Short-range Wireless Communication Systems Research Articles

A Compact 60GHz Power Amplifier in 65nm CMOS Technology

A compact 60GHz power amplifier chip in 65nm CMOS technology of three-stage common source structure is presented. The first two amplifiers offer sufficient gain to pre-amplify the small input power. The third stage amplifier uses two sets of differential pairs to achieve power synthesis. On-chip transformer coupling is adopted to realize inter-stage impedance matching as well as input and output matching. The compact structure of on-chip transformer can reduce the chip size and improve the integration degree. The measured small signal gain at 60GHz of 22.3dB, the saturation power of 20.2dBm, the output P-1dB of 17.3dBm, the PAE of 14%, and the core area is 0.19mm2. The power amplifier can be used in high-speed short-range wireless communication system to enhance communication data transmission capacity.

Secure Visible Light Communication System via Cooperative Attack Detecting Techniques

With the recent development of fourth industrial technology, the need for a broadband short-range wireless communication system to realize an ultraconnected, ultra-low latency, and ultra-realistic intelligent information society has emerged. Among the next-generation communication network technologies that can fulfill the technical demands, visible light communication (VLC) is a promising technology that can use illuminated light as a communication light source, which is convenient and environmentally friendly and has high energy and frequency efficiency. However, although VLC has a high level of security owing to the straightness and transparency of visible light, if some of the VLC nodes in a dense mesh network environment are hacked by external attacks, there can be critical performance degradation by jamming attacks. Although several studies have suggested the possibility of VLC jamming attacks, only a few have studied how to effectively detect and respond to these attacks. This study proposes a method to collaboratively detect and respond to jamming attacks in smart LED-based VLC systems. According to the experimental results of this study, the proposed cooperative method showed 91% attack detection accuracy and 1.82 times better than the k-random method. The proposed method showed a minimum detection rate of 84% even in an obstacle-rich environment, proving outstanding attack detection performance 1.68 times better than the k-random method.

LED-to-LED wireless communication between divers

<p class="Abstract">For military divers, having a robust, secure, and undetectable wireless communication system available is a fundamental element. Wireless intercoms using acoustic waves are currently used. These systems, even if reliable, have the defect of being easily identifiable and detectable. Visible light can pass through sea water. Therefore, light can be used to develop short-range wireless communication systems. To realize secure close-range underwater wireless communication, the Underwater Optical Wireless Communication (UOWC) can be a valid alternative to acoustic wireless communication. UOWC is not a new idea, but the problem of the presence of sunlight and the possibility of using near-ultraviolet radiation (near-UV) has not been adequately addressed in the literature yet. In military applications, the possibility of using invisible optical radiation can be of great interest. In this paper, a feasibility study is carried out to demonstrate that UOWC can be performed using near-ultraviolet radiation. The proposed system can be useful for wireless voice communications between military divers as well as amateur divers.</p>

High efficiency unslotted ultra-wideband microstrip antenna for sub-terahertz short range wireless communication systems

A sub-terahertz (THz) band microstrip antenna is proposed in this paper, which has an unslotted, easy to fabricate design. The presented antenna has a wide impedance bandwidth of 0.114 THz (from 0.093 THz to 0.207 THz), where S11≤−10dB. It also has a wide fractional bandwidth percentage of 76%. Once the computer simulations are performed, it is observed that the antenna has a maximum radiation efficiency of 98% throughout the operating frequency range. Moreover, it has an omni-directional radiation character and has a compact size of 1000 × 1000 × 100 µm3 (0.31λ × 0.31λ × 0.031λ, where λ is the wavelength at the lowest operating frequency). Finally, the 2 × 2 multi-input multi-output (MIMO) version is analyzed and the isolation between the elements is determined as less than − 17 dB across the band of operation. With all the abovementioned features, the proposed antenna outperforms from most of other state-of-arts and indicates that it is a suitable candidate for short range sub-THz applications.

A Compact UWB Bandpass Chip Filter on a GaAs Substrate with Modified Chebyshev Structure

Ultra-Wideband (UWB) systems are widely used in low-power, high-speed, high-security short-range wireless communication systems throughout digital homes and offices. In the RF front-end of a UWB system, bandpass filters (BPFs) are used to put through the passband signals and reject the stopband signals. Most UWB BPFs are designed with dielectric materials on circuit boards or LTCC technology. In this paper, a very compact fully integrated UWB chip filter is proposed and designed on a GaAs substrate with nitride as dielectric layers to meet the small size requirement of portable devices for next-generation UWB applications. The filter is constructed with a modified Chebyshev structure. The final filter circuit contains only four inductors instead of six for the conventional Chebyshev filter, which makes the chip more compact and cost effective. The filter is designed and fabricated on a 0.25 μm GaAs pHEMT technology with a chip size of only 0.73 mm × 0.51 mm including the chip edge and scribe line area, while the filter core area is only 0.61 mm × 0.39 mm, including bonding PADs. The measurement results illustrated that the proposed BPF shows a passband covering the frequency range of 3.1–9.0 GHz, the minimum passband insertion loss is only 1.5 dB, the stopband rejection is better than −30 dB throughout frequencies below 2 GHz and above 12 GHz, S11 is less than −16 dB, and S22 is better than −11 dB during the whole passband range. It demonstrated that the proposed filter can be considered as one of the most compact UWB filters.

Complex-Valued Neural Networks for Noncoherent Demodulation

Noncoherent demodulation is an attractive choice for many wireless communication systems. It requires minimal protocol overhead for carrier synchronization, and it is robust to radio impairments commonly found in low-cost transceivers. Machine learning techniques, such as neural networks and deep learning, offer additional benefits for these systems. Practical communication systems often include nonlinearities, non-stationarity, and non-Gaussian noise, which complicate mathematical derivation of optimum demodulators. Learning approaches can optimize demodulator performance directly from simulated or measured radio data, which is often plentiful in the design and verification of today’s integrated transceivers. This paper examines several candidate neural network topologies for use in noncoherent demodulation and provides a mathematical framework for their comparison. Each is based on a complex-valued feature detection layer, which may be characterized as coherent or noncoherent, followed by one or more real-valued classification layers. Backpropagation equations for the noncoherent feature layer include a synchronization term that facilitates training with noncoherent input data. The coherent layer does not synchronize training data, however a noncoherent demodulator can still be constructed by increasing the coherent layer capacity and adding a max pooling layer to marginalize the unknown signal phase. A frequency classification example highlights the differences between the topologies and confirms that optimum noncoherent demodulation can be learned in the presence of AWGN and random phase offsets. The topologies considered here are suitable for noncoherent demodulation of power-efficient modulations such as FSK and ASK, which are typical in today’s short-range wireless communication systems. It is hoped that such topologies will lead to a future common architecture that can support the wide range of modulation formats in this space.

A Dual Interference-Canceling Active Quasi-Circulator Achieving 36-dB Isolation Over 6-GHz Bandwidth

Circulator is a key component in full-duplex wireless and radar detection systems. In this letter, a dual interference-canceling active quasi-circulator is proposed to enhance the isolation capability over the range of 1–7 GHz. The circulator is fabricated in the standard 0.18- $\mu \text{m}$ CMOS process occupying 1.03 mm $\times0.55$ mm including the pads. Measurement results demonstrate more than 36-dB isolation from the Tx to the Rx within 6-GHz bandwidth. The designed circulator is a good candidate for duplexers to allow the integrated transmitter and receiver to share a single antenna in the certain short-range wideband wireless communication systems, where noise figure (NF) is not strictly demanded but low cost and high integration are urgently required.

Modeling and Analysis of Wearable Antennas

This paper describes a sheet-like transmission line for constructing a short-range wireless communication system using flexible materials such as clothing. As a new application of wireless communications, it is desired to construct a Personal Area Network (PAN) and a sensor network with a short distance communication area of about 1 m to 2 m. For such applications, a waveguide of a new structure is required which can exchange information at an arbitrary place on the waveguide, which has a flexible structure and limits the area for wireless communication. Therefore, by disposing the microstrip type resonators two-dimensionally with a two-layer structure and electromagnetically strongly coupling the resonators, the electromagnetic waves are confined well within the transmission line, and the antenna of the wireless device resonator is arranged. Furthermore, by constructing this transmission line with a sheet-like flexible wearable material, the transmission of both information and power can be performed through a thin flexible transmission line for the wearable network.

Demonstration of 60 GHz millimeter-wave short-range wireless communication system at 3.5 Gbps over 5 m range

Millimeter-wave communication has received considerable attention for use in new-generation broadband wireless communication because of the scarcity of microwave band spectrum resources. The unlicensed frequency band at 60 GHz is suitable for indoor short-range broadband communication. In this paper, we introduce a 60 GHz millimeter-wave short-range wireless communication demo system adhering to the IEEE 802.11ad standard and targeting high-definition video streaming transmission. The system uses single-carrier transmission with frequency-domain equalization. The hardware prototype consists of a 65-nm CMOS radio-frequency front-end and a baseband transceiver for the physical layer functions. Important baseband technologies such as carrier synchronization, phase noise compensation, frequency-domain equalization, and low-density parity-check decoding based on probability calculation are also discussed. The system performance is demonstrated in an experiment on high-definition video transmission, where a data rate of 3.52 Gbps is achieved with a quadrature phase-shift keying signal over a distance of 5.109 m.

ZigBee를 적용한 누전상태 모니터링시스템 구현

최근 가정이나 산업용 건물에서 컴퓨터, TV, 냉장고, LED 조명 등 가전기기들의 누전전류에 의한 감전사고가 지속적으로 발생하고 있다. 그리고 가정 내 벽면에 설치된 콘센트에 직접 연결되어 제어 하는 누전차단 모듈들은 모듈 후단에 병렬로 연결된 각각의 가전기기들의 누전상태를 확인하기가 쉽지 않다. 또한 전류가 정상적인 전류의 통로 이외로 흐르는 누전전류를 기존의 누전차단기들은 배전함에 설치되어 누전시 전원을 차단해 주는 역할 을 한다. 가전기기의 누전으로 인한 감전, 화재 등 여러 가지 재해가 발생하여 누전전류의 위험성이 심각하게 제시되고 있다. 이에 근거리 무선통신시스템 중에서 저전력과 저가격 면에서 장점이 많은 IEEE 80215.4 기반의 지그비통신을 이용하여 상시 감시할 수 있는 누전상태 모니터링시스템 구현방안을 제시한다. In recent years, electric shock accidents due to electric leakage currents of household appliances such as computers, TVs, refrigerators, and LED lights are continuously occurring in homes and industrial buildings. And it is not easy to check the leakage current of each household appliances connected in parallel at the rear end of the module. In addition, the leakage current flowing through the path of the normal current other than the existing current leakage circuit breakers are installed in the distribution box, only the function to cut off the power when the leakage. Therefore, there are various disasters such as electric shock and fire caused by short circuit of household appliances, and the risk of such leakage current is seriously presented. In this paper, we propose a method to implement a leakage monitoring system that can be monitored at all times using Zigbee communication based on IEEE 80215.4, which has advantages in low power and low cost among short range wireless communication systems.

A New Multi-user Ultra Wide Band System Based on Modified Gegenbauer Functions and M-OAM Modulation for Communication of Intelligent Transportation Systems

Ultra-wideband technology is based on the transmission of very short pulses with relatively low energy, which make it a promising option for short range wireless communication system. In this paper, we propose to use this technology to establish a new multi-user technique dedicated to intelligent transport systems, especially vehicle-to-vehicle and vehicle-to-infrastructure communications. Indeed, the design of such system must provide good quality of service for a large number of users simultaneously and with high data rate. The proposed system is based on the use of a new modulation schemes named orthogonal amplitude modulation to reach high data rate; and an original multiple access technique that allows a maximum number of users simultaneously with good performances.

Millimeter-Wave Wireless LAN and Its Extension toward 5G Heterogeneous Networks

Millimeter-wave (mmw) frequency bands, especially 60 GHz unlicensed band, are considered as a promising solution for gigabit short range wireless communication systems. IEEE standard 802.11ad, also known as WiGig, is standardized for the usage of the 60 GHz unlicensed band for wireless local area networks (WLANs). By using this mmw WLAN, multi-Gbps rate can be achieved to support bandwidth-intensive multimedia applications. Exhaustive search along with beamforming (BF) is usually used to overcome 60 GHz channel propagation loss and accomplish data transmissions in such mmw WLANs. Because of its short range transmission with a high susceptibility to path blocking, multiple number of mmw access points (APs) should be used to fully cover a typical target environment for future high capacity multi-Gbps WLANs. Therefore, coordination among mmw APs is highly needed to overcome packet collisions resulting from un-coordinated exhaustive search BF and to increase the total capacity of mmw WLANs. In this paper, we firstly give the current status of mmw WLANs with our developed WiGig AP prototype. Then, we highlight the great need for coordinated transmissions among mmw APs as a key enabler for future high capacity mmw WLANs. Two different types of coordinated mmw WLAN architecture are introduced. One is the distributed antenna type architecture to realize centralized coordination, while the other is an autonomous coordination with the assistance of legacy Wi-Fi signaling. Moreover, two heterogeneous network (HetNet) architectures are also introduced to efficiently extend the coordinated mmw WLANs to be used for future 5 Generation (5G) cellular networks.

Training Sequence Design for NBI Mitigation in Compressive Sensing UWB Systems

Ultra wideband (UWB) is a promising technology in delivering high data rate for short range wireless communication systems. Because of their large bandwidth, UWB signals may encounter some problems especially with high sampling rate requirements. Moreover, coherence existence with other narrowband systems is a major concern which needs to be addressed through proper mechanisms. The problem becomes so complex if multiple users exist. Since narrowband interference (NBI) signals have sparse representation in the discrete cosine transform (DCT) domain, they can be estimated and suppressed using Compressive Sensing (CS). CS also has the ability to reduce the high sampling rate requirements. For training based NBI mitigation with CS, three groups of pilot symbols are used to estimate the NBI signal subspace, the UWB signal subspace, and to provide information about the channel. In this paper, the distribution of pilot symbols among the three groups is investigated in the presence of strong NBI. The investigation is based on the bit error rate performance and throughput. The influence of each pilot symbols group is studied. The performance is also evaluated in the presence of multiuser interference in addition to the NBI. Simulation results show that the size of the third group of pilot symbols which is used to estimate the channel is the most dominant one.

Mutual Distance Bounding Protocol with Its Implementability Over a Noisy Channel and Its Utilization for Key Agreement in Peer-to-Peer Wireless Networks

In order to protect a wireless sensor network and an RFID system against wormhole and relay attacks respectively, distance bounding protocols are suggested for the past decade. In these protocols, a verifier authenticates a user as well as estimating an upper bound for the physical distance between the user and itself. Recently, distance bounding protocols, each with a mutual authentication, are proposed to increase the security level for such systems. They are also suggested to be deployed for key agreement protocols in a short-range wireless communication system to prevent Man-in-the-Middle attack. In this paper, a new mutual distance bounding protocol called NMDB is proposed with two security parameters ( $$n$$ n and $$t$$ t ). The parameter $$n$$ n denotes the number of iterations in an execution of the protocol and the parameter $$t$$ t presents the number of errors acceptable by the verifier during $$n$$ n iterations. This novel protocol is implementable in a noisy wireless environment without requiring final confirmation message. Moreover, it is shown that, how this protocol can be employed for the key agreement procedures to resist against Man-in-the-Middle attack. NMDB is also analyzed in a noisy environment to compute the success probability of attackers and the rejection probability of a valid user due to channel errors. The analytically obtained results show that, with the proper selection of the security parameters ( $$n$$ n and $$t$$ t ) in a known noisy environment, NMDB provides an appropriate security level with a reliable performance.

Bonding Wire Loop Antenna in Standard Ball Grid Array Package for 60-GHz Short-Range Wireless Communication

High-speed short-range wireless communication systems are expected to utilize the 60-GHz band. This paper presents a bonding wire loop antenna in a standard ball grid array (BGA) package for 60-GHz short-range wireless communication. The proposed antenna has a loop shape and consists of two bonding wires connecting to a complementary metal-oxide-semiconductor (CMOS) chip and a metal plate on an interposer in a BGA package. The antenna can be fabricated at low cost by a conventional BGA package fabrication process. The BGA package is mounted on a printed circuit board (PCB) that consists of resin substrate, such as FR-4. The broadband impedance characteristic is achieved by adjusting the position of the metal pad for wire bonding. The antenna gain is improved by forming cranked ledges and notches in the metal patterns of the PCB, and the wide-angle radiation characteristic is realized. The sizes of the fabricated antenna and BGA package are approximately 0.6 mm × 1.0 mm × 0.3 mm and 9.0 mm × 9.0 mm × 0.9 mm, respectively. Performing measurements, the antenna gain with the PCB is from - 2.4 to 4.9 dBi over the 57- to 65-GHz frequency range and over an angular range of 60 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> in the horizontal plane.

Graphene radio: Detecting radiowaves with a single atom sheet

We present the experimental evidence of RF demodulation by a graphene monolayer embedded in a coplanar structure. The demodulator was tested in the frequency range from 100 MHz to 25 GHz using amplitude modulated input signals. An input power of 0 dBm (1 mW) was used, which is the typical power emitted for short range wireless communication systems, such as Bluetooth. The graphene demodulator exhibits good signal responsivity in the frequency range associated to industrial, scientific and medical radio band with a peak of 1100 V/W at 3.5 GHz.

A novel printed monopole antenna for future ultra-wideband communication systems

In this letter, a novel microstrip line-fed printed monopole antenna for ultra-wideband (UWB) short-range wireless communications is proposed. The proposed antenna consists of a trapezoidal-shaped patch with two elliptical-shaped cuts from its edge forming a bell-shaped cut. Experimental results shows that the designed antenna operates over impedance bandwidth 3.2–11.4 GHz for return loss S11 < −10 dB, which almost covering the UWB frequency bandwidth. Moreover, the antenna has a good omnidirectional radiation patterns in the H-plane with good gain flatness over the frequency range of interest. The antenna transmission characteristics at different receiving angles are also measured. By embedding a simple narrow U-shaped slot in the radiating microstrip patch, a notch in the frequency band of 5.0–6.0 GHz is obtained. The proposed antenna is considered a good candidate for UWB short-range wireless communication systems avoiding the interference of the existing wireless systems. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26113

SIZE REDUCTION AND BANDWIDTH ENHANCEMENT OF A UWB HYBRID DIELECTRIC RESONATOR ANTENNA FOR SHORT-RANGE WIRELESS COMMUNICATIONS

In this paper, a novel hybrid dielectric resonator (DR) antenna for Ultrawideband (UWB) short-range wireless communications is proposed. The proposed antenna consists of a microstrip fed monopole loaded with a half cylindrical dielectric resonator antenna of Rogers RO3010 mounted on RT5880 substrate with a flnite ground plane. The microstrip line fed monopole antenna is on the other side of the substrate. Compared to the conventional circular cylindrical DR mounted on a flnite ground plane (reference antenna), the proposed antenna has a reduction in the antenna size by about 30% with a bandwidth increase by about 22% than the reference antenna. The proposed antenna has a good impedance bandwidth. In addition, the proposed antenna has a quite higher and more stable gain than that of reference antenna. Moreover, the antenna has a good omni-directional radiation patterns in the H-plane. The proposed antenna is considered a good candidate for UWB short-range wireless communication systems.

테라헤르츠 대역 주파수에서 근거리 무선 통신 응용을 위한 채널 모델 및 무선 링크 성능 분석

본 논문에서는 현재 주목을 받고 있는 테라헤르츠 대역의 주파수에서 근거리 무선 통신 응용을 위한 채널 모델과 무선 링크의 성능 분석에 대하여 서술한다. 10 Gbps 이상의 전송 속도를 실현하기 위해서는 주파수 대역폭이 기존의 밀리미터파에서 사용하는 주파수 대역폭보다 더 넓은 대역폭이 필요하며, 이 대역폭을 얻기 위해서는 테라헤르츠 주파수 대역으로 자연적으로 옮겨가지 않을 수 없다. ITU-R P.676-7 모델을 이용하여 테라헤르츠 대역의 대기 전파 감쇠 특성 분석 결과, 중심 주파수 220, 300, 350 GHz에서 약 68, 48, 45 GHz의 주파수 대역폭이 가용하며, 스펙트럼 효율이 1 이하인 변조 방식으로도 10 Gbps 이상의 데이터 속도를 얻을 수 있음을 시뮬레이션을 통하여 확인하였다. 간략화 PDP 모델을 이용하여 실내 공간의 건물 재질에 따른 지연 특성을 분석하였다. 실내 공간의 크기 <TEX>$6\;m(L){\times}5\;m(W){\times}2.5\;m(H)$</TEX>에서 콘크리트 벽의 경우 TE 편파에서 RMS 지연 확산은 9.23 ns였다. 이 결과는 참고문헌의 Ray-Tracing 시뮬레이션에서 얻은 10 ns 이내에 근접한다. 옥내 무선 링크 성능 분석 결과, 수신기의 감도는 BPSK 변조 방식을 사용하는 경우 대역폭 <TEX>$5{\sim}50\;GHz$</TEX>에 대하여 <TEX>$-56{\sim}-46\;dBm$</TEX>이고, 안테나 이득은 10 m 링크에서 <TEX>$26.6{\sim}31.6\;dBi$</TEX>였다. AWGN 채널과 LOS 환경을 가정할 때 송신기 출력 -15dBm에서 캐리어 주파수 220, 300, 350 GHz일 때 최대 달성 가능한 데이터 속도는 각각 30, 16, 12 Gbps였다. 이 결과는 BPSK 변조 방식을 사용하여 1 m 링크에서 얻은 결과이다. BER은 <TEX>$10^{-12}$</TEX>으로 가정하였고, 송신기 출력을 증가시키면 더욱 높은 데이터 속도를 얻을 수 있다. In this paper, channel model and wireless link performance analysis for the short-range wireless communication system applications in the terahertz frequency which is currently interested in many countries will be described. In order to realize high data rates above 10 Gbps, the more wide bandwidths will be required than the currently available bandwidths of millimeter-wave frequencies, therefore, the carrier frequencies will be pushed to THz range to obtain larger bandwidths. From the THz atmospheric propagation characteristics based on ITU-R P.676-7, the available bandwidths were calculated to be 68, 48 and 45 GHz at the center frequencies of 220, 300 and 350 GHz, respectively. With these larger bandwidths, it was shown from the simulation that higher data rate above 10 Gbps can be achieved using lower order modulation schemes which have spectral efficiency of below 1. The indoor propagation delay spread characteristics were analyzed using a simplified PDP model with respect to building materials. The RMS delay spread was calculated to be 9.23 ns in a room size of <TEX>$6\;m(L){\times}5\;m(W){\times}2.5\;m(H)$</TEX> for the concrete plaster with TE polarization, which is a similar result of below 10 ns from the Ray-Tracing simulation in the reference paper. The indoor wireless link performance analysis results showed that receiver sensitivity was <TEX>$-56{\sim}-46\;dBm$</TEX> over bandwidth of <TEX>$5{\sim}50\;GHz$</TEX> and antenna gain was calculated to be <TEX>$26.6{\sim}31.6\;dBi$</TEX> at link distance of 10m under the BPSK modulation scheme. The maximum achievable data rates were estimated to be 30, 16 and 12 Gbps at the carrier frequencies of 220, 300 and 350 GHz, respectively, under the A WGN and LOS conditions, where it was assumed that the output power of the transmitter is -15 dBm and link distance of 1 m with BER of <TEX>$10^{-12}$</TEX>. If the output power of transmitter is increased, the more higher data rate can be achieved than the above results.

Direct Blind Adaptive MOE Receiver for PAM Modulated Time-Hopping UWB System Over Frequency-Selective Fading Channel

Ultra wideband impulse radio systems have attracted great attention for their promised applications in high-speed short-range indoor wireless communication systems. Among the various modulation and multiple access schemes, this paper deals with time-hopping (TH) antipodal pulse amplitude modulation operating in the presence of a multipath fading downlink channel. We first employ a constrained optimization technique to design a batch mode blind (without exploiting training sequences and undesired users’ time-hopping (TH) codes) mobile station receiver. To reduce the computational complexity, we propose a blind adaptive receiver that is based on the criterion of maximizing the receiver’s minimum possible output energy. The algorithm jointly and iteratively optimizes the weight vector and channel impulse response to improve system performance. Simulation results show that the proposed adaptive receiver converges to the optimum batch mode receiver. Moreover, the algorithms are shown to be robust to multi-user interference and near-far problems.