TD-SCDMA与TD-HSDPA共存系统性能评估研究

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“TD-SCDMA/TD-HSDPA共存系统性能评估,研究了两者在共存时的系统性能,包括重要模拟假设、部署场景、传播模型和干扰模型的描述,以及共存系统对容量的影响。” 这篇论文主要探讨了TD-SCDMA(时分同步码分多址)和TD-HSDPA(时分高速下行链路分组接入)两种技术在共存环境下的性能表现。TD-HSDPA是TD-SCDMA系统的演进版本,旨在提供更高的数据速率和网络容量,对于提升移动通信服务的质量至关重要。随着TD-SCDMA网络在中国的大规模部署,以及向TD-HSDPA的升级计划,研究两者之间的共存问题显得尤为重要。 作者黄云飞、韦再雪和杨大成在论文中详细分析了共存系统的关键因素。首先,他们描述了部署场景,这可能涉及到城市、郊区或农村等不同环境,这些环境对信号传播和干扰有着不同的影响。其次,他们引入了传播模型,这些模型用于模拟无线电信号在不同条件下的传播特性,如多径效应、阴影衰落和路径损耗等。 此外,论文还特别关注了干扰模型,因为TD-SCDMA和TD-HSDPA共存可能导致相互间的干扰,影响系统性能。这可能包括同频干扰、邻频干扰和时间同步误差导致的干扰。通过仿真,作者研究了这些干扰如何影响两个系统的容量和效率。 论文进一步深入探讨了共存系统对系统容量的影响。当TD-HSDPA系统与TD-SCDMA系统同时运行时,可能会导致资源的争夺,从而降低整体网络性能。作者通过分析提出了关于如何优化部署策略以减少这种负面影响的建议。 该研究为理解TD-SCDMA和TD-HSDPA共存的挑战提供了有价值的见解,为网络规划者和工程师提供了理论依据,有助于他们在实际部署中做出更明智的决策,以确保服务质量并最大限度地提高网络资源的利用效率。这项工作强调了在技术演进过程中,充分考虑现有系统和新系统的兼容性问题的重要性,这对于未来移动通信网络的健康发展具有重要意义。

润色下面英文:The controlled drug delivery systems, due to their precise control of drug release in spatiotemporal level triggered by specific stimulating factors and advantages such as higher utilization ratio of drug, less side-effects to normal tissues and so forth, provide a new strategy for the precise treatment of many serious diseases, especially tumors. The materials that constitute the controlled drug delivery systems are called “smart materials” and they can respond to the stimuli of some internal (pH, redox, enzymes, etc.) or external (temperature, electrical/magnetic, ultrasonic and optical, etc.) environments. Before and after the response to the specific stimulus, the composition or conformational of smart materials will be changed, damaging the original balance of the delivery systems and releasing the drug from the delivery systems. Amongst them, the photo-controlled drug delivery systems, which display drug release controlled by light, demonstrated extensive potential applications, and received wide attention from researchers. In recent years, photo-controlled drug delivery systems based on different photo-responsive groups have been designed and developed for precise photo-controlled release of drugs. Herein, in this review, we introduced four photo-responsive groups including photocleavage groups, photoisomerization groups, photo-induced rearrangement groups and photocrosslinking groups, and their different photo-responsive mechanisms. Firstly, the photocleavage groups represented by O-nitrobenzyl are able to absorb the energy of the photons, inducing the cleavage of some specific covalent bonds. Secondly, azobenzenes, as a kind of photoisomerization groups, are able to convert reversibly between the apolar trans form and the polar cis form upon different light irradiation. Thirdly, 2-diazo-1,2-naphthoquinone as the representative of the photo-induced rearrangement groups will absorb specific photon energy, carrying out Wolff rearrangement reaction. Finally, coumarin is a promising category photocrosslinking groups that can undergo [2+2] cycloaddition reactions under light irradiation. The research progress of photo-controlled drug delivery systems based on different photo-responsive mechanisms were mainly reviewed. Additionally, the existing problems and the future research perspectives of photo-controlled drug delivery systems were proposed.

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