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在战术通信环境下,机动车载平台间的无线信道特性更加复杂。传统移动信道模型没有考虑战术场景下的特殊因素对车对车信道的影响,所以此类模型不能应用于战术车载通信系统的设计和优化。为解决传统移动信道模型的局限性,该文提出一种适用于战术通信环境的车对车(Tactical-Vehicle-to-Vehicle, T-V2V)信道模型。该模型充分考虑了实际战术场景中两个车载平台间相互运动、方向性天线的对准问题以及地形地貌等因素对车对车信道的影响,并基于电平通过率(Lever Crossing Rate, LCR)和平均衰落持续时间(Average Duration of Fading, ADF)指标对所提模型进行统计分析。仿真结果表明,所提模型更加贴合战术通信实际情况,能够更为准确地反映出战术通信环境下的车对车信道的变化特性。最后,该文对影响T-V2V信道模型的相关因素进行了仿真分析,所得结果对战术车载通信系统的物理层设计具有重要参考价值。 相似文献
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文中提出了一种时变宽带MIMO信道的建模方法。该方法利用修正的Jakes衰落模型,用正弦波形叠加的方法,建立了一个频率选择性瑞利衰落多普勒MIMO信道模型。MATLAB仿真证实了该方法的可行性。 相似文献
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针对指向性天线所造成的覆盖区域面积是非对称特点,建立了非对称空间分布的空间统计信道模型,并且提出两种情况,一种是移动接收台(MS,Mobile Station)在覆盖区域内,另一种是移动接收台MS不在覆盖区域内。利用统计分析的方法,通过推导计算出在此空间统计信道模型下的到达时间(TOA, Time of Arrival)概率分布密度函数。实验仿真结果表明本模型的信道参数估计结果符合理论和经验,拓展了空间统计信道模型的研究和应用。 相似文献
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Techniques for modeling and simulating channel conditions play an essential role in understanding network protocol and application behavior. In [11], we demonstrated that inaccurate modeling using a traditional analytical model yielded suboptimal error control protocol parameters choices. In this paper, we demonstrate that time-varying effects on wireless channels result in wireless traces which exhibit non-stationary behavior over small window sizes. We then present an algorithm that extracts stationary components from a collected trace in order to provide analytical channel models that, relative to traditional approaches, more accurately represent characteristics such as burstiness, statistical distribution of errors, and packet loss processes. Our algorithm also generates artificial traces with the same statistical characteristics as actual collected network traces. For validation, we develop a channel model for the circuit-switched data service in GSM and show that it: (1) more closely approximates GSM channel characteristics than traditional Markov models and (2) generates artificial traces that closely match collected traces' statistics. Using these traces in a simulator environment enables future protocol and application testing under different controlled and repeatable conditions. 相似文献
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Nielsen Jesper Ødum Afanassiev Valentine Bach Andersen JØrgen 《Wireless Personal Communications》2001,19(2):91-120
This paper proposes a new approach to modeling the radio channel experienced by transceivers moving in an indoor environment. For modeling the time-varying impulse response (IR) a randomly time-varyingpower-delay profile (PDP) is used, which enables the use of PDPs specific to local environments while widely different environments still can be included in the model. The PDPs are expanded in terms of so-called cluster functions modeling ray scattering on major physical objects in the environment. By using random weighting of the cluster functions, transceiver movements in some imaginary environment is modeled. In addition to the new model, the paper also presents results obtained from measurements of the indoor channel. A good agreement is found between measurement and model data, and thus the concepts applied in the new model seem to be useful in practice. 相似文献
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A novel transformer-type variable inductor is proposed to achieve a wide tuning range at frequencies as high as K band. The variable inductor is designed, and an intuitive model is built to analyze its performance by HFSS. A lot of mathematical analysis is done in detail. A VCO using the proposed variable inductor is designed with TSMC 0.13 μm CMOS technology for verification. The frequency tuning range of the VCO depends on the proposed variable inductor. The phase noise of the VCO depends on the quality of the LC tank (including the proposed variable inductor and varactors). So a specific AMOS varactor is implemented to improve its quality factor. The VCO is simulated at three typical TSMC fabrication comers (TT, FF, SS) to predict its measure results. The post simulation results shows that the VCO achieves a 20-25.5 GHz continuous tuning range. Its phase noise results at 1 MHz offset are -108.4 dBc/Hz and -100.5 dBc/Hz respectively at the tuning frequencies of 19.6 GHz and 25.5 GHz. The VCO draws only 3 to 6 mA from a 1.2 V power supply. 相似文献
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瑞利衰落信道Jakes模型的研究与性能分析 总被引:1,自引:0,他引:1
无线衰落信道是无线通信系统的重要组成部分,因此信道建模和仿真对于无线通信系统的开发具有极其重要的作用。文章通过对平坦瑞利(Rayleigh)衰落信道进行仿真建模研究,给出了瑞利衰落信道可以采用Jakes模型进行建模的分析结果。 相似文献
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介绍适用于衰落信道的Clarke模型的频谱分析,并导出一种计算机模拟Clarke模型的方法。针对FSK调制,利用MATLAB函数对该模型进行了仿真研究,得出了误码率曲线和时域波形,结果表明所建的模型是合理的,这为分析衰落信道的特性提供了一种分析方法。 相似文献
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无线通信系统信道模型研究 总被引:1,自引:1,他引:1
随着通信技术的发展,对无线信道的建模研究也随之经历了不同的阶段。本文研究了在每个发展阶段出现的信道模型,并且详细研究了几种主要且常见的信道模型的特点和性能,对比了几种模型的适用范围,为在实际应用中选择合适的信道模型提供了一定的理论参考依据。 相似文献
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Seok‐Bong Hyun Geum‐Young Tak Sun‐Hee Kim Byung‐Jo Kim Jinho Ko Seong‐Su Park 《ETRI Journal》2004,26(3):229-240
This paper reports on our development of a dual‐mode transceiver for a CMOS high‐rate Bluetooth system‐on‐chip solution. The transceiver includes most of the radio building blocks such as an active complex filter, a Gaussian frequency shift keying (GFSK) demodulator, a variable gain amplifier (VGA), a dc offset cancellation circuit, a quadrature local oscillator (LO) generator, and an RF front‐end. It is designed for both the normal‐rate Bluetooth with an instantaneous bit rate of 1 Mb/s and the high‐rate Bluetooth of up to 12 Mb/s. The receiver employs a dualconversion combined with a baseband dual‐path architecture for resolving many problems such as flicker noise, dc offset, and power consumption of the dual‐mode system. The transceiver requires none of the external image‐rejection and intermediate frequency (IF) channel filters by using an LO of 1.6 GHz and the fifth order on‐chip filters. The chip is fabricated on a 6.5‐mm2 die using a standard 0.25‐μm CMOS technology. Experimental results show an in‐band image‐rejection ratio of 40 dB, an IIP3 of ?5 dBm, and a sensitivity of ?77 dBm for the Bluetooth mode when the losses from the external components are compensated. It consumes 42 mA in receive π/4‐diffrential quadrature phase‐shift keying (π/4‐DQPSK) mode of 8 Mb/s, 35 mA in receive GFSK mode of 1 Mb/s, and 32 mA in transmit mode from a 2.5‐V supply. These results indicate that the architecture and circuits are adaptable to the implementation of a low‐cost, multi‐mode, high‐speed wireless personal area network. 相似文献
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提出了一个新的解析的适用于SOI MOSFET's的高频噪声模型.该模型通过耦合能量平衡方程克服了以往噪声模型所具有的缺点,并对短沟SOI器件的噪声给出精确地描述.同时,利用该模型可以容易地计算出相对于最小噪声值处的优化的栅源电压,为低噪声的电路设计提供优化的设计方向.由于该噪声模型的简单性,可以很方便地将模型植入电路模拟器如SPICE中完成电路设计. 相似文献
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A mathematical model that predicts the dynamic flows in cellular mobile networks that allocate channels using the Borrowing Channel Assignment (BCA) scheme is described in this paper. Two types of handoff procedures – the prioritized and non-prioritized schemes – will be considered in the model. Discrete event simulations were performed and the results were found to be comparable to the results obtained using the mathematical model. Application to comparative study of the dynamic behaviours of the BCA and the Fixed Channel Assignment (FCA) schemes is also presented. 相似文献