This paper considers channel estimation and system performance for the uplink of a single-cell massive multiple-input multiple-output system. Each receiver antenna base station is assumed to be equipped with pair one-bit analog-to-digital converters quantize real imaginary part received signal. We first propose an approach that applicable both flat frequency-selective fading, based on Bussgang decomposition reformulates nonlinear quantizer as linear function identical first- second-order...

This paper presents a novel and practical study on the position-based radio propagation channel for High-Speed Railway by performing extensive measurements at 2.35 GHz in China. The specification path loss model is developed. In particular, small scale fading properties such as K-factor, Doppler frequency feature time delay spread are parameterized, which show dynamic variances depending train location transceiver separation. Finally, statistical models firstly established to characterize...

In this letter, we investigate the downlink performance of massive multiple-input multiple-output (MIMO) systems where base station is equipped with one-bit analog-to-digital/digital-to-analog converters (ADC/DACs). We assume that employs linear minimum mean-squared-error channel estimator and treats estimate as true to precode data symbols. derive an expression for achievable rate matched-filter precoding. A detailed analysis resulting power efficiency pursued using our rate. Numerical...

Spatial characteristics of the propagation channel have a vital impact on application multi-antenna techniques. This paper analyzes angular and spatial correlation for high-speed railway (HSR) channels, based novel moving virtual antenna array (MVAA) measurement scheme. The principle MVAA scheme is deeply investigated further verified by theoretical geometry-based stochastic model. Using scheme, single-input multiple-output (SIMO) impulse response data are derived from single-antenna...

The widespread popularity of high-speed railways (HSRs) urges a critical demand on high-data-rate railway communication services for both train operation and passenger experience. To satisfy the ever-increasing requirements, future HSR systems, such as long-term evolution (LTE-R), fifth generation (5G) HSR, 5G (5G-R), corresponding transmission technologies, e.g., mobile relay, coordinated multipoint, massive multiple-input multiple-output (MIMO), millimeter-wave (mmWave), have recently...

Channel measurements are the prerequisite condition for design of next-generation high-speed railway (HSR) communication system. Because measurement restriction and efficiency issues applying conventional channel sounders in HSR scenarios, railway-network-based becoming quite attractive. In this paper, a method that employs cell-specific reference signal long-term-evolution (LTE) networks as excitation to perform is presented. This implemented by novel system composed existing LTE dedicated...

High-speed railway (HSR) communications have recently attracted much attention due to some specific needs, such as passenger experience services, business process support and operational data voice services. The HSR radio channel, a basis for the design of communication systems evaluation technologies, has not yet been sufficiently investigated. This article focuses on channel sounding techniques future systems. Emphasis is placed fundamental features measuring review state art in...

The performance of distributed communication systems is commonly subject to the cross-correlation characteristics multi-link channels. In this paper, we concentrate on modeling small-scale fading (SSF) channels in high-speed train (HST) networks with base stations according classical geometry-based stochastic model (GBSM). To appropriately describe a propagation scenario HST network, novel geometrical considering line-of-sight component, single-bounced one-ring model, and double-bounced...

In the RFID systems, tag collision arbitration is a significant issue for fast identification. This paper presents analysis and simulation of several anti-collision algorithms. algorithms, ALOHA binary tree algorithms are most widely used. The achieved by using C#.NET. simulation, EPC Class1 Class Generation2 protocols chosen to be criterions two Finally some results listed. According between different an advanced DFSA algorithm based on grouping method proposed.

Background Systemic sclerosis (SSc) is a rare autoimmune disease, and WeChat major source of health information in China. This study assesses the quality SSc on to understand its impact public knowledge engagement. Methods A total 375 articles from 9 accounts were systematically analyzed using DISCERN Global Quality Scale (GQS) tools. Article was evaluated based credibility, content accuracy, user engagement, including metrics such as views, likes, comments. Results Individual authors posted...

Capacitor-couple technique used to lower snapback-trigger voltage and ensure uniform ESD current distribution in deep-submicron CMOS on-chip protection circuit is proposed. The coupling capacitor realized by a poly layer right under the wire-bonding metal pad without increasing extra layout area pad. A timing-original design model has been derived calculate capacitor-couple efficiency of this proposed circuit. Using circuit, thinner gate oxide devices low-voltage ASIC can be effectively protected.

There is an increasing demand on wireless communications in subway tunnels to provide video surveillance and sensory data for security, maintenance train control, offer various communication or entertainment services (e.g., Internet, etc.) passengers as well. The channel quite unique due the confined space waveguide effects. Therefore, modeling radio characteristics critically important systems design optimization. This paper investigates key of a tunnel at 2.4 GHz 5 GHz, such path loss,...

This paper considers channel estimation and achievable rates for the uplink of a massive multiple-input multiple-output (MIMO) system where base station is equipped with one-bit analog-to-digital converters (ADCs). By rewriting nonlinear quantization using linear expression, we first derive simple insightful expression minimum mean-square-error (LMMSE) estimator. Then employing this estimator, closed-form lower bound rate maximum ratio combiner (MRC) receiver. Numerical results are presented...

This paper proposes a multi-feature fusion based propagation scene recognition model for high-speed railway (HSR) channels and presents the channel relevance analysis of HSR scenes. Extensive field measurement data in typical scenes, including rural, station, suburban multi-link are collected with assist long-term evolution (LTE) networks. The datasets space-time-frequency features, involving Ricean K-factor, root mean square delay spread, Doppler angle generated training testing as well...

The paper describes the measurement campaigns for broadband channel properties under high- speed condition, which have been carried out on Zhengzhou to Xi'an (ZX) High-Speed Railway and Beijing Tianjin (BT) Railway. WCDMA with bandwidth of 3.84MHz is employed as excitation signal that transmitted from base station along railway received by TSMQ ROHDE & SCHWARZ inside train. Different scenarios including plain, U-shape cutting, hilly terrain are chosen in measurements parameters about...

This study proposes a stochastic channel model based on the propagation graph theory for high‐speed railway (HSR) cutting scenarios. Single‐input single‐output wideband measurements are conducted under acquiring realistic data. The covering line of sight, single bounced and double conditions is used to describe measured scenario generate virtual impulse responses. validated focusing small‐scale characteristics such as Ricean K‐factor, delay frequency dispersions, close agreement achieved...

The performance of wireless systems and transmission technologies is ultimately limited by radio channels. This paper characterizes multi-link multiple-input multiple-output (MIMO) channels for future high-speed train (HST) communication systems. channel characterization based on field measurements in a dedicated long-term evolution (LTE) network along railway line China. raw data are collected an LTE sounder with two antenna ports the region between neighboring remote units network, which...

This paper presents the analysis of short-term fading behavior in high-speed railway (HSR) communication networks, based on passive channel measurements. A long-term evolution (LTE)-based sounding system is used to measure propagation characteristics a dedicated HSR LTE network with multiple scenarios, such as rural, station, and suburban, echo effect (ECE) caused by same signaling from different remote radio units. The measurement data are partitioned into four cases, involving rural ECE,...

There are a lot of handovers failed in high-speed mobile environment because the handover can't be completed time although field strength values sufficient availability along tracks. A relay based fast scheme is proposed which suitable for environment. Two reference points introduced to ensure time. Pre-preparation and packet bi-casting reduce communication interruption realize seamless handover. The performance analyzed terms delay,

Massive multiple input and output (MIMO) systems can increase the spectrum energy efficiency of existing cells, because this, massive MIMO has been considered as a potential technique for next generation wireless communication networks. Since thorough knowledge propagation channel is prerequisite reliable systems, channels are great current interest. However, few investigations have done on channels, especially angle properties. In this paper, based realistic measurement in typical stadium...

This paper presents a multiple frequency bands-switching scheme for wideband channel sounding, which is able to extend the overall sounding bandwidth without changing operation of hardware. It especially suitable low mobility and high data-rate scenarios (e.g., indoor hot spot) in fifth generation mobile communication systems. With this scheme, sounder developed on software-defined radio platform that employs an orthogonal division multiplexing signal at 5.6 GHz. In each cycle, ten...

Coordinated multipoint (CoMP) and massive multiple-input multiple-output (mMIMO) are two of promising technologies in future intelligent high-speed railway (HSR) communication systems, whose performance is fundamentally determined by the characteristics cooperative mMIMO channels. This article proposes a dynamic three-dimensional (3-D) wideband geometry-based stochastic model (GBSM) for HSR The proposed GBSM employs sphere elliptic-cylinder models to describe common uncommon clusters...

An efficient channel sounding method using cellular communication systems is proposed for high-speed railway (HSR) propagation environments. This measurement technique can be used conveniently to characterize different HSR scenarios, which significantly improve the efficiency. Based on downlink signals of wideband code division multiple access (WCDMA) and long term evolution (LTE), principles methodologies are presented. Using WCDMA signal, a campaign conducted in real-world scenarios...

A semiempirical multiple-input multiple-output (MIMO) channel model is proposed for high-speed railway (HSR) viaduct scenarios. The MIMO based on the combination of realistic single-input single-output (SISO) measurement results and a theoretical geometry-based stochastic (GBSM). Temporal fading characteristics involving<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:mi>K</mml:mi></mml:mrow></mml:math>-factor Doppler power spectral density (PSD) are derived...