Multiple interferences suppression with space-polarization null-decoupling for polarimetric array

The adaptive digital beamforming technique in the space-polarization domain suppresses the interference with forming the coupling nulls of space and polarization domain.When there is the interference in mainlobe,it will cause serious mainlobe distortion,that the target detection suffers from.To overcome this problem and make radar cope with the complex multiple interferences scenarios,we propose a multiple mainlobe and/or sidelobe interferences suppression method for dual polarization array radar.Specifically,the proposed method consists of a signal preprocessing based on the proposed angle estimation with degree of polarization(DoP),and a filtering criterion based on the proposed linear constraint.The signal preprocessing provides the accurate estimated parameters of the interference,which contributes to the criterion for null-decoupling in the space-polarization domain of mainlobe.The proposed method can reduce the mainlobe distortion in the space-polarization domain while suppressing the multiple mainlobe and/or sidelobe interferences.The effectiveness of the proposed method is verified by simulations.

Evaluation of polarization field in InGaN/GaN multiple quantum well structures by using electroluminescence spectra shift

In order to investigate the inherent polarization intensity in InGaN/GaN multiple quantum well(MQW) structures,the electroluminescence(EL) spectra of three samples with different GaN barrier thicknesses of 21.3 nm, 11.4 nm, and 6.5 nm are experimentally studied. All of the EL spectra present a similar blue-shift under the low-level current injection,and then turns to a red-shift tendency when the current increases to a specific value, which is defined as the turning point.The value of this turning point differs from one another for the three InGaN/GaN MQW samples. Sample A, which has the GaN barrier thickness of 21.3 nm, shows the highest current injection level at the turning point as well as the largest value of blue-shift. It indicates that sample A has the maximum intensity of the polarization field. The red-shift of the EL spectra results from the vertical electron leakage in InGaN/GaN MQWs and the corresponding self-heating effect under the high-level current injection. As a result, it is an effective approach to evaluate the polarization field in the InGaN/GaN MQW structures by using the injection current level at the turning point and the blue-shift of the EL spectra profiles.

SIMULTANEOUS MULTIPLE TARGET RECOGNITION USING POLARIZATION AGILE WAVES

A novel matching method for simultaneous multi-target recognition is proposed by jointly considering target's prior scattering knowledge and the polarization parameters of radar echoes. The matching coefficients are calculated for the judgment. MATLAB simulations show that several targets can be accurately recognized simultaneously, and a high recognition probability can be achieved in Monte Carlo simulations. The total execution time can be remarkably reduced in the Field Programmable Gate Array (FPGA) implementation of the matching procedure.

Secure Transmission in Downlink Non-Orthogonal Multiple Access Based on Polar Codes

Non-orthogonal multiple access(NOMA)is deemed to have a superior spectral efficiency and polar codes have became the channel coding scheme for control channel of enhanced mobile broadband(eMBB)in the fifth generation(5G)communication systems.In this paper,NOMA combined with polar codes is used to achieve secure transmission.Both degraded wiretap channel and non-degraded wiretap channel are considered,where an eavesdropper intercepts the communication between base station(BS)and users.For the degraded wiretap channel scenario,a secure polar encoding scheme is proposed in NOMA systems with power allocation to achieve the maximum secrecy capacity.With regard to the nondegraded wiretap channel,a polar encoding scheme with multiple-input-single-output(MISO)system is proposed,where artificial noise is generated at BS to confuse the eavesdropper’s channel via transmit beamforming.The security and the secure rate are employed respectively in order to measure the secrecy performance.We prove that the proposed schemes for each scenario can achieve the secure rate and can transmit the signal securely and reliably.The simulation results show that the eavesdropper hardly decoding the secure signal when the legitimate receiver can decode the signal with very low block error rate(BLER).

Practical Polar Code Construction For Degraded Multiple-Relay Networks

In this paper, based on the characteristics of polar codes, a new decode-and-forward strategy called generalized partial information relaying protocol is proposed for degraded multiple-relay networks with orthogonal receiver components(MRNORCs). In such a protocol, with the help of partial information from previous nodes, each relay node tries to recover the received source message and re-encodes part of the decoded message for transmission to satisfy the decoding requirements for the following relay node or the destination node. In order to construct practical polar codes, the nested structures are developed based on this protocol and the information sets corresponding to the partial messages forwarded are also calculated. The proposed scheme is proved to be capable of achieving the theoretical capacity of the degraded MRN-ORCs while still retains the low-complexity feature of polar codes. We perform simulations to testify the practicability of the proposed scheme and compare polar codes by using successive-cancellation list decoder(SCLD) with traditional low-density parity-check(LDPC) codes. The results show that the obtained polar codes provide significant gain.

Creation of Multiple Subwavelength Focal Spot Segments Using Phase Modulated Radially Polarized Multi Gaussian Beam

Based on the vector diffraction theory, the effect of complex phase filters on intensity distribution of a radially polarized multi Gaussian beam in the focal region of high NA lens is theoretically investigated. It is observed that a properly designed multi belt complex phase filter can generate subwavelength novel focal patterns including splitting of focal spots and generation of multiple focal spot segments such as eight, six and four focal spots along the optical axis are obtained. We expect that such an investigation is useful for optical manipulation and material processing, multiple high refractive index particle trapping technologies.

Designs of All-Optical Higher-Order Signed-Digit Adders Using Polarization-Encoded Based Terahertz-Optical-Asymmetric-Demultiplexer (TOAD)

Various designed circuits for multiple-valued all-optical arithmetic are demonstrated. The terahertz-optical-asymmetric-demultiplexer (TOAD) switch is used as the basic structure unit in the proposed circuits due to its compact size, thermal stability, and low power operation. The designs of trinary and quaternary signed-digit numbers based adders are presented using different polarized states of light. These proposed polarization-encoded based adders use much less switches and their speeds are higher than the intensity-encoded counterparts. Further, it will be shown that one of the proposed trinary signed-digit adders is twice as fast as a recently reported modified signed-digit adder.

SOME PROPERTIES OF MULTIPLE TAYLOR SERIES AND RANDOM TAYLOR SERIES

Some polar coordinates are used to determine the domain and the ball of convergence of a multiple Taylor series. In this domain and in this ball the series converges, converges absolutely and converges uniformly on any compact set properties of the series may also be studied. For some random multiple are some corresponding properties. Growth and other Taylor series there

Chiral multiple-resonance thermally activated delayed fluorescence materials based on chiral spiro-axis skeleton for efficient circularly polarized electroluminescence

Chiral luminescence materials have potential applications in the field of three-dimensional displays due to their circularly polarized luminescence(CPL)characteristics.However,the further development of circularly polarized organic light-emitting diodes(CP-OLEDs)needs to meet the requirements of high efficiency,high color purity,low cost,and high dissymmetry factor(gPLor gEL),chiral multiple resonance thermally activated delayed fluorescence(MR-TADF)materials are considered as candidates in these aspects.Herein,based on a pair of chiral spirofluorene precursors,two pairs of high-performance chiral MR-TADF emitters((R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB)are developed,which exhibit strong emissions peaking at 491 and 502 nm in toluene with full-width at half-maximum values of 25 and 33 nm,respectively.In addition,small singlet–triplet energy gaps of 0.15 and 0.10 eV with high absolute photoluminescence efficiencies of 95.0%and 96.7%are observed for p-Spiro-DtBuCzB and m-Spiro-DtBuCzB molecules,respectively.OLEDs based on p-Spiro-DtBuCzB and m-Spiro-DtBuCzB display high maximum external quantum efficiencies of 29.6%and 33.8%,respectively.Most importantly,CP-OLEDs present symmetric circularly polarized electroluminescence spectra with|gEL|factors of 3.36×10^(-4)and 7.66×10^(-4)for devices based on(R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB enantiomers,respectively.

固体核磁共振Multiple-CP定量技术的参数优化与应用研究

固体核磁共振Multiple-CP定量技术可实现对不同体系、不同定量信息的检测.然而,Multiple-CP对样品属性的宽容度较低,其中有关样品属性的核磁共振参数包括氢的自旋晶格弛豫时间(T1,H)、交叉弛豫时间(T_(CH))和自旋锁定场下氢的自旋晶格弛豫时间(T^(H)_(1)ρ)等.因而需要系统地掌握Multiple-CP各种实验参数与样品上述特性参数之间的关系,从而确定Multiple-CP技术可适用的体系范围以及最优的实验参数范围.基于此,首先以L-丙氨酸为模型样品,探讨在Multiple-CP实验中弛豫恢复时间(t_(d))、交叉极化接触时间(t_(p))和交叉极化次数(n)3种实验参数对分子中基团比例测量结果的影响规律.并以L-缬氨酸、L-丙氨酸/L-缬氨酸的混合物为模型样品,探讨样品特性参数的差异性对Multiple-CP实验参数范围的影响.实验结果表明,t_(p)受T_(CH)和T^(H)_(1)的影响较大.对于纯净物或均相体系,T_(CH)是影响t_(p)参数设置的关键.依据实验数据发现,当样品中各基团T_(CH)差异度小于8%时,实验对t_(p)的宽容度较高;对于混合物体系,需同时考虑混合物中组分T^(H)_(1)差异度的影响.当组分T^(H)_(1)差异度为32%、各基团T_(CH)差异度为21%时,Multiple-CP对t_(p)的宽容度高,可在较宽的参数范围内实现定量检测.而当T_(CH)差异度较大时,获取定量结果时t_(p)的参数范围较小,实验条件较苛刻.Multiple-CP定量方法更适用于T_(CH)和T^(H)_(1)ρ差异度较小的样品体系的定量研究.通过研究样品T_(CH)和T^(H)_(1)对实验参数的影响,总结了Multi⁃ple-CP方法所适用的样品体系特征,为使用Multiple-CP进行定量检测提供可参考的参数设置方案.

多发性骨髓瘤细胞通过PI3K/AKT信号通路促进M2巨噬细胞极化的机制研究

背景多发性骨髓瘤发病率长期居高不下,但目前关于磷脂酰肌醇-3-激酶(PI3K)/丝氨酸/苏氨酸激酶(AKT)信号通路和M2巨噬细胞极化促进多发性骨髓瘤发生进展的研究较少。目的探讨M2巨噬细胞在多发性骨髓瘤患者中的表达及PI3K/AKT信号通路促进M2巨噬细胞极化的机制研究。方法选取2021年10月—2022年4月于桂林医学院附属医院血液内科确诊的多发性骨髓瘤患者48例为试验组,选取同期健康志愿者(血液内科骨髓移植健康供者)30名为对照组。取2组研究对象外周血并分离单个核细胞,流式细胞术检测M2巨噬细胞比例。采用细胞传代培养RPMI8226细胞,通过佛波酯分化培养单核巨噬细胞THP-1为巨噬细胞。根据实验需要将瘤细胞培养并采用siRNA转染沉默磷酸酶基因(PTEN)分成3组:空白组、siRNA-PTEN实验组、siRNA对照组;收集以上3组细胞培养基上清液加入巨噬细胞共培养体系后分为4组:M0巨噬细胞组、瘤细胞上清液组、siRNA-PTEN上清液组、siRNA上清液组。采用Western blot实验检测多发性骨髓瘤细胞培养的空白组、siRNA-PTEN实验组、siRNA对照组的AKT、p-AKT、PI3K-p85、p-PI3K-p85蛋白表达水平。采用荧光定量聚合酶链式反应(PCR)检测多发性骨髓瘤细胞培养的空白组、siRNA-PTEN实验组、siRNA对照组的基质金属蛋白酶(MMP)2、MMP9的mRNA表达水平。采用流式细胞术检测多发性骨髓瘤上清液共培养的M0巨噬细胞组、瘤细胞上清液组、siRNA-PTEN上清液组、siRNA上清液组M2巨噬细胞中特异性抗体CD163、CD206、F4/80表达水平。采用荧光定量PCR检测多发性骨髓瘤上清液共培养的M0巨噬细胞组、瘤细胞上清液组、siRNA-PTEN上清液组、siRNA上清液组M2巨噬细胞特异标志物精氨酸酶1(ARG-1)、白介素10(IL-10)的mRNA表达水平。结果试验组M2巨噬细胞表达水平高于对照组(t=0.855,P<0.001)。siRNA-PTEN实验组中p-AKT/AKT、p-PI3K-p85/PI3K-p85蛋白表达水平均高于空白组和siRNA对照组(P<0.05)。siRNA-PTEN实验组中MMP2、MMP9的mRNA表达水平均高于空白组和siRNA对照组(P<0.05)。siRNA-PTEN上清液组M2巨噬细胞特异性抗体CD163+F4/80、CD206+F4/80表达水平高于瘤细胞上清液组和siRNA上清液组(P<0.05)。siRNA-PTEN上清液组M2巨噬细胞特异标志物ARG-1、IL-10的mRNA表达水平高于瘤细胞上清液组和siRNA上清液组(P<0.05)。结论多发性骨髓瘤患者中M2巨噬细胞表达上调,多发性骨髓瘤细胞可通过激活PI3K/AKT信号通路促进M2巨噬细胞极化,调控骨髓瘤细胞微环境。

面向6G移动通信的极化多址接入技术

极化码是第一种达到信道容量的编码方案,是5G信道编码方案之一。面对6G更高可靠度、更低时延、更大连接的业务需求,提出面向6G的极化多址接入技术。极化多址接入技术能够充分利用多用户之间的极化效应,以实现更高的系统容量和系统接入能力。有源极化编码接入方案能够满足6G大容量高可靠的传输需求,无源极化编码随机接入方案能够提高系统的接入能力。这些方案表明,极化多址接入技术能够满足6G移动通信系统的超高可靠、高频谱效率、大容量的传输需求,是重要的候选技术之一。

Color-tunable circularly polarized electroluminescence from a helical chiral multiple resonance emitter with B–N bonds

Chiral B,N-doped polycyclic aromatic hydrocarbons with circularly polarized luminescence(CPL) and small full-width at halfmaxima(FWHM) are promising multiple resonance(MR) emitters for CP organic light-emitting diodes(CP-OLEDs).This work presents a pair of chiral MR enantiomers,P/M-o[B-N]_(2)N_(2),featuring B–N bonds incorporated within a[7]-helicene skeleton.These enantiomers exhibit narrow 0-0 and 0-1 electronic transition bands,whose relative intensity can be fine-tuned by increasing doping concentrations,resulting in redshifts of the emission peak from 542 to 592 nm.The enantiomers show mirrorsymmetric CPL spectra with an asymmetry factor(|g_(PL)|) of 1.0×10^(-3).The hyperfluorescent CP-OLEDs with double-sensitized emitting layers display a FWHM of 33 nm,an external quantum efficiency of 25.1%,and a|g_(EL)|factor of 7.7×10^(-4).Notably,the CP-OLEDs realize color-tunable CP electroluminescence peak from 553 to 613 nm by regulating the vibrational coupling.This work provides a novel concept for the design of helical CP-MR materials and CP-OLEDs,highlighting their potential for future applications in advanced optoelectronic devices.

西藏德新铅多金属矿床地球物理与地球化学综合找矿研究

德新铅多金属矿床是冈底斯多金属成矿带西段受构造—岩浆控制的中—低温热液型多金属矿床之一。通过对岩(矿)石电阻率、极化率及主微量元素等物性参数和地球化学特征进行分析,综合解释矿区矿致异常,并利用多元统计分析方法对成矿元素进行研究。结果表明:德新铅多金属矿床矿体的极化率及电阻率与围岩存在明显差异,可划分为低阻高极化和高阻高极化2种类型,对应8处激电异常,推测JD3-5和JD4低阻高极化异常为矿致异常,具有深部找矿潜力,是区内找矿勘查的重点区域之一;Pb、Zn、Cu、Mo、Ni和In等元素相关性显著,是德新铅多金属矿床的主要成矿元素;成矿过程前期主要受中—高温岩浆热液矿化类型Zn-Mo-Pb和Cu-Ni-In的影响,后期主要受含有Sc-Cr-Li和Hf-Be元素的流体及围岩的影响,其中Pb元素受Ni、Mo和In影响强烈,Zn元素受Mo的影响强烈。上述认识能够为找矿预测提供有用的宏观及微观信息,对该区域综合找矿具有重要的指导意义。

Broadband perfect polarization conversion metasurfaces

We propose a broadband perfect polarization conversion metasurface composed of copper sheet-backed asymmetric double spilt ring resonator（DSRR）. The broadband perfect polarization convertibility results from metallic ground and multiple plasmon resonances of the DSRR. Physics of plasmon resonances are governed by the electric and magnetic resonances. Both the simulation and measured results show that the polarization conversion ratio（PCR） is higher than 99%for both x- and y-polarized normally incident EM waves and the fractional bandwidth is about 34.5%. The metasurface possesses the merits of high PCR and broad bandwidth, and thus has great application values in novel polarization-control devices.

FURTHER APPLICATIONS OF POLAR COORDINATES IN C^n

Simplify the proof on the domain of convergence of multiple power series and consider the case where some of z1, …, zn are contained only in a finite number of terms of the series. Obtain some results on holomorphic functions in Cn.

Statistical Modeling of the High Altitude Platform Dual-Polarized MIMO Propagation Channel

In order to investigate the benefit of multiple-input multiple-output(MIMO) technique applying to the high altitude platform(HAP), a 2×2 MIMO statistical model, which can accurately describe the channel between HAP and high-speed train, is presented. And dual polarization diversity is particularly considered. Based on first-order three-state Markov chain, the single-input single-output(SISO) channel, a subset of the MIMO channel is first established. The ray tracing approach applied to the digital relief model(DRM) which covers the railway between Xi'an and Zhengzhou is used to obtain the state probability vector and matrix of the state transition probability. The proposed model considers both Doppler shift and temporal correlation, and the polarization correlation and spatial correlation statistical properties of large-scale fading and smallscale fading are analyzed. Moreover, useful numerical results on the MIMO HAP channel outage capacity are provided based on which, significant capacity gains with respect to the conventional SISO case are illustrated. Such statistical channel model can be applied to the future wireless communication system between HAP and high-speed train.

Polar码在保密通信中的应用研究

Polar码是一种能够达到香农限且编译码复杂度低的基于信道极化理论的信道编码方法。本文简单介绍了极化码在窃听信道中的构造方法。同时为非退化窃听模型,提出利用多次反馈来扩大等效主信道和窃听信道之间的差距,通过反馈实现非退化向退化的等效转变。仿真结果表明在二进制对称窃听信道下,所提出的基于多次反馈的传输方案误码率性能明显优于一次反馈,保证了信息可以更好地进行安全可靠地传输。

Joint DOA and polarization estimation for unequal power sources based on reconstructed noise subspace

In most literature about joint direction of arrival（DOA） and polarization estimation, the case that sources possess different power levels is seldom discussed. However, this case exists widely in practical applications, especially in passive radar systems. In this paper, we propose a joint DOA and polarization estimation method for unequal power sources based on the reconstructed noise subspace. The invariance property of noise subspace（IPNS） to power of sources has been proved an effective method to estimate DOA of unequal power sources. We develop the IPNS method for joint DOA and polarization estimation based on a dual polarized array. Moreover, we propose an improved IPNS method based on the reconstructed noise subspace, which has higher resolution probability than the IPNS method. It is theoretically proved that the IPNS to power of sources is still valid when the eigenvalues of the noise subspace are changed artificially. Simulation results show that the resolution probability of the proposed method is enhanced compared with the methods based on the IPNS and the polarimetric multiple signal classification（MUSIC） method. Meanwhile, the proposed method has approximately the same estimation accuracy as the IPNS method for the weak source.

Impact of Depolarization Phenomena on Polarized MIMO Channel Performances

The performance and capacity of multiple-input multiple-output (MIMO) wireless channels are limited by the spatial fading correlation between antenna elements. This limitation is due to the use of mono polarized antennas at receiver and transmitter sides. In this paper, in order to reduce the antenna correlation, the polarization diversity technique is employed. Although the spatial antenna correlation is attenuated for multi-polarization configurations, the cross-polar components appear. This paper highlights the impact of depolarization effect on the MIMO channel capacity for a 4&amp;amp;amp;#215;4 uniform linear antenna array. We assume that the channel is unknown at the transmitter and perfectly known at the receiver so that equal power is distributed to each of the transmit antennas. The numerical results illustrate that for low depolarization and spatial correlation, the capacity of single-polarization configuration behaves better than that of multi-polarization configuration.