- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 24th Microoptics Conference (MOC) - Toyama, Japan (2019.11.17-2019.11.20)] 2019 24th Microoptics Conference (MOC) - Patterned emission of organic light emitting diodes with laser irradiation
摘要： Self-healing networks aim to detect cells with service degradation, identify the fault cause of their problem, and execute compensation and repair actions. The development of this type of automatic system presents several challenges to be confronted. The first challenge is the scarce number of historically reported faults, which greatly complicates the evaluation of novel self-healing techniques. For this reason, in this paper, a system model to simulate faults in Long-Term Evolution (LTE) networks, along with their most significant key performance indicators, is proposed. Second, the expert knowledge required to build a self-healing system is usually not documented. Therefore, in this paper, a methodology to extract this information from a collection of reported cases is proposed. Finally, following the proposed methodology, an automatic fuzzy-logic-based system for fault identification in LTE networks is designed. Evaluation results show that the fuzzy system provides fault identification with a high success rate.
关键词： Long-Term Evolution (LTE),Diagnosis,fuzzy logic,fault identification,troubleshooting,root cause analysis,self-healing,fault management
更新于2025-09-23 15:21:01
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A Scalable Soft-Switching Photovoltaic Inverter with Full-Range ZVS and Galvanic Isolation
摘要： The introduction of heterogeneous wireless mesh technologies provides an opportunity for higher network capacity, wider coverage, and higher quality of service (QoS). Each wireless device utilizes different standards, data formats, protocols, and access technologies. However, the diversity and complexity of such technologies create challenges for traditional control and management systems. This paper proposes a heterogeneous metropolitan area network architecture that combines an IEEE 802.11 wireless mesh network (WMN) with a long-term evolution (LTE) network. In addition, a new heterogeneous routing protocol and a routing algorithm based on reinforcement learning called cognitive heterogeneous routing are proposed to select the appropriate transmission technology based on parameters from each network. The proposed heterogeneous network overcomes the problems of sending packets over long paths, island nodes, and interference in WMNs and increases the overall capacity of the combined network by utilizing unlicensed frequency bands instead of buying more license frequency bands for LTE. The work is validated through extensive simulations that indicate that the proposed heterogeneous WMN outperforms the LTE and Wi-Fi networks when used individually. The simulation results show that the proposed network achieves an increase of up to 200% in throughput compared with Wi-Fi-only networks or LTE-only networks.
关键词： routing protocol,long-term evolution (LTE),reinforcement learning,next-generation network,Heterogeneous networks,wireless mesh network (WMN)
更新于2025-09-23 15:21:01
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Wideband Hybrid Envelope Tracking Modulator With Hysteretic-Controlled Three-Level Switching Converter and Slew-Rate Enhanced Linear Amplifier
摘要： A wideband hybrid Envelope tracking (ET) modulator utilizing a hysteretic-controlled three-level switching converter (3L-SWC) and a slew-rate enhanced linear ampli?er (LA) are presented. In addition to smaller ripple and lower losses of 3L-SWCs, employing the proposed hysteresis control results in a higher speed loop and wider bandwidth converter, enabling over 80 MHz of switching frequency. A concurrent sensor circuit monitors and regulates the ?ying capacitor voltage VCF and eliminates the conventionally required calibration loop to control it. The hysteretic-controlled 3L-SWC provides a high percentage of power ampli?er (PA) supply load current with lower ripple, reducing the LA high-frequency current and ripple cancellation current, improving the overall system ef?ciency. A slew-rate enhancement (SRE) circuit is employed in the LA, resulting in slew rate of over 307 V/μs and bandwidth of over 275 MHz for the LA. The SRE circuit provides a parallel auxiliary current path directly to the gate of the class-AB output stage transistors, speeding-up the charging or discharging of output without modifying the operating point of the remaining LA, while maintaining the quiescent current of the class-AB stage. The supply modulator is fabricated in a 65-nm CMOS process. The measurement results show the tracking of long-term evolution (LTE)-40-MHz envelope with 93% peak ef?ciency at 1-W output power, while the SRE is disabled. Enabling the SRE, it can track LTE-80-MHz envelope with peak ef?ciency of 91%.
关键词： long-term evolution (LTE),LTE-advanced,hysteresis control,Envelope tracking (ET),supply modulator,power ampli?er (PA),three-level switching converter (3L-SWC),slew-rate enhancement (SRE),hybrid
更新于2025-09-19 17:13:59
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[IEEE 2018 International Conference on Applied Electromagnetics, Signal Processing and Communication (AESPC) - Bhubaneswar, India (2018.10.22-2018.10.24)] 2018 International Conference on Applied Electromagnetics, Signal Processing and Communication (AESPC) - Temperature effect on a-SiCN:H waveguide for application of sensing
摘要： Long term evolution-wireless local area network (LTE-WLAN) aggregation (LWA) has recently emerged as a promising third generation partnership project (3GPP) Release 13 technology to efficiently aggregate LTE and WLAN at the packet data convergence protocol layer, allowing uplink traffic to be carried on LTE and downlink on both LTE and WLAN. This removes all the contention asymmetry problems of WLAN and allows an optimum usage of both licensed and unlicensed band for downlink. In this paper, we present a new feature of LWA, its flow control scheme, which controls how to aggregate downlink traffic in licensed and unlicensed bands. This aggregation technique exploits user equipment-based flow control feedback in the form of LWA status reports, and can be expanded to work with any number of frequency bands and radio technologies. The same concepts apply to 5G networks, although the performance evaluation provided here is in the context of LTE-Advanced Pro. Simulation results in a typical enterprise scenario show that LWA can enhance user performance up to 8 times over LTE-only, and 3.7 times over WLAN only networks, respectively. The impact of the file size and LWA status report frequency on network performance is also investigated.
关键词： wireless local area network (WLAN),aggregation,LTE WLAN aggregation (LWA),flow control,long term evolution (LTE),Cellular networks
更新于2025-09-19 17:13:59
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[IEEE 2019 Compound Semiconductor Week (CSW) - Nara, Japan (2019.5.19-2019.5.23)] 2019 Compound Semiconductor Week (CSW) - Electron selective contact for high efficiency core-shell nanowire solar cell
摘要： Self-healing networks aim to detect cells with service degradation, identify the fault cause of their problem, and execute compensation and repair actions. The development of this type of automatic system presents several challenges to be confronted. The first challenge is the scarce number of historically reported faults, which greatly complicates the evaluation of novel self-healing techniques. For this reason, in this paper, a system model to simulate faults in Long-Term Evolution (LTE) networks, along with their most significant key performance indicators, is proposed. Second, the expert knowledge required to build a self-healing system is usually not documented. Therefore, in this paper, a methodology to extract this information from a collection of reported cases is proposed. Finally, following the proposed methodology, an automatic fuzzy-logic-based system for fault identification in LTE networks is designed. Evaluation results show that the fuzzy system provides fault identification with a high success rate.
关键词： Long-Term Evolution (LTE),Diagnosis,fuzzy logic,fault identification,troubleshooting,root cause analysis,self-healing,fault management
更新于2025-09-19 17:13:59
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Channel Estimation and Equalization for SS-OOFDM System with High Mobility
摘要： When orthogonal frequency division multiplexing (OFDM) is used in high-speed mobile scenarios, the traditional implementation of the OFDM receiver causes signi?cant performance degradation. This letter proposes a subband superposed oversampled OFDM (SS-OOFDM) scheme for accommodating the diverse scenarios, including the scenarios with high mobility. To track the fast-varying mobile channel, a time-domain channel estimation method is developed to ?rstly obtain the channel impulse response (CIR) values at pilots by means of the basis expansion model. Subsequently, by utilizing Slepian sequences-based interpolation, the CIR values at data symbols are reconstructed. Furthermore, we design a subband decision feedback and feedforward equalizer (SDFFE) for exploiting the Doppler and multipath diversity gains. Simulation results show that the SS-OOFDM, especially in high-speed mobile channels, outperforms the traditional OFDM receiver in terms of the bit-error-rate (BER) performance.
关键词： Mobile Channel,SS-OOFDM,OFDM,Channel Estimation and Equalization,Long Term Evolution (LTE)
更新于2025-09-10 09:29:36