A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal （1D PC） is comprised of alternate dielectric layer and vacuum layer. Two quantum wells （QWs） as defects can be constructed...A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal （1D PC） is comprised of alternate dielectric layer and vacuum layer. Two quantum wells （QWs） as defects can be constructed by sandwiching two plasma slabs symmetrically in the 1D PC, and a dual-narrowband pass-band filter is formed. The conventional finite- difference time-domain （FDTD） method and piecewise linear current density recursive convolution （PLCDRC）-FDTD method are applied to the dielectric and plasma, respectively. The simulation results illustrate that the dual-narrowband frequencies can be tuned by changing the plasma frequency. The pass band interval and the half-power bandwidths （-3-dB band widths） are related to the space interval between two QWs.展开更多
A new Kalman filtering algorithm based on estimation of spread spectrum signal before suppression of narrowband interference （NBI） in spread spectrum systems, using the dependence of autoregressive （AR） interferen...A new Kalman filtering algorithm based on estimation of spread spectrum signal before suppression of narrowband interference （NBI） in spread spectrum systems, using the dependence of autoregressive （AR） interference, is presented compared with performance of the ACM nonlinear filtering algorithm, simulation results show that the proposed algorithm has preferable performance, there is about 5 dB SNR improvement in average.展开更多
The development of wireless communication standards necessitates optimal filter design for the selection of appropriate bands of frequencies.In this work,a compact in size pair of parallel coupled symmetric stepped im...The development of wireless communication standards necessitates optimal filter design for the selection of appropriate bands of frequencies.In this work,a compact in size pair of parallel coupled symmetric stepped impedancebased resonator is designed with supporting to the WiMAX communication standards.The coupled resonator is tuned to allow the frequency band between 3.4 GHz and 3.8 GHz,which is centered at 3.6 GHz.A parasitic effect of capacitively coupled feed structure is used for exciting the two symmetrical stepped impedance resonators.The bandwidth and selectivity of the filter are enhanced with the change of characteristic impedances and controlling the coupling gap between resonators.This design offers single narrow sharp passband selectivity as well as multiple stopband harmonic suppression arising as a result of multiple transmission zeros.The designed filter operates with a fractional bandwidth(FBW)of 11.47%.The proposed single narrowband bandpass filter provides better suppression in either side of the tuned frequency(3.6 GHz)without degrading the passband performance.Also,this novel filter offers an insertion loss of about−0.08 dB and a return loss of greater than−30 dB in passband.This approach is useful for eliminating unwanted spurious harmonics responses that enter the desired response.The suggested bandpass filter has been simulated using Advanced Design System(ADS)tool,and the measurement has been made using a network analyzer,and the results are reported.展开更多
A compact narrowband non-degenerate dual-mode microstrip filter with square shape cuts is presented. The structure is developed by loading the conventional non-degenerate dual-mode resonator by open circuit stubs at t...A compact narrowband non-degenerate dual-mode microstrip filter with square shape cuts is presented. The structure is developed by loading the conventional non-degenerate dual-mode resonator by open circuit stubs at two opposite corners. The filter bandwidth is controlled by only decreasing the higher cutoff frequency of the conventional type. With Square shape cuts, return loss is improved. A 20% fractional bandwidth filter is designed and implemented on FR4 material with 4.4 dielectric constant and 1.6 mm thickness at center frequency of 1.5 GHz with passband of 1.3 GHz to 1.6 GHz. Analysis has been achieved using the IE3D simulator. Experimental results do agree with simulations.展开更多
This paper presents an experimental verification of ultra-wideband bandpass filter (BPF) for UWB applications and notch filter in order to suppress 5 GHz narrowband service when it coexists with UWB radio system. The ...This paper presents an experimental verification of ultra-wideband bandpass filter (BPF) for UWB applications and notch filter in order to suppress 5 GHz narrowband service when it coexists with UWB radio system. The BPF consists of a hexagonal shaped multiple mode resonator (MMR) with interdigital coupling at both sides. Notch filter is derived from BPF by introducing four embedded open stubs near by the MMR. The developed BPF has insertion loss of –2 dB and the minimum return loss about –35 dB, while for the notch filter they are –3 dB and –40 dB respectively. The group delay obtained for bandpass filter is below 0.2 ns and for notch filter, it is about 0.3 ns. With the above structural features the overall dimensions of the filter is 38 mm (length) × 3.2 mm (breadth) × 1.6 mm (height) and the percentage fractional bandwidth (FBW) of the proposed filter is about 120.48%.展开更多
In this paper, rejection of multiple narrowband interferers in a binary phase shift keying modulated orthogonal frequency division multiplexing (BPSK-OFDM) system is investigated. The BPSK-OFDM system in consideration...In this paper, rejection of multiple narrowband interferers in a binary phase shift keying modulated orthogonal frequency division multiplexing (BPSK-OFDM) system is investigated. The BPSK-OFDM system in consideration operates in an additive white Gaussian noise (AWGN) channel. A cascade complex coefficient adaptive infinite impulse response (IIR) notch filter with gradient-based algorithm is used to reject the interferers. Bit error ratio (BER) performance of the system is studied and a general closed-form expression is derived assuming negligible steady-state leakage NBI and by estimating the decision variable as Gaussian distributed based on Central Limit Theorem (CLT). Dependence of the BER performance on the notch bandwidth coefficient is demonstrated by the analysis. Extensive simulation results are included to substantiate accuracy of the analysis.展开更多
窄带物联网(NarrowBand Internet of Things,NB-IoT)是实现万物互联重要的通信技术,其为了扩大通信覆盖范围和提高可靠性而牺牲了时延等性能指标,且难以动态适应移动物联网设备.对此,本文提出了一种适用于移动设备的NB-IoT无线电资源配...窄带物联网(NarrowBand Internet of Things,NB-IoT)是实现万物互联重要的通信技术,其为了扩大通信覆盖范围和提高可靠性而牺牲了时延等性能指标,且难以动态适应移动物联网设备.对此,本文提出了一种适用于移动设备的NB-IoT无线电资源配置方案.该方案通过卡尔曼滤波对物联网设备的移动位置进行预测,建立数学模型对通信可靠性进行估计,开展了块误码率、时延、能耗等性能指标的量化分析,并提出了无线电资源配置的优化模型和方法.本文基于真实数据集开展了仿真实验,对该方案的有效性进行了验证,实验结果显示该方案能保证移动物联网设备与基站连接的同时降低时延.展开更多
基金supported by the Aviation Science Foundation(Key Project 20121852030)Jiangsu Provincial Natural Science Foundation,China(Grant No.BK2011727)the Open Research Program in Jiangsu Provincial Key Laboratory of Meteorological Observation and Information Processing,China(Grant No.KDXS1207)
文摘A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal （1D PC） is comprised of alternate dielectric layer and vacuum layer. Two quantum wells （QWs） as defects can be constructed by sandwiching two plasma slabs symmetrically in the 1D PC, and a dual-narrowband pass-band filter is formed. The conventional finite- difference time-domain （FDTD） method and piecewise linear current density recursive convolution （PLCDRC）-FDTD method are applied to the dielectric and plasma, respectively. The simulation results illustrate that the dual-narrowband frequencies can be tuned by changing the plasma frequency. The pass band interval and the half-power bandwidths （-3-dB band widths） are related to the space interval between two QWs.
基金Project supported by National Natural Science Foundation of Chi-na (Grant No .60172018)
文摘A new Kalman filtering algorithm based on estimation of spread spectrum signal before suppression of narrowband interference （NBI） in spread spectrum systems, using the dependence of autoregressive （AR） interference, is presented compared with performance of the ACM nonlinear filtering algorithm, simulation results show that the proposed algorithm has preferable performance, there is about 5 dB SNR improvement in average.
文摘The development of wireless communication standards necessitates optimal filter design for the selection of appropriate bands of frequencies.In this work,a compact in size pair of parallel coupled symmetric stepped impedancebased resonator is designed with supporting to the WiMAX communication standards.The coupled resonator is tuned to allow the frequency band between 3.4 GHz and 3.8 GHz,which is centered at 3.6 GHz.A parasitic effect of capacitively coupled feed structure is used for exciting the two symmetrical stepped impedance resonators.The bandwidth and selectivity of the filter are enhanced with the change of characteristic impedances and controlling the coupling gap between resonators.This design offers single narrow sharp passband selectivity as well as multiple stopband harmonic suppression arising as a result of multiple transmission zeros.The designed filter operates with a fractional bandwidth(FBW)of 11.47%.The proposed single narrowband bandpass filter provides better suppression in either side of the tuned frequency(3.6 GHz)without degrading the passband performance.Also,this novel filter offers an insertion loss of about−0.08 dB and a return loss of greater than−30 dB in passband.This approach is useful for eliminating unwanted spurious harmonics responses that enter the desired response.The suggested bandpass filter has been simulated using Advanced Design System(ADS)tool,and the measurement has been made using a network analyzer,and the results are reported.
文摘A compact narrowband non-degenerate dual-mode microstrip filter with square shape cuts is presented. The structure is developed by loading the conventional non-degenerate dual-mode resonator by open circuit stubs at two opposite corners. The filter bandwidth is controlled by only decreasing the higher cutoff frequency of the conventional type. With Square shape cuts, return loss is improved. A 20% fractional bandwidth filter is designed and implemented on FR4 material with 4.4 dielectric constant and 1.6 mm thickness at center frequency of 1.5 GHz with passband of 1.3 GHz to 1.6 GHz. Analysis has been achieved using the IE3D simulator. Experimental results do agree with simulations.
文摘This paper presents an experimental verification of ultra-wideband bandpass filter (BPF) for UWB applications and notch filter in order to suppress 5 GHz narrowband service when it coexists with UWB radio system. The BPF consists of a hexagonal shaped multiple mode resonator (MMR) with interdigital coupling at both sides. Notch filter is derived from BPF by introducing four embedded open stubs near by the MMR. The developed BPF has insertion loss of –2 dB and the minimum return loss about –35 dB, while for the notch filter they are –3 dB and –40 dB respectively. The group delay obtained for bandpass filter is below 0.2 ns and for notch filter, it is about 0.3 ns. With the above structural features the overall dimensions of the filter is 38 mm (length) × 3.2 mm (breadth) × 1.6 mm (height) and the percentage fractional bandwidth (FBW) of the proposed filter is about 120.48%.
文摘In this paper, rejection of multiple narrowband interferers in a binary phase shift keying modulated orthogonal frequency division multiplexing (BPSK-OFDM) system is investigated. The BPSK-OFDM system in consideration operates in an additive white Gaussian noise (AWGN) channel. A cascade complex coefficient adaptive infinite impulse response (IIR) notch filter with gradient-based algorithm is used to reject the interferers. Bit error ratio (BER) performance of the system is studied and a general closed-form expression is derived assuming negligible steady-state leakage NBI and by estimating the decision variable as Gaussian distributed based on Central Limit Theorem (CLT). Dependence of the BER performance on the notch bandwidth coefficient is demonstrated by the analysis. Extensive simulation results are included to substantiate accuracy of the analysis.
文摘窄带物联网(NarrowBand Internet of Things,NB-IoT)是实现万物互联重要的通信技术,其为了扩大通信覆盖范围和提高可靠性而牺牲了时延等性能指标,且难以动态适应移动物联网设备.对此,本文提出了一种适用于移动设备的NB-IoT无线电资源配置方案.该方案通过卡尔曼滤波对物联网设备的移动位置进行预测,建立数学模型对通信可靠性进行估计,开展了块误码率、时延、能耗等性能指标的量化分析,并提出了无线电资源配置的优化模型和方法.本文基于真实数据集开展了仿真实验,对该方案的有效性进行了验证,实验结果显示该方案能保证移动物联网设备与基站连接的同时降低时延.
