Restrictions on Wideband Systems of Mobile Communications of New Generations at Declared Expansion of Data Transfer Rates

Author(s):  
Vladimir Mordachev
Author(s):  
Athanassios C. Iossifides ◽  
Spiros Louvros

Mobile broadband communications systems have already become a fact during the last few years. The evolution of 3G Universal Mobile Telecommunications Systems (UMTS) towards HSDPA/HSUPA systems have already posed a forceful solution for mobile broadband and multimedia services in the market, making a major step ahead of the main competitive technology, that is, WiMax systems based on IEEE 802.16 standard. According to the latest analyses (GSM Association, 2007; Little, 2007), while WiMax has gained considerable attention the last few years, HSPA is expected to dominate the mobile broadband market. The main reasons behind this forecast are: • HSPA is already active in a significant number of operators and is going to be established for the majority of mobile broadband networks worldwide over the next five years, while commercial WiMax systems are only making their first steps. • Mobile WiMax is a competitive technology for selection by operators in only a limited number of circumstances where conditions are favourable. Future mobile WiMax systems may potentially achieve higher data transfer rates than HSPA, though cell coverage for these rates is expected to be substantially smaller. In addition, WiMax technology is less capable in terms of voice traffic capacity, thus limiting market size and corresponding revenues. • In order to overcome the aforementioned disadvantages, WiMax commercial launches are expected to introduce a relative CAPEX disadvantage of at least 20–50% comparing to HSPA, in favorable cases, while there are indications of an increase by up to 5–10 times when accounting for rural areas deployments. The short commercial history of HSDPA (based on Rel.5 specifications of 3GPP) started in December of 2005 (first wide scale launch by Cingular Wireless, closely followed by Manx Telecom and Telekom Austria). Bite Lietuva (Lithuania) was the first operator that launched 3.6 Mbps. HSUPA was first demonstrated by Mobilkom Austria in November 2006 and soon launched commercially in Italia by 3 in December 2006. Mobilkom Austria launched the combination of HSDPA at 7.2 Mbps and HSUPA in February 2007. By September of 2007, less than two years after the first commercial launch, 141 operators in 65 countries (24 out of 27 in EU) have already gone commercial with HSDPA with 38 operators among them supporting a 3.6 Mbps downlink. In addition, devices supporting HSDPA/HSUPA services are rapidly enriched. 311 devices from 79 suppliers have already been available by September 2007, including handsets, data cards, USB modems, notebooks, wireless routers, and embedded modules (http://hspa.gsmworld.com).


2001 ◽  
Vol 674 ◽  
Author(s):  
Ralf Detemple ◽  
Inés Friedrich ◽  
Walter Njoroge ◽  
Ingo Thomas ◽  
Volker Weidenhof ◽  
...  

ABSTRACTVital requirements for the future success of phase change media are high data transfer rates, i.e. fast processes to read, write and erase bits of information. The understanding and optimization of fast transformations is a considerable challenge since the processes only occur on a submicrometer length scale in actual bits. Hence both high temporal and spatial resolution is needed to unravel the essential details of the phase transformation. We employ a combination of fast optical measurements with microscopic analyses using atomic force microscopy (AFM) and transmission electron microscopy (TEM). The AFM measurements exploit the fact that the phase transformation from amorphous to crystalline is accompanied by a 6% volume reduction. This enables a measurement of the vertical and lateral speed of the phase transformation. Several examples will be presented showing the information gained by this combination of techniques.


2021 ◽  
Vol 1 (132) ◽  
pp. 136-144
Author(s):  
Volodymyr Khandetskyi ◽  
Dmutro Sivtsov ◽  
Kostjantun Panin

Analysis of new technologies IEEE 802.11ac/ax of wireless networks showed that increasing their noise immunity is an actual task. The article studies the efficiency of fragmented data frames transmission. Comparison of the efficiencies in the case of retransmission of the corrupted original frame and in the case of its fragmentation in a wide range of the physical data transfer rates is carried out.


Author(s):  
Yao Yuan ◽  
Dalin Zhang ◽  
Lin Tian ◽  
Jinglin Shi

As a promising candidate of general-purpose transport layer protocol, the Stream Control Transmission Protocol (SCTP) has its new features such as multi-homing and multi-streaming. SCTP association can make concurrent multi-path transfer an appealing candidate to satisfy the ever increasing user demands for bandwidth by using Multi-homing feature. And multiple streams provide an aggregation mechanism to accommodate heterogeneous objects, which belong to the same application but may require different QoS from the network. In this paper, the authors introduce WM2-SCTP (Wireless Multi-path Multi-flow - Stream Control Transmission Protocol), a transport layer solution for concurrent multi-path transfer with parallel sub-flows. WM2-SCTP aims at exploiting SCTP's multi-homing and multi-streaming capability by grouping SCTP streams into sub-flows based on their required QoS and selecting best paths for each sub-flow to improve data transfer rates. The results show that under different scenarios WM2-SCTP is able to support QoS among the SCTP stream, and it achieves a better throughput.


Author(s):  
Francesco Pacini ◽  
Giacomo Paoli ◽  
Iván Cayón ◽  
Tamara Rivera ◽  
Beatriz Sarmiento ◽  
...  

The management of a heterogeneous mix of underwater vehicles needs a robust and reliable communication network, able to connect the remote command and control station (typically ashore or on board of a support ship) with nodes and vehicles in the deep sea. On the basis of this scenario, the infrastructure shall satisfy requirements such as: medium to extremely long distances between the control room and the area of operation; management of a variable number and type of nodes and vehicles (mobile, fixed, underwater, surfaced); a guaranteed bandwidth to send commands and receive platform status and tasks execution information with minimum latency; a high bitrate to transfer sensor data, pictures and videos in “near real time”; etc. Compared to the available solutions used nowadays for radio communication systems, the underwater environment imposes several constraints on the maximum achievable bandwidth and distance, drastically reducing data transfer rates. This means that the full communication network is a trade-off between different requirements and performances. The SWARMs project approach to this problem is to select, combine and integrate different and heterogeneous communication technologies, components and solutions, in order to obtain the best performances for the management and control of underwater vehicles during the execution of different missions and tasks. The network is mainly based on commercial components, but specific adaptations were made in order to fulfil the requirements of ad hoc underwater and overwater sub networks in maritime specific scenarios. Several experiments and sea trials have allowed the verification of the performance of the full network and the optimization of its configuration according to the mission needs.


2014 ◽  
Vol 18 (1) ◽  
Author(s):  
Nathanael Sabbah ◽  
Sinclair Wynchank

This article presents a description of tele-nuclear medicine and, after outlining its history, a wide, representative range of its applications. Tele-nuclear medicine has benefited greatly from technological progress, which for several decades has provided greater data transfer rates and storage capacity at steadily decreasing cost. Differences in the practice of nuclear medicine between developed and developing countries arise mainly from disparities in their available infrastructure, funding and education levels of personnel involved. Consequently there are different emphases in their tele-nuclear medicine, which are elaborated. It is concluded that tele-nuclear medicine is important for all countries, but the emphasis on its application may differ between developed and developing nations, with an emphasis on distance learning in the latter.


2010 ◽  
Vol 143-144 ◽  
pp. 698-702
Author(s):  
Li Tu ◽  
Jun'an Liu ◽  
Juan Juan Song

This paper Introduces a simple and reliable method to connect an ordinary twisted pair RS-232 up to 2048 devices and transmit the communication data more than 10 kilometers by using ZLGCAN interface card, CAN232MB converters and other equipment. The virtual serial port server makes use of CAN-bus network for data communications, guaranteeing the reliability of communic-ation, improving the RS-232 transmission distance, and simplifying the wiring process. Meanwhile user’s operation of the virtual serial port and a standard PC are compatible with the basic serial port operation. However, if there is a large number of continuous transmission of data to the case, the ac-tual serial data transfer rates is determined by the number of virtual serial port.


2021 ◽  
Vol 2086 (1) ◽  
pp. 012054
Author(s):  
A Sh Gazaliev ◽  
M V Moskotin ◽  
V V Belosevich ◽  
M G Rybin ◽  
I A Gayduchenko ◽  
...  

Abstract The growing requirements for mobile communication networks (data transfer rates over 100 Gbps) makes it necessary to use carrier signal with a frequency of at least 100 GHz. This requires the development of cheap and broadband sub-terahertz (sub-THz) detectors. Here we report on our recent efforts toward the development of a heterodyne sub-THz detector based on a single layer graphene two-terminal device integrated with a bowtie antenna on a sapphire substrate. Our detector operates at frequency of 140 GHz, which corresponds to the maximum transmission of THz radiation in the Earth’s atmosphere. The heterodyne detection is achieved by quasi-optical coupling of signals from two sub-THz radiation sources to the same detector. The measured frequency bandwidth is 5.8 GHz.


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