Wireless Communication Scheme Research Articles

Driver Behavior Modeling: Developments and Future Directions

The advances in wireless communication schemes, mobile cloud and fog computing, and context-aware services boost a growing interest in the design, development, and deployment of driver behavior models for emerging applications. Despite the progressive advancements in various aspects of driver behavior modeling (DBM), only limited work can be found that reviews the growing body of literature, which only targets a subset of DBM processes. Thus a more general review of the diverse aspects of DBM, with an emphasis on the most recent developments, is needed. In this paper, we provide an overview of advances of in-vehicle and smartphone sensing capabilities and communication and recent applications and services of DBM and emphasize research challenges and key future directions.

A novel anti-intercepting wireless communication scheme

In this paper, a novel wireless communication scheme is proposed, which has high anti-intercepting ability without the frequency efficiency loss. In this scheme, we use the baseband mixed signal to construct the transmission signal, which is consisted of two independent and useful baseband signals. According to our analysis, we find that the baseband mixed signal transmission scheme can achieve higher anti-intercepting ability than the existing mixed signal schemes, and it can achieve high frequency efficiency since the mixed signals carry useful information simultaneously. We also provide a low-complexity reception algorithm based Gibbs sampling for the proposed scheme. According to simulation results, we demonstrate that the proposed scheme is effective, and validate its anti-intercepting ability.

Noisy Compressive Sampling Based on Block-Sparse Tensors: Performance Limits and Beamforming Techniques

Compressive sampling (CS) is an emerging research area for the acquisition of sparse signals at a rate lower than the Shannon sampling rate. Recently, CS has been extended to the challenging problem of multidimensional data acquisition. In this context, block-sparse core tensors have been introduced as the natural multidimensional extension of block-sparse vectors. The $(M_1,\ldots,M_Q)$ block sparsity for a tensor assumes that $Q$ support sets, characterized by $M_q$ indices corresponding to the nonzero entries, fully describe the sparsity pattern of the considered tensor. In the context of CS with Gaussian measurement matrices, the Cramer–Rao bound (CRB) on the estimation accuracy of a Bernoulli-distributed block-sparse core tensor is derived. This prior assumes that each entry of the core tensor has a given probability to be nonzero, leading to random supports of truncated Binomial-distributed cardinalities. Based on the limit form of the Poisson distribution, an approximated CRB expression is given for large dictionaries and a highly block-sparse core tensor. Using the property that the mode unfolding matrices of a block-sparse tensor follow the multiple-measurement vectors (MMV) model with a joint sparsity pattern, a fast and accurate estimation scheme, called Beamformed mOde based Sparse Estimator (BOSE), is proposed in the second part of this paper. The main contribution of the BOSE is to “map” the MMV model onto the single MV model, thanks to beamforming techniques. Finally, the proposed performance bounds and the BOSE are applied in the context of CS to $\text{1}\text{)}$ nonbandlimited multidimensional signals with separable sampling kernels and $\text{2)}$ for multipath channels in a multiple-input multiple-output wireless communication scheme.

Design and ARM‐embedded implementation of a chaotic map‐based multicast scheme for multiuser speech wireless communication

SummaryThis paper proposes a chaotic map‐based multicast scheme for multiuser speech wireless communication and implements it in an ARM platform. The scheme compresses the digital audio signal decoded by a sound card and then encrypts it with a three‐level chaotic encryption scheme. First, the position of every bit of the compressed data is permuted randomly with a pseudo‐random number sequence (PRNS) generated by a 6‐D chaotic map. Then, the obtained data are further permuted in the level of byte with a PRNS generated by a 7‐D chaotic map. Finally, it is operated with a multiround chaotic stream cipher. The whole system owns the following merits: the redundancy in the original audio file is reduced effectively and the corresponding unicity distance is increased; the balancing point between a high security level of the system and real‐time conduction speed is achieved well. In the ARM implementation, the framework of communication of multicast–multiuser in a subnet and the Internet Group Manage Protocol is adopted to obtain the function of communication between one client and other ones. Comprehensive test results were provided to show the feasibility and security performance of the whole system. Copyright © 2016 John Wiley & Sons, Ltd.

A 2.2 <inline-formula> <tex-math notation="LaTeX">$\mu\text{W}$</tex-math> </inline-formula>, <inline-formula> <tex-math notation="LaTeX">$-$</tex-math> </inline-formula>12 dBm RF-Powered Wireless Current Sensing Readout Interface IC With Injection-Locking Clock Generation

This paper presents a wireless-powering current-sensing readout system on a CMOS platform for portable electrochemical measurement. The wireless sensing system includes energy-efficient power management circuitry, a sensor readout interface, and a backscattering wireless communication scheme. For power-and-area-constrained bio-sensing applications, the proposed readout circuitry incorporates an ultra-low-power potentiostatic system that generates a current according to the electrochemical reaction, as well as an oscillator-based time-to-digital converter instead of a voltage-domain analog-to-digital converter. To avoid a bulky battery and power-hungry clock reference, the chip is wirelessly powered and injection-locked by the modulated radio waves, which includes a 918 MHz carrier signal mixed with a 3.2 MHz modulated signal. The chip, implemented using a 0.18- $\mu\text{m}$ CMOS process, occupies a silicon area of 1 $\text{mm}^{2}$ . The proposed design achieves a sensitivity of 289 Hz/nA and an ${R}^{2}$ linearity of 0.997 over a current range of 200 nA while consuming 2.2 $\mu\text{W}$ at a supply voltage of 0.8 V. The chip, integrated with a PCB antenna, has minimum sensitivities of $-$ 12 dBm and $-$ 25 dBm for RF-powering and injection-locking mechanisms, respectively.

On opportunistic spectrum access in radar bands: Lessons learned from measurement of weather radar signals

The need for extra spectrum and the fact that a large amount of spectrum below 6 GHz is allocated to radar systems has motivated regulatory bodies and researchers to investigate the feasibility of dynamic spectrum access in radar bands. To design efficient wireless communication schemes that coexist with radar systems, it is essential that the wireless community thoroughly understand the operations of these systems in different bands. This article studies incumbent operations and usage patterns in the 5 GHz band, where weather radar systems dominate, dynamic frequency selection is employed as a sharing mechanism, and recent works have explored the possibility to temporally share the spectrum with such radar systems. We present a measurement-based study of spectrum usage by a weather radar in Finland. Our measurement results show that the weather radar's scan patterns are quasi-periodic, and that use of sensing may not reliably detect radar signals due to its quasi-periodic scanning patterns and different vertical scanning angles. Finally, we present a framework for a database-assisted temporal sharing coexistence mechanism that takes into account the real occupancy behavior of the radar.

Enhanced modulation rates via field modulation in spin torque nano-oscillators

Spin Transfer Nano-Oscillators (STNOs) are promising candidates for telecommunications applications due to their frequency tuning capabilities via either a dc current or an applied field. This frequency tuning is of interest for Frequency Shift Keying concepts to be used in wireless communication schemes or in read head applications. For these technological applications, one important parameter is the characterization of the maximum achievable rate at which an STNO can respond to a modulating signal, such as current or field. Previous studies of in-plane magnetized STNOs on frequency modulation via an rf current revealed that the maximum achievable rate is limited by the amplitude relaxation rate Γp, which gives the time scale over which amplitude fluctuations are damped out. This might be a limitation for applications. Here, we demonstrate via numerical simulation that application of an additional rf field is an alternative way for modulation of the in-plane magnetized STNO configuration, which has the advantage that frequency modulation is not limited by the amplitude relaxation rate, so that higher modulation rates above GHz are achievable. This occurs when the modulating rf field is oriented along the easy axis (longitudinal rf field). Tilting the direction of the modulating rf field in-plane and perpendicularly with respect to the easy axis (transverse rf field), the modulation is again limited by the amplitude relaxation rate similar to the response observed in current modulation.

A security-enhanced authentication with key agreement scheme for wireless mobile communications using elliptic curve cryptosystem

With the fast development of the Internet technology, there is an exponential growth in wireless networks-enabled applications across the globe. To ensure secure communication among all such applications, the authentication with key agreement has received maximum attention in recent times. Recently, Li et al. proposed an authentication with key agreement scheme using elliptic curve cryptosystem (ECC) for wireless mobile communications and claimed that their scheme could withstand different kinds of attacks. However, we find that their scheme cannot withstand various existing attacks. Also, their scheme suffers from the inefficiency of multiple secret keys. To improve security and performance, we propose a security-enhanced authentication with key agreement scheme using ECC for wireless mobile communications. Our analysis shows that the proposed scheme not only solves the security problems in Li et al.'s scheme, but also has better performance with respect to various selected metrics.

Precise-Orientation-Beamforming Scheme for Wireless Communications between Buoys

Utilizing wireless sensor network (WSN) to monitor the marine environment is one of the major techniques in oceanographic monitoring, and how to increase the limited communication distance between the buoys in WSN has become a hot research issue. In this paper, a new technique called precise-orientation-beamforming (POB) which uses the beamforming algorithm to increase the communication distance between buoys is presented. As was widely applied in the radar and sonar, the beamforming method was not used to extend the communication distance between buoys so far. The POB method overcomes the unstable position of buoys caused by waves by implementing the orientation filter. The whole process includes two steps: First, the real-time attitude of the antenna array is calculated by the orientation filter. With the known relative direction of the destination node to the antenna array, the second step is to control phased array antenna beamforming parameters, directing the beam at the destination node. The POB scheme has been simulated under the condition of regular waves. The results reveal that POB provides significant power gains and improves the distance between two communicating nodes effectively.

1.5 Gbit/s FPGA Implementation of a Fully-Parallel Turbo Decoder Designed for Mission-Critical Machine-Type Communication Applications

In wireless communication schemes, turbo codes facilitate near-capacity transmission throughputs by achieving reliable forward error correction. However, owing to the serial data dependencies imposed by the underlying logarithmic Bahl–Cocke-Jelinek–Raviv (Log-BCJR) algorithm, the limited processing throughputs of conventional turbo decoder implementations impose a severe bottleneck upon the overall throughputs of real-time wireless communication schemes. Motivated by this, we recently proposed a fully parallel turbo decoder (FPTD) algorithm, which eliminates these serial data dependencies, allowing parallel processing and hence offering a significantly higher processing throughput. In this paper, we propose a novel resource-efficient version of the FPTD algorithm, which reduces its computational resource requirement by 50%, which enhancing its suitability for field-programmable gate array (FPGA) implementations. We propose a model FPGA implementation. When using a Stratix IV FPGA, the proposed FPTD FPGA implementation achieves an average throughput of 1.53 Gb/s and an average latency of 0.56 $\mu \text{s}$ , when decoding frames comprising ${N}=720$ b. These are, respectively, 13.2 times and 11.1 times superior to those of the state-of-the-art FPGA implementation of the Log-BCJR long-term evolution (LTE) turbo decoder, when decoding frames of the same frame length at the same error correction capability. Furthermore, our proposed FPTD FPGA implementation achieves a normalized resource usage of 0.42 (kALUTs/Mb/s), which is 5.2 times superior to that of the benchmarker decoder. Furthermore, when decoding the shortest $N=40$ -b LTE frames, the proposed FPTD FPGA implementation achieves an average throughput of 442 Mb/s and an average latency of 0.18 $\mu \text{s}$ , which are, respectively, 21.1 times and 10.6 times superior to those of the benchmarker decoder. In this case, the normalized resource usage of 0.08 (kALUTs/Mb/s) is 146.4 times superior to that of the benchmarker decoder.

Smart Channel Sounder for 5G IoT: From Wireless Big Data to Active Communication

Internet-of-Things (IoT) will connect billions of smart devices and generate inundant data through prominent solutions, such as machine type communication. The Third Generation Partnership Project has launched the corresponding standards for multiple heterogeneous wireless smart devices in the long term evolution (LTE)/LTE-advanced. In the forthcoming years, the valuable information hidden in the deluge of data will be extracted and utilized in every field to improve quality and efficiency. However, the bottleneck of realizing this magnificent vista of future intelligent lives lies in how to satisfy the practical demands to transmit huge data volume through efficient wireless communication in diverse scenarios. Herein, multi-scenario wireless communication triggers critical problems in wireless channel modeling and soundings for 5G IoT, which by far, are understudied. In this paper, we introduce a general wireless channel model and its multiple up-to-date corresponding channel sounding methods for future 5G IoT green wireless communication. Through adopting the perspective of wireless big data excavation, the smart channel sounder transforms the traditional passive wireless communication scheme into an active expectation-guaranteed wireless communication scheme, which helps achieve efficient and green communication. To demonstrate the validity and efficiency of this smart sounder scheme, we make a compatible prototype testified in multiple scenarios. The multiple real-scenario experiments demonstrate that the smart sounder can function effectively, especially in those scenarios where traditional channel state information is not available or imperfect.

Improving the Tolerance of Stochastic LDPC Decoders to Overclocking-Induced Timing Errors: A Tutorial and a Design Example

Channel codes, such as low-density parity-check (LDPC) codes, may be employed in wireless communication schemes for correcting transmission errors. This tolerance to channel-induced transmission errors allows the communication schemes to achieve higher transmission throughputs, at the cost of requiring additional processing for performing LDPC decoding. However, this LDPC decoding operation is associated with a potentially inadequate processing throughput, which may constrain the attainable transmission throughput. In order to increase the processing throughput, the clock period may be reduced, albeit this is at the cost of potentially introducing timing errors. Previous research efforts have considered a paucity of solutions for mitigating the occurrence of timing errors in channel decoders, by employing additional circuitry for detecting and correcting these overclocking-induced timing errors. Against this background, in this paper, we demonstrate that stochastic LDPC decoders (LDPC-SDs) are capable of exploiting their inherent error correction capability for correcting not only transmission errors, but also timing errors, even without the requirement for additional circuitry. Motivated by this, we provide the first comprehensive tutorial on LDPC-SDs. We also propose a novel design flow for timing-error-tolerant LDPC decoders. We use this to develop a timing error model for LDPC-SDs and investigate how their overall error correction performance is affected by overclocking. Drawing upon our findings, we propose a modified LDPC-SD, having an improved timing error tolerance. In a particular practical scenario, this modification eliminates approximately 1-dB performance degradation that is suffered by an overclocked LDPC-SD without our modification, enabling the processing throughput to be increased by up to 69.4%, which is achieved without compromising the error correction capability or processing energy consumption of the LDPC-SD.

PAPR reduction scheme with efficient embedded signaling in MIMO-OFDM systems

Multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) is a promising transmission scheme for high performance broadband wireless communications. However, this technique suffers from a major drawback which is the high peak to average power ratio (PAPR) of the output signals. In order to overcome this issue, several methods requiring the transmission of explicit side information (SI) bits have been proposed in the literature. In fact, the transmitted bits must be channel-encoded as they are particularly critical to the performance of the considered OFDM system. Consequently, this channel-encoding highly increases the system complexity and decreases the transmission data rate. To overcome these problems, we propose in this paper two robust blind techniques that embed the SI implicitly into the OFDM frame. The first technique, referred to as Blind Space Time Bloc Codes (BSTBC), is inspired from the conventional selected mapping (SLM) approach. This technique banks on an adequate embedded signaling that mainly consists in a specific Space Time Bloc Codes (STBC) patterns and a precoding sequence codebook. In addition, in order to improve the signal detection process and the PAPR gain, we propose a new efficient combined Blind SLM-STBC (BSLM-STBC) method. Both methods propose an optimized scheme during the signal estimation process that is based on the maximum a posteriori (MAP) algorithm. A simulation study shows that our investigated approaches result in a spectacular PAPR reduction and furthermore lead to a perfect signal recovery at the receiver side.

A New Secure Authenticated Key Agreement Scheme for Wireless (Mobile) Communication in an EHR System using Cryptography

A New Secure Authenticated Key Agreement Scheme for Wireless (Mobile) Communication in an EHR System using Cryptography

An Efficient Security Scheme Authenticationand Encryption

Smart grid communication facilitate intelligent and distributed electric power transmission systems, but also introduces many security problems. In this paper the concept of dynamic secret is applied to design dynamic secret based authentication and encryption scheme for smart grid wireless communication. Between two parties of communication, the previous packets are coded as retransmission sequence, where retransmitted packet is marked as “1” and the other is marked as “0.” During the communication, the retransmission sequence is generated at both sides to update the dynamic encryption key. Any missing or misjudging in retransmission sequence would prevent the adversary from achieving the keys. In addition with this we introduce a new protocol, Integrated Authentication and Confidentiality (IAC), to provide efficient secure AMI communications in smart grid. With the help of IAC, an AMI(Advanced Metering Infrastructure) system can provide trust services, data privacy, and integrity by mutual authentications whenever a new smart meter initiates and joins the smart grid AMI network.

Energy efficient HARQ scheme for wireless communication over block fading channel

Energy efficiency (EE) can be enhanced by retransmissions and combining in hybrid automatic repeat request (HARQ) system. However, it is difficult to optimize the transmit power of each retransmission when the accurate retransmission number and future channel state information (CSI) cannot be obtained. This paper proposes a simple energy efficient HARQ scheme for point-to-point wireless communication. In the proposed scheme, the conditional word error rate (WER) of each retransmission is fixed and the transmit power is adapted Correspondingly. Three performance metrics are analyzed including average transmission number, throughput and EE. Compared with the conventional equal power HARQ scheme, the proposed scheme can significantly improve the EE and other two metrics under the same constraint of average transmit power or average energy consumption. Furthermore, it is found that, selecting a conditional WER which is slightly smaller than the optimal one is sufficient for practical implementation.

Navigation Data-Assisted Opportunistic Spectrum Scheduling for Network-Based UAV Systems: A Parallel Restless Bandits Formulation

A myriad of applications and services of information and communication technology (ICT) has been developed in the past decades, within which networks are the fundamental architecture to connect people and things. As one of the network-based ICT applications, recently, unmanned aerial vehicle (UAV) cooperation systems have attached much attention due to their successful applications in complex military and civilian missions. In this paper, we propose a navigation data-assisted optimal opportunistic spectrum access scheme for wireless communications in heterogeneous UAV networks, to achieve maximized long-term data rate by flexibly scheduling the spectrum subbands. Thanks to the navigation data that is always available locally at the entities in the network, rough prediction of wireless link quality can be obtained to assist subband allocations. Furthermore, to formulate the optimal spectrum scheduling problem, we develop a parallel restless bandits model, which can reduce the NP-hard optimization problem to simply selecting the link with the minimum index in the online stage. Extensive simulation results are also presented to demonstrate the significant performance improvement of the proposed scheme compared to the existing one.

Efficient Partial Single Relay Selection Scheme for Wireless Communications

Many wireless communication systems use a relay station for cooperative diversity or cell coverage extension. In this letter, an efficient partial single relay selection scheme is proposed for wireless communications. The conventional schemes such as the best harmonic mean and the threshold-based relay selection should know channel state informaion (CSI), or noise variance at all stations in advance. But the proposed scheme does not require any priori information. It uses a characteristic of the repeated signal pattern at candidates of the relay station. Simulation results show that the performance of proposed scheme is very close to the best harmonic mean relay selection scheme as one of the optimal relay selection schemes.

AREA EFFICIENT FRACTIONAL SAMPLE RATE CONVERSION ARCHITECTURE FOR SOFTWARE DEFINED RADIOS

The modern software defined radios (SDRs) use complex signal processing algorithms to realize efficient wireless communication schemes. Several such algorithms require a specific symbol to sample ratio to be maintained. In this context the fractional rate converter (FRC) becomes a crucial block in the receiver part of SDR. The paper presents an area optimized dynamic FRC block, for low power SDR applications. The limitations of conventional cascaded interpolator and decimator architecture for FRC are also presented. Extending the SINC function interpolation based architecture; towards high area optimization and providing run time configuration with time register are presented. The area and speed analysis are carried with Xilinx FPGA synthesis tools. Only 15% area occupancy with maximum clock speed of 133 MHz are reported on Spartan-6 Lx45 Field Programmable Gate Array (FPGA).

An Expedited WiFi Connection Establishment Scheme for Railroad Wireless Communications

Always on Internet service has become norm and people are able to enjoy anytime, anywhere broadband wireless communication services. With the emergence of smart phone and tablet, wireless network traffic has increased exponentially. Wireless network traffic is expected to continuously increase dramatically as more and more communication capable multimedia devices are expected to be connected to wireless network. In order to offload heavy traffic of cellular network, WiFi has chosen since WiFi normally operates in license exempt bands. 3rd Generation Partnership Program (3GPP) has started study item on 3GPPWiFi interworking in order to alleviate heavy traffic problem. Since WiFi is independent and different wireless technology, 3GPP needs to be specially designed to provide seamless and high quality interworking with WiFi. Long Term Evolution (LTE)-WiFi interworking has a technical challenge of WiFi network detection. A good solution should provide not only fast WiFi network detection but also battery power saving of mobile phones. In this paper, we propose LTE and WiFi interworking scheme for railroad wireless communication. Our solution is able to provide both expedited WiFi connection establishment and battery power saving by exploiting unique characteristics of railroad communication.