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SWIPT can effectively deal with the energy limitation problem of communication terminals, and IRS can assist in enhancing the efficiency of SWIPT. Therefore, to overcome the shortcoming of limited coverage of deploying a single IRS and further improve the time and spectrum resource utilization efficiency of SWIPT, this paper studied a double-IRS-assisted NOMA SWIPT system, where the beamforming vector of the transmitter, the phase shifts of each IRS, and the power splitting coefficients of the receivers were jointly optimized to maximize the minimum user rate. To solve the above non-convex optimization problem with highly coupled variables, this paper proposed an AO algorithm based on SDR and SCA techniques to solve it efficiently. The simulation results show that the double-IRS-assisted system can achieve a higher minimum rate than that of its single-IRS, which reveals the superiority of deploying double IRS, the effectiveness of the proposed algorithm, and the importance of jointly optimizing IRS phase shifts and power splitting coefficients in improving the user rate performance. [ABSTRACT FROM AUTHOR]

As the core component of the radiation source transmitter, the power amplifier has the characteristics of high non - linearity and strong memory, which makes it difficult to model the behavior of the power amplifier. In view of this problem, this study proposes a method for behavior modeling of power amplifiers based on Deep TCN. The neural nelwork model adopled by Lhis melhod is composed of mulliple multi - dimensional Lime series convoluLion blocks, and each Lime series convolulion block is composed of several causal dilalion convolulions used Lo increase Lhe receptive field of the network and residual structures used to improve the efficiency of gradient feedback. Through the parallel convolution operation, the model overcomes the disadvantages of traditional convolutional networks that cannot handle variable - length sequences, and improves the efficiency of behavioral modeling while preserving the memory effect of power amplifiers. The behavior modeling results of measured data show that compared with the existing Vollerra series and recurrenl neural nelwork modeling methods, Lhe proposed melhod can significantly improve Lhe accuracy of behavior modeling. Compared wilh the recurrent neural nelwork modeling melhod, the proposed method reduces the implementation time by an order of magnitude in tem1s of the efficiency of behavior modeling. [ABSTRACT FROM AUTHOR]

With the development of the Internet of Things (IoT) technology and the rapid deployment of open wireless access mobile networks (such as 5th Generation Wireless Networks [5G], New Radio [NR], Long Term Evolution [LTE], Wi-Fi, etc.), more and more devices result in multi-user interference (MUI) within the signal transmission range, and may even suffer attacks or interceptions from some malicious users. Therefore, while wireless communication brings convenience, the security of users’ private information is also facing a huge challenge. As a communication signal waveform sent from a transmitter has its unique radio frequency fingerprint (RF fingerprint), which can be used to identify and authorize the transmitter device. In this article, we investigate the RF fingerprint of waveforms sent from a Wi-Fi transmitter, and discuss how to reduce receiver influence on the RF fingerprint associated with a transmitter. In this work, we propose a receiver calibration method, and a weighted classifier combining decision algorithm to improve the RF fingerprint identification rate. We hope this research can be extended to a more complex electromagnetic environment like 5G networks. It is expected that the self-interference phenomenon between these 5G devices can be mitigated if RF fingerprint identification technology can be adopted. Additionally, the RF fingerprint technology can be helpful for the functions of unified management and cost-saving of telecommunication operators. [ABSTRACT FROM AUTHOR]

BACKGROUND: Inflammatory transmitters secreted from the synovium may be one of the important factors inducing the onset of knee osteoarthritis, and further exacerbate knee osteoarthritis. OBJECTIVE: To observe the effect of different concentrations of catalpol from the root of Rehmannia glutinosa on the expression of interleukin-1β, galectin 3 and S100A12 in the synovium of the knee joint in rats with early knee osteoarthritis, and to explore the mechanism of catalpol from the root of Rehmannia glutinosa in the treatment of early knee osteoarthritis. METHODS: The 14 of 48 adult male Wistar rats were randomly selected as a normal control group, and the remaining 34 rats were injected with 4% papain and 0.03 mol/L cysteine solution (0.2 mL) into the right knee joint cavity at 1, 4, 7 days after the initialization of the experiment to duplicate the model of early knee osteoarthritis. At 10 days after the initialization of the experiment, 4 rats in each group were randomly selected for histological observation using hematoxylin-eosin staining and validation of the model using Mankin and OARSI grading evaluation. After the model was successfully verified, the remaining 30 rats in the model group were randomly divided into model control group, low-dose group and high-dose group. At 2 days after successful modeling, each treatment group was infused with corresponding drugs at a dose of 0.2 mL/kg, and normal control group and model control group were infused with normal saline, once a day for 28 consecutive days. The synovium of the right knee joint was then taken from rats in each group, and the expression of interleukin-1β, galectin 3 and S100A12 in the rat synovium was detected by ELISA. RESULTS AND CONCLUSION: Mankin score and OARSI grading were significantly higher in the model control group than the normal control group (P < 0.05). The levels of S100A12, interleukin-1β and galectin 3 in the synovium were significantly higher in the model control group than the normal control group (P < 0.01). Compared with the model control group, the levels of S100A12, interleukin-1β and galectin 3 in the synovium was decreased somewhat in the low-dose group (P < 0.05), but significantly decreased in the high-dose group (P < 0.01). Therefore, catalpol from the root of Rehmannia glutinosa can delay the progression of knee osteoarthritis by reducing the level of inflammatory factors in the synovium. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) is a gaseous transmitter that has received mounting interest because of its therapeutic potentials in the treatment of inflammation, bacterial infection, cancer and so on. However, the clinical application of CO is remarkably hindered by the difficulty in precisely controlling CO concentrations and the targeted delivery of CO to pathological tissues. To circumvent these problems, CO-releasing molecules (CORMs) have been developed and widely used as the alternative of gaseous CO to explore the physiological functions of CO and develop novel therapeutic agents. Unfortunately, conventional CORMs suffered from insufficient stability, short half-life, and poor biodistribution in biological conditions. Intriguingly, the encapsulation of CORMs into polymeric nanoparticles or covalently installation of CORMs to polymeric matrices remarkably improves the stability of CORMs, prolongs the releasing time and optimizes the biodistributions. In this review, we summarize the recent achievements of CO-releasing macromolecules and highlight three approaches used for the fabrication of CO-releasing macromolecules. Also, we envision the potential applications of these macromolecular CO donors and suggest future directions in this field. We hope that more efforts would be devoted to this emerging field to advance the clinical trial of macromolecular CO donors. [ABSTRACT FROM AUTHOR]

In order to solve the problems that the positioning information of the ADS - B transmitter is mainly taken from GPS and the limited distance of the transmission link，the technology of ADS-B monitoring based on"BeiDou"is researched. After a in-depth study on the ADS-B message protocol and making the"BeiDou" communication as a supplementary transmission link to ADS-B，the airborne monitoring terminal system using the"BeiDou"positioning source is designed and the seamless navigation and surveillance technology is studied for aircrafts. RX1E electric general aircraft and the established monitoring center system are used to test and verify the ADS-B and"BeiDou"transmissions of airborne terminal. The results show that the data transmission links realize wide-area surveillance of low-altitude airspace navigable aircraft， and the flight situation information sent by the airborne terminal realize the monitoring center 's online situation awareness of lowaltitude aircraft. The research results provide a technical reference for serving the operational safety of China's general aviation aircraft and improving the informationization level of low altitude airspace management. [ABSTRACT FROM AUTHOR]

The conventional adaptive waveform design of orthogonal frequency division multiplexing/offset quadrature amplitude modulation(OFDM/OQAM) system are mainly for the channel model of non-exponential-type delay power spectrum and non-U-type Doppler power spectrum. However, waveform adaptive design results in different channel matching criterion coefficients due to different channel models in practice. Therefore, this paper discussed the characteristics of ground air channel model and extended Gaussian function and proposed a new OFDM/OQAM waveform adaptive algorithm based on the traditional SINR-adaptive waveform design. This algorithm introduced a matching coefficient β into the traditional waveform matching criterion, which established the relation between the time-frequency domain and the maximum multipath delay-Doppler frequency shift of the waveform. Combined with the traditional optimization function of SINR, it optimized the parameters of the pulse shaping filter and then fed back to the transmitter to adjust the filter banks at the transmitter and receiver. Simulation results show that, under the modulation of 4QAM and 16 QAM, the channel matching coefficient β has an improvement of 1. 0 d B or more in the system error performance. [ABSTRACT FROM AUTHOR]

Different with the passive wireless eavesdropping technique in traditional wireless communications, this paper studied proactive eavesdropping technology at the physical layer for legitimate eavesdropper to monitor the communication between suspicious users. It equipped consider a multiple-input single-output(MISO) system model where the suspicious transmitter and legitimate jammer with multi antennas, and equipped the suspicious receiver and legitimate eavesdropper with single antenna, if the channel gain of the suspicious communication link was stronger than that of the eavesdropping link, the legitimate jammer controled the communication rate of the suspicious users via jamming them, in order for the legitimate eavesdropper to correctly decode the eavesdropped information. Considering two cases that the jammer could or couldn’t interference on the legitimate eavesdropper, respectively, it designed the optimal interference signal and power control for the legitimate jammer to maximize the eavesdropping rate. Simulation results show that the proposed interference design method for the jammer in different application scenarios has better eavesdropping performance than the existing two benchmark methods. [ABSTRACT FROM AUTHOR]

Mine transient electromagnetic method has a low resistivity problem for using minor transmitter and receiver loops, which leads to data interpretation difficulties and decreases detection depth. Firstly, this paper studied the variation of secondary field with transmitter-receiver distance through numerical simulation and field test, and found that the simulant secondary field was almost unchanged with transmitter-receiver distance within 20 m while measured data decreases linearly in logarithm coordinate system. Theoretical analysis shows that the mutual induced electromotive force is the main component of measured data, which leads to low resistivity problem. Furthermore, the paper proposed a resistivity correction method based on the different properties of secondary field and mutual induced electromotive force. The method eliminates the mutual induced electromotive force by using two measured data with different transmitter-receiver distances. Finally, the proposed method was successfully used in a half-space field case and a whole-space field case to demonstrate its practical usefulness. [ABSTRACT FROM AUTHOR]

The existence of the channel state information (CSI) gave the communication system self-adaptation to the channel, and guaranteed the high-speed and high reliable communication for multiple-input multiple-output (MIMO) systems. It was often practical for the receivers to get the CSI, while it needed some condition for the CSI at transmitters (CSIT). Capacity was the most important measurement for the transmission capability of channel, and degree of freedom (DoF) was the main factor to represent the linear scalability of the capacity. As a result, the existence of CSIT would affect to the capacity and DoF of MIMO networks. This paper studied and compared the impact to the DoF and region of DoF of the MIMO networks by the CSIT in different constraints, including the broadcasting channel (BC), interference channel (IC), X channel (XC). Finally it concluded that CSIT could increase the DoF in the most scenarios for these networks. The region of DoF of MIMO XC with CSIT, the DoF and region of DoF of multi networks coexistence need further research. [ABSTRACT FROM AUTHOR]

The use of wavelength division multiplexing technology in the field of optical communication, greatly improved the transmission capacity and rate of system, realized the large capacity optical fiber transmission. Through the analysis of the principle of the WDM technology, the paper grasps the main performance parameters of the WDM. According to the design principle of the experimental circuit, the paper also combined with the design of the optical fiber communication transmiision transmitter and receiver circuit, designed and realized WDM in experiments in optical fiber communication. [ABSTRACT FROM AUTHOR]