In this article we analyze performance of VoIP services over 1xEVdO-revision A (dO-rev A) networks and show that high-quality VoIP with unconstrained mobility and high capacity can be achieved. Together with quality o...
详细信息
In this article we analyze performance of VoIP services over 1xEVdO-revision A (dO-rev A) networks and show that high-quality VoIP with unconstrained mobility and high capacity can be achieved. Together with quality of service (QoS) requirements, we emphasize practical issues such as mobility, degradation of feedback-channel quality, and packet overheads. Novel techniques are presented for voice processing such as smart blanking and adaptive dejitter playback buffer with time warping. These techniques help to meet QoS constraints to achieve a circuitlike voice quality while improving overall capacity. detailed end-to-end simulations are presented and system capacity is analyzed under the QoS and system stability constraints. We claim that dO-rev A can provide VoIP capacity comparable to circuit-switched cellular CdMA technologies (e.g., IS-2000) and simultaneously carry significant amount of other types of traffic such as non-delay sensitive applications anddownlink multicast.
作者:
CHArLES J. ArNTZENrICHArd T. M AHONEYAbout the authors: Charles Arntzen was appointed to the Florence Ely Nelson Presidential Endowed Chair at Arizona State Univ. in Tempe in 2000. He also serves as the Founding Director of the Arizona Biomedical Institute. Prior to joining ASU
Dr. Arntzen was the president and CEO of the Boyce Thompson Institute for Plant Research in Ithaca New York. He has served on many national and international committees including service as Chairman of the National Institutes of Health's Biotechnology Policy Board and as Chair of the Biobased Industrial Products Committee for the National Academy of Sciences. He was elected to the US National Academy of Sciences in 1983 and to the National Academy of India the following year. He currently serves as a member of President George W. Bush's Council of Advisors on Science & Technology. Richard Mahoney joined the faculty of Arizona State Univ. in 2002 and with Dr. Arntzen is the co-founder of the proVacs (production of Vaccines using Applied Crop Science) Center. He has been an international pioneer in public sector management of intellectual property and in policy issues related to the global introduction of vaccines. He formerly served as Vice President of PATH (the Program for Appropriate Technology in Health Seattle
Washington) as chairman of the International Task Force on Hepatitis B Immunization and as co-founder and Chief Development and Administrative Officer of IVI (the International Vaccine Institute Seoul
Korea). He has spent the past 15 years focusing on vaccine production and supply issues and has identified intellectual property as a crucial element in assuring vaccine supply to the developing world. Based upon this experience he was the architect of recently created the Center for Management of Intellectual Property in Health R&D (MIHR) program which is based in London England. Their mailing address is: Arizona Biomedical Institute Arizona State Univ. PO Box 871601 Tempe AZ 85287-1601 USA.
The small-signal conductance technique was extended to extract asymmetric source/drain parasitic resistances. It was also applied in order to analyze the t Wrdelay of drAM cell transistors in production and to devel...
详细信息
The small-signal conductance technique was extended to extract asymmetric source/drain parasitic resistances. It was also applied in order to analyze the t Wrdelay of drAM cell transistors in production and to develop a non-planar cell transistor such as recessed access device (rAd) for low-powerdrAM cells. Factors limiting the drive current for planar and non-planar access transistors in the low-powerdrAM cells were discussed
This paper presents a novel 20V/40V symmetrical vertical trench MOS (SVT MOS) having both drain extension and gate realized in vertical direction respect to the silicon surface. Using silicon depth to realize the gate...
详细信息
This paper presents a novel 20V/40V symmetrical vertical trench MOS (SVT MOS) having both drain extension and gate realized in vertical direction respect to the silicon surface. Using silicon depth to realize the gate and to withstand high voltage, carefully designing doping implants andrealizing a vertical field oxide, it was possible to reduce more than 60% the device pitch (i.e. spacing between half drain contact and half source contact) maintaining the same performance of equivalent lateral device
800 kV HVdC is economically attractive for bulk power transmission of 6000 MW and even 9000 MW per bipole overdistances up to 3000 km. With the present progress of r&d converter equipment for 800 kV HVdC will be ...
详细信息
800 kV HVdC is economically attractive for bulk power transmission of 6000 MW and even 9000 MW per bipole overdistances up to 3000 km. With the present progress of r&d converter equipment for 800 kV HVdC will be qualified within short. With proper separation and proper structure of the control and protection and auxiliary systems, the reliability and availability will be as good as, or even better than, for converters at lower voltages.
Advancedring type technology and encapsulating scheme were developed to fabricate highly manufacturable andreliable 256Mb PrAM. Very uniform BEC area was prepared by the advancedring type technology in which core d...
详细信息
ISBN:
(纸本)142440004X
Advancedring type technology and encapsulating scheme were developed to fabricate highly manufacturable andreliable 256Mb PrAM. Very uniform BEC area was prepared by the advancedring type technology in which core dielectrics were optimized for cell contact CMP process. In addition, relatively high set resistance was stabilized from encapsulating Ge 2 Sb 2 Te 5 (GST) stack with blocking layers, thus giving rise to a wide sensing window. These advancedring type and encapsulating technologies can provide great potentials of developing high density 512Mb PrAM and beyond
There are number of mechanisms and algorithms available to achieve ad hoc communication. However, establishing communication between heterogeneous networks with fragile connectivity, is still a challenging task. Exist...
详细信息
There are number of mechanisms and algorithms available to achieve ad hoc communication. However, establishing communication between heterogeneous networks with fragile connectivity, is still a challenging task. Existing transport protocols like TCP are not well suited to networks with instable bandwidth and connectivity. In such environments, services cannot be reliably offered and hence more intelligent protocols and architectures should be used. For such scenarios, we study the feasibility of using opportunistic forwarding to achieve end-to-end communication. In this paper, we investigate the usage of delay tolerant networks based protocols for achieving reliable communication in such scenarios. Specifically, we study the provision of emergency services and show how mobile users could make use of the ad hoc peers to reach an appropriate answering point e.g., public safety answering point using the delay tolerant approach. Moreover, we have extended the usage of dTN for complementary services such as buddy communication.
The HOPping Field Emission display (HOPFEd) is a new architecture for field emission displays. The main difference between a conventional Field Emission display (FEd) device and a ItOPFEd lies in the spacer struct...
详细信息
The HOPping Field Emission display (HOPFEd) is a new architecture for field emission displays. The main difference between a conventional Field Emission display (FEd) device and a ItOPFEd lies in the spacer structure. In a HOPFEd, two dielectric plates, named hop and flu spacer, are sandwiched between the emitter and the front plate. The objective of this spacer structure is to improve the performance oF a FEd substantially with notable contrast, color purity and luminance uniformity. In order to optimize the structure of the device and to make the electron spot on the screen match the requirement of the phosphordot dimension, the influence of electrical and structural parameters of the device on the electron spot profile was studied by numerical simulation in this paper. Monte Carlo method was employed to calculate the potential distribution inside hop and flu spacers due to secondary electrons mechanism plays an important role in HOPFEd. The results indicated that the potential distribution in the spacers and spot profile depended strongly on the hop voltage, anode voltage and spacer's layout. This study may provide a useful theoretical support for optimizing the structure in HOPFEd.
An electroplating pure tin bumping technology has been developed in house with commercial chemicals. Sputtered TiW and Cu were used as under bump metallurgy (UBM). The tin bumps were peripheral distributed on the die....
详细信息
An electroplating pure tin bumping technology has been developed in house with commercial chemicals. Sputtered TiW and Cu were used as under bump metallurgy (UBM). The tin bumps were peripheral distributed on the die. The electroplated bumps had mushroom shape, and the height is about 70mum. The as-reflow bumps had sleek shape, and the diameter is about 100mum. For as-reflow bumps, scanning electron microscope was used for observing the microstructure of interface, and energy dispersive X-ray microanalysis was used for investigating the composition of the intermetallic compounds. Multireflow tests were used as accelerating tests for tin bumps. The samples reflowed 1 times to 10 times respectively. Ball shear tests were used for evaluate the strength of different samples of multi-reflow tests. There are two layers of intermetallic compounds between copper and tin, which are Cu6Sn5 and Cu3Sn. For as-reflow bumps, the thickness of Cu3Sn layer is too thin to detect, and its growth need additional contact time. As the reflows time increased, Cu6Sn5 and Cu3Sn layers both grow, and the thickness of Cu6Sn5 is thicker than that of Cu3Sn. The total thickness of intermetallic compound has an exponential relationship with the times of reflow. The mechanism of intermetallic compounds growth is the diffusion of liquid tin to solid copper. The simplifieddiffusion model in the intermetallic interface is similar to one dimension nonequilibrium diffusion in the plate. The shear strength results of different samples which had multireflow tests were found to have little discrepancy with each other, that means the performance of tin bumps were stable
暂无评论