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1,2,4-Triazole sodium is used as a multifunctional cathode sodiation additive in full-cells, which achieves a NaF-rich cathode electrolyte interface and also inspires a facile method to prepare free-standing electrodes.

Multimedia Broadcast Multicast Service (MBMS)-dedicated cell is a Long Term Evolution (LTE) based broadcast transmission mode with both high transmission efficiency and good compatibility with LTE unicast systems. However, since the physical design of Cell Acquisition Subframe (CAS), which is the control part of an MBMS-dedicated cell transmission period, does not take into account the long delay spread channels in Medium Tower Medium Power (MTMP) and High Tower High Power (HTHP) cells, receivers would probably suffer from multipath aliasing errors in practical transmission. This paper analyzes the impact of aliasing errors on channel estimation (CHE) accuracy and proposes an Aliasing-Elimination CHE algorithm for CAS reception. In the proposed algorithm, the pre-decoded Physical Broadcast Channel (PBCH) is reconstructed and utilized to generate a complete multipath distribution within the entire OFDM symbol length. By using this full-symbol length multipath distribution, the proposed algorithm eliminates aliasing errors effectively. Simulation results and complexity analysis show that the proposed CHE algorithm achieves a significant performance improvement compared to conventional CHE algorithms in long delay spread channels, with acceptable increment in complexity.

In Multimedia Broadcast Multicast Service (MBMS)-dedicated cell, multipath aliasing is an inevitable challenge for CAS reception in long delay spread channels. Meanwhile, traditional Channel Estimation (CHE) algorithms may not work well in such scenarios. For overcoming this problem, an Aliasing-Elimination CHE (AE-CHE) algorithm was proposed. This novel algorithm utilizes the pre-decoded Physical Broadcast Channel (PBCH) to generate a full-symbol length multipath distribution. By using the multipath distribution, aliasing errors could be eliminated effectively. However, previous researches are mainly based on ideal factors such as perfect PBCH decoding, static channel without Doppler spread, which does not match the actual situation in practical receivers. This paper studies the effects of actual PBCH decoding ability and Doppler spread of time-variant channels on the performance of the AE-CHE algorithm. Analysis and simulation results show that the AE-CHE algorithm could also outperform the traditional algorithms even in the presence of non-ideal factors.

The evolved Multimedia Broadcast Multicast Services, eMBMS (evolved Multimedia Broadcast Multicast Service), promises to be a powerful method for distributing common multimedia content. However, rapid deployment of 5G broadcating services in China cannot be supported by eMBMS due to the obstacles of regional simple deployment and one-way interface between core network and RAN (Radio Access Network) side. This article fills the gap by describing solutions for new core network architecture. Two innovative solutions realize the control plane function. The proposed architecture alternative satisfies the objective needs of radio and television service deployment in China and reduces the complexity of signaling processing, which is favorable for collaborative coverage of broadcast and unicast.

With the evolution of FeMBMS technology and the definition of new numerologies in 3GPP from Release 14 until now, physical performance of LTE-based terrestrial broadcast has been improved, such as larger geographic area with longer CP (Cyclic prefix) of 200μs or even 300μs applied for HPHT (High Power High Tower) compared with traditional unicast with CP of 16.67μs, however as for the limitation of OFDM modulation adopted in FeMBMS in high Doppler scenarios, it has to define another kind of numerology with larger sub-carrier spacing (CP of 100μs) to be published in R16 to support the mobility speed of 250km/h. It is not possible to support large area and high mobility speed in only one numerology at the current technological regime. OTFS (Orthogonal Time Frequency Space) modulation is famous for its performance in resisting high Doppler, this paper builds the bridge between OTFS and LTE-based terrestrial broadcast, and does research on OTFS modulation under the parameters of LTE-based terrestrial broadcast, including as follows. First, briefly introduces the background and development of OTFS modulation and its advantage over other traditional modulation. Basic principle and the signal processing flow of OTFS modulation is described in section II and section III. In the fourth part, this paper gives the development requirements of 5G broadcasting, furthermore, generates the simulation about OTFS system under the numerologies of LTE-based terrestrial broadcast published in R14, compared with OFDM performance individually in CAS and MBSFN mode. Simulation results and conclusions are given in section V.

In this paper, a Contour-based Cluster Identification (CCI) algorithm is proposed to identify the clusters in Concatenated Power Delay Profiles (CPDPs). To predict the characteristics of clusters, we introduce four methods to the three-fold CCI algorithm. Our new methods increase identification accuracy with greatly decreased computational complexity from 2-D to 1-D Hough-transform searching. The accuracy of prediction methods and the efficiency of the CCI algorithm are both confirmed by simulation results.

With the proliferation and diversification of mobile communication services, the current mobile broadband networks face severe challenges. The progressive video service that will make up the majority of future network traffic has more demands for transmission bandwidth, network capacity, and management flexibility. Moreover, denser connectivity, higher reliability, lower latency, and better interaction impose some great challenges to existing networks. In order to meet these growing demands, a promising approach is to integrate a broadcast network with a cellular network. In this article, we briefly set forth the latest progress on the cellular network and the broadcast network, respectively. Then the logic architecture of the integrated network is given to clarify the functional partitioning. In addition, the physical architecture of the integrated network is presented to enable coordination in different aspects. Some feasible strategies are discussed and several promising technologies are presented.

Home environment is suggested to be an essential influencing factor for asthma development or asthma exacerbation. However, the association between home environment and childhood asthma among preschool children in the hot humid subtropical region in South China is unclear. We investigated doctor-diagnosed asthma in preschool children due to the parental perception of odors in homes. A total of 1946 children aged from 3 to 6 years from 22 kindergartens in Foshan were randomly recruited for this study in May 2016. The associations among childhood asthma, indoor environment and parental perceptions of odors were examined by using logistic regression model in terms of odds ratio (OR) and 95% confidence interval (CI). Parental atopy had the highest risk for childhood asthma with odds ratio = 6.007 (95% CI: 2.369–15.231). Parental perception of dry air significantly increased asthma with odds ratio = 1.284 (95% CI: 1.027–1.606). The parental perceptions of odors were strongly related with new furniture at home. We conclude that parental perception of dry air is a risk factor for the increase of childhood asthma in the present study. Hence, our study indicates a need to control the household humidity level and reduce the usage of new furniture, in order to reduce the risk of childhood asthma in South China.

The aim of the present study was to transfect rat aortic smooth muscle cells with an early growth response factor-1 (Egr-1)-specific DNAzyme (ED5), to observe its effect on Egr-1 and proliferating cell nuclear antigen (PCNA) expression and to elucidate the mechanism of ED5-mediated inhibition of vascular smooth muscle cell (VSMC) proliferation. VSMCs in primary culture obtained by tissue block adhesion were identified by morphological observation and α smooth muscle actin (α-SM-actin) immunocytochemistry. The cells were then transfected with ED5 or scrambled ED5 (ED5SCR). The three groups of cells used in the present study were the control group, ED5 group and ED5SCR group. The expression levels of Egr-1 and PCNA protein were detected following transfection by analyzing and calculating the integral optical density value in each group. Primary culture of VSMCs and transfection of ED5 and ED5SCR were successfully accomplished. Following stimulation with 10% fetal calf serum, the Egr-1 protein was expressed most strongly at 1 h and demonstrated a declining trend over time; the expression of PCNA protein began at 4 h, peaked at 24 h and then demonstrated a slightly declining trend over time. Compared with the control group and the ED5SCR group, ED5 inhibited the expression of Egr-1 and PCNA (P

In this paper, we employ elementary methods to investigate the reciprocal sums of the products of two Fibonacci numbers in several ways. First, we consider the sums of the reciprocals of the products of two Fibonacci numbers and establish five interesting families of identities. Then we extend such analysis to the alternating sums and obtain five analogous results.

Broad-band absorption bleaching in erbium-doped fiber by in-band narrow-linewidth pumping is reported. For the first time, spectra of absorption bleaching of erbium-doped fiber is measured and the refractive index changes inferred through the Kramers–Kronig relations in this true two-level system in order to understand its operation in the external cavity of a laser.

The increasing demand for broadband mobile communications has generated interest in exploring new frequency bands and modifying network structures. In such systems, photonic technologies can bring both cost reduction as well as an increase in performance, mainly due to the low-loss properties of optical fibers. An optical source capable of producing tunable, high-quality microwave/mm-wave signals would be of great interest not only in such communications systems, but in fiber sensors and numerous other applications as well. One potentially cost-effective method to fabricate such a system is via optical heterodyning. In this approach, the difficulties in generating a high-quality signal are two-fold. The first issue is in maintaining a specific frequency difference (i.e. microwave signal) between the lasers for an extended period of time. The second is in narrowing the inherent linewidth of the laser from the MHz values typically produced by conventional semiconductor lasers, down to values practical for a communications system. Both of the above requirements are facilitated by the newly developed doped-fiber, external cavity laser (DFECL), which offers relatively stable single-longitudinal-mode operation in addition to narrow linewidth operation. This paper will demonstrate frequency locking of a DFECL using a delay-line discriminator. The RF linewidth, initially 10-15MHz, is reduced to levels conducive to optical PLL locking. Optical power levels are approximately -3 dBm and unamplified microwave power output levels are typically -35 dBm, depending on photodetector responsivity. Carrier-tonoise ratios are generally 40-45 dB. The physical mechanisms underlying the observed laser dynamics are discussed, including laser-to-fiber alignment and thermal fluctuations.

A doped fiber external cavity laser (DFECL) exhibits high power, narrow linewidth and stable wavelength which may be tuned. We demonstrate IEEE 802.11 signal transmission by direct modulating the ultra long DFECL at ~2.5GHz.

The doped fiber external cavity semiconductor laser (DFECL) has been reported with a simple structure, high power, narrow linewidth, and stable wavelength. The DFECL is mostly suitable to be an optical carrier generator for external modulation or microwave optical generation. Because of mode locking, the DFECL, with saturable absorber in its external cavity, has the possibility to be direct modulated at its multiples of cavity resonant frequency. The useful modulation frequency of the laser can be increased significantly. In this paper, we present experimental results about the transmission response of direct modulation of an ultra-long DFECL, and the modulated microwave signal transmission at the frequency of the 22nd. multiple of the cavity resonant frequency. Modulated narrow bandwidth microwave signals at 2.4GHz were transmitted by this DFECL. The received RF spectrum has no obvious distortion for a 10MHz narrow band microwave signal and, all the resonant and harmonic frequencies in the 0~2.5GHz region are 50 dB lower than the transmitted wave. The results show that narrowband modulated microwave can be transmitted at high frequency by the long DFECL; even through the cavity round-trip frequency is very low. We conclude that this ultra-long doped fiber external cavity semiconductor laser can be used for narrowband wireless communication with direct modulation.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We report on the first experiments of optical microwave generation by heterodyne beating of two doped-fiber semiconductor external-cavity lasers (DFECL). Our measurements show that minor side-mode beating in DFECL affect the optical heterodyne beat signal. Using the RF methods we study the side-mode suppression in the DFECL.

We present an experimental study of tuning characteristics and wavelength stability of a 1490 nm doped fiber external cavity laser. The standing wave in the erbium-doped fiber in an external-cavity laser causes spatial hole burning and absorption modulation and forms a dynamic grating. The dynamic grating can effectively suppress side modes and eliminate wavelength fluctuations in the laser. The operating wavelength of this hybrid laser is shown for the first time to our knowledge to be smoothly tunable by changing the semiconductor laser drive current or temperature.

We report on the spectral analysis of the first 1490 nm external cavity laser with an intra-cavity erbium-doped fiber. Self-mode beating and heterodyne beating methods are employed to measure the side mode suppression ratios and to study the effect of the rare-earth doped fiber on the spectrum of the external-cavity laser. Experimental and simulated results show a substantial decrease in the number of the external-cavity modes and a side-mode suppression ratio of >15 dB.