- 标题
- 摘要
- 关键词
- 实验方案
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Efficient quantum state transmission via perfect quantum network coding
摘要： Quantum network coding with the assistance of auxiliary resources can achieve perfect transmission of the quantum state. This paper suggests a novel perfect network coding scheme to efficiently solve the quantum k-pair problem, in which only a few assisting resources are introduced. Specifically, only one pair of maximally entangled state needs to be pre-shared between two intermediate nodes, and only O(k) of classical information is transmitted though the network. Moreover, the classical communication used in our protocol does not cause transmission congestion, providing better adaptability to large-scale quantum k-pair networks. Through relevant analyses and comparisons, we demonstrate that our proposed scheme saves resources and has good application value, thereby showing its high efficiency. Furthermore, the proposed scheme achieves 1-max flow quantum communication, and the achievable rate region result is extended from its counterpart over the butterfly network.
关键词： achievable rate region,perfect quantum network coding,efficient quantum state transmission,communication efficiency,quantum k-pair problem
更新于2025-09-04 15:30:14
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Transmission Spectroscopy in Noninvasive Blood Glucose Measurement
摘要： The use of laser diodes and photodiodes in transmission spectroscopy has some effects (temperature, time, spectral, and spatial) reducing the accuracy of glucose measurement. These effects can be reduced by using a (1600 ± 3) nm laser in combination with fixation and occlusion of the tissue area under examination. In this work, a method is suggested that allows spatial displacements of the system to be taken into account. A number of methods for reducing the effect of the thermal drift of the diodes are also suggested. A portable noninvasive optical glucose meter implemented using these methods provides high clinical performance: more than 97% of the measurements are in the A and B zones of the Parkes error grid.
关键词： photodiodes,transmission spectroscopy,noninvasive blood glucose measurement,laser diodes,thermal drift,spatial displacements
更新于2025-09-04 15:30:14
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - A novel single layer dual linear polarization band-pass frequency selective surface for automotive fully coated glass
摘要： A single layer dual linear polarization Frequency Selective Surface (FSS) for automotive fully coated glass is presented. It acts as a band-pass ?lter for signals in the range of 640MHz to 3.3GHz. The performance of the proposed FSS element is assessed using CST Microwave Studio R(cid:2). Simulations show less than 10dB of attenuation all over the frequency band for an angle of incidence up to 70? in both polarizations. This promising result makes from the proposed FSS a good candidate to overcome the problem of connectivity of a handled device inside the vehicle to the mobile network.
关键词： transmission,Frequency Selective Surface,automotive application
更新于2025-09-04 15:30:14
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - Simplified Molecular Absorption Loss Model for 275-400 Gigahertz Frequency Band
摘要： This paper focuses on giving a simpli?ed molecular absorption loss model for a 275 – 400 GHz frequency band, which has signi?cant potential for variety of future short and medium range communications. The band offers large theoretical data rates with reasonable path loss to theoretically allow even up to kilometer long link distances when suf?ciently high gain antennas are used. The molecular absorption loss in the band requires a large number of parameters from spectroscopic databases, and, thus, the exact modeling of its propagation characteristics is demanding. In this paper, we provide a simple, yet accurate absorption model, which can be utilized to predict the absorption loss at the above frequency band. The model is valid at a regular atmospheric pressure, it depends on the distance, the relative humidity, and the frequency. The existing simpli?ed model by ITU does not cover frequencies above 350 GHz and has more complexity than our proposed model. The molecular absorption loss increases exponentially with the distance, decreasing the utilizable bandwidth in the vicinity of the absorption lines. We provide a model to approximate the window widths at the above frequency band. This model depends on the distance, the relative humidity, the frequency, and the maximum tolerable loss. It is shown to be very accurate below one kilometer link distances.
关键词： transmission window model,molecular absorption loss,275–400 GHz frequency band,simplified model
更新于2025-09-04 15:30:14
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - Thin Cavity-Backed Slot Antenna for Deeply Implantable Devices
摘要： Active implantable medical devices have tremendously improved the life quality and span of millions of people. Wireless power and/or information transfer between implanted and external devices bring huge benefits to patients, clinicians and researchers in terms of comfortability, mobility, implanted device performance optimisation, transferring critical physiological information for treatment, understanding desease, drug development and so on. In this context, implanted and wearable antennas are critical components for building a robust link between implanted and external devices. This paper reports on a thin cavity-backed slot wearable antenna that was designed for communication with a deeply implanted device. Apart from general requirement of antenna performance, the wearable antenna design places emphasis on ergonomics and user comfort. The fabricated thin and light weight circular cavity-backed slot antenna was assembled with a breathable foam and a flexible conductive sheet. The measured antenna bandwidth overlaps with implanted device operating frequency range. A computer model was used to estimate the path loss in tissue. The antenna was placed on the human model chest wall and the path loss to the target implantation site was calculated. The simulation results suggest that the path loss at an implantation depth of 6 cm from skin is about 25 dB.
关键词： wearable antenna,transmission characterisation,implantable device,cavity-back antenna
更新于2025-09-04 15:30:14
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Efficient Indoor Data Transmission with Full Dimming Control in Hybrid Visible Light / Infrared Communication Systems
摘要： We design a hybrid visible light (VL) and infrared (IR) data transmission scheme for indoor visible light communication (VLC) systems with multi-pulse position modulation (MPPM) dimming control. A low-power IR light-emitting diode (LED) is adopted to assist the VL downlink especially when the dimming level of VL is low. Both VL and IR orthogonal frequency division multiplexing (OFDM) signals are transmitted alternately during the “on” and “off” periods of MPPM dimming controlled pulses. In this way, MPPM “off” periods can be efficiently utilized to convey data information without affecting illumination level. This arrangement ensures reliable data transmission under all illumination conditions including dark scenario. Numerical results show that the additional IR link can always facilitate the use of low M-ary quadrature amplitude modulation (M-QAM) levels. The fluctuation of required M-QAM symbol rates caused by dimming control can also be mitigated. At low dimming levels, both the receiver sensitivity requirement for the VL link and the total required transmit power can be significantly alleviated while maintaining a constant data rate at BER < 10-3. Even with limited launching power, the proposed scheme can still extend dimming control range while achieving stable and reliable transmission quality effectively.
关键词： multi-pulse position modulation (MPPM),Visible light communication (VLC),infrared (IR) communication,dimming control,orthogonal frequency division multiplexing (OFDM),hybrid transmission
更新于2025-09-04 15:30:14
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[IEEE 2018 11th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP) - Budapest (2018.7.18-2018.7.20)] 2018 11th International Symposium on Communication Systems, Networks & Digital Signal Processing (CSNDSP) - Modeling and Throughput Analysis of FSO Systems using GBN-ARQ and AR Transmission over Atmospheric Turbulence Channels
摘要： This paper addresses the error-control issue in free-space optical (FSO) communications. In particular, we model and analyze the throughput performance of FSO systems over atmospheric fading channel when the go-back-N (GBN) automatic repeat request (ARQ) and adaptive rate (AR) transmission schemes are employed. For this purpose, we first build the model to capture the time-varying behavior in atmospheric fading channels. We then use that channel model to develop the burst error model for GBN-ARQ with AR in order to analytically derive the system throughput. Numerical results quantitatively show the impacts of atmospheric turbulence on the throughput and confirm the effectiveness of the GBN/ARQ. Monte Carlo simulations are also performed to validate the analytical results.
关键词： throughput performance,go-back-N (GBN) automatic repeat request (ARQ),atmospheric turbulence,adaptive rate (AR) transmission,Free-space optical (FSO) communications
更新于2025-09-04 15:30:14
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Design and Validation of Flexible Multilayer Frequency Selective Surface with Transmission Zeros
摘要： The design, analysis and validation of a flexible multilayer frequency selective surface (MFSS) with two transmission zeros at the upper side of the passband is presented. The multilayer FSS unit cell is composed of two metallic quasi-Jerusalem-cross patterns on the top and the bottom layers, a metallic slot coupling aperture on the middle layer, and two flexible polyimide-teflon supported substrates. The equivalent circuit is derived to explain the principle of transmission poles and zeros. This MFSS exhibits good resonance stability for different polarization and incident angles. A prototype flexible MFSS centered at 21.6 GHz is fabricated and measured, which shows an insertion loss of 1.3 dB and a fractional bandwidth of 15.7%. The stable performances of the MFSS at oblique incidences and under different bent conditions for TE and TM polarization are demonstrated as well.
关键词： flexible substrate,Multilayer frequency-selective surface (MFSS),transmission zeros
更新于2025-09-04 15:30:14
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Terahertz rectangular corrugated transmission line with Gaussian mode filtering for DNP-NMR
摘要： Gyrotrons have been developed as terahertz wave sources in dynamic nuclear polarisation (DNP) system to increase the sensitivity of nuclear magnetic resonance (NMR) in the high-magnetic field regime. However, the transmission of the Gaussian beam from the gyrotron output window to the NMR system proves to be a critical challenge. In this study, a terahertz transmission system, composed of a rectangular corrugated waveguide and a back-to-back rectangular corrugated horn for Gaussian mode filtering, is proposed. The attenuation in the optimised 0.33?THz corrugated waveguide remains lower than 0.01 dB/m in a broad frequency range from 280?GHz to 450?GHz. Besides, the coupling coefficient from the electric field in the 0.33 THz mode-filtering horn to the fundamental HE11 mode in the rectangular corrugated waveguide is obtained nearly 99.5%. This terahertz transmission system is potential to be applied in DNP-NMR spectrometer based on continuous wave gyrotrons.
关键词： DNP-NMR,Gaussian mode filtering,terahertz,transmission line,gyrotron
更新于2025-09-04 15:30:14
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A NOVEL DUAL-BAND SIW FILTER WITH HIGH SELECTIVITY
摘要： A novel dual-band substrate integrated waveguide (SIW) ?lter with multiple transmission zeros and good out-of-band rejection performance is presented in this paper. For this purpose, an orthogonal input/output (I/O) feeding structure directly connected to the substrate integrated waveguide (SIW) cavity is designed to split the resonant frequencies of the degenerate pair of mode. The ?lter can be modeled with a multi-path circuit formed by three modes (TE101, TE201 and TE102 modes) and weak cross coupling between I/O ports, thereby producing three transmission zeros which make the dual-band high selectivity. The o?set of the input/output ports shifts the second transmission zero to a lower frequency from the upper passband. Several ?lter prototypes are designed and fabricated for demonstration, and the measured results validate the new structure for high selectivity applications.
关键词： high selectivity,substrate integrated waveguide (SIW),dual-band,orthogonal input/output feeding structure,transmission zeros
更新于2025-09-04 15:30:14