Using various performance metrics, we analyze and compare the performance of the proposed method with a centralized solution and also with conventional distributed CB selection solutions. To realize a complete over-the-air (OTA) channel/bonding selection solution, we also implement a prototype of the proposed method on the wireless open-access research platform. Performance of the implemented prototype is evaluated by experiments which use real OTA wireless communications.

Experimental Phase Separation Differential Chaos Shift Keying Wireless Communication Based on Matched Filter

New findings have been identified recently for chaos application in communication systems, including the simplest matched filter to maximize the signal-to-noise ratio (SNR) and the ability to resist multi-path propagation. However, chaos has a broad band frequency spectrum, which impedes its application in the conventional wireless communication systems due to the antenna and transducer bandwidth. To deal with such problem, the chaos generated by a second order hybrid system (SOHS) with a fixed basis function is used for Differential Chaos Shift Keying (DCSK) communication. A sinusoidal and its orthogonal signal are used to separate the reference signal and the information bearing signal, which are transmitted in the wireless channel. In such a way, the obstacle to broadband signal transmission in a wireless channel is overcome. A matched filter, using the convolution of the received signal and the time reverse of the basis function, maximizes the SNR at the receiver. Moreover, the proposed SOHS-DCSK provides an additional bitstream due to the chaotic signal generated by the SOHS, being capable to encode information as well. The two information sub-streams can be transmitted simultaneously in the proposed method, which possesses different bit transmission rates and reliability. In this way, the High Priority (HP) information bits are transmitted at a low transmission rate, while the Low Priority (LP) information bits are transmitted at a higher transmission rate. Hence, the proposed SOHS-DCSK method not only provides a higher data transmission rate as compared to the conventional DCSK but also makes the transmitted signal to be compatible with the conventional transducer and antenna. Due to the matched filter used, the proposed method achieves a lower bit error rate of the HP information as compared to the other existing enhanced DCSK variants for both additive white Gaussian noise channel and wireless communication channel. The numerical simulations and experiments based on the wireless open-access research platform show the validity and superiority of the proposed method.