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Cellular Mobile Radio
Published in Michel Daoud Yacoub, Foundations of Mobile Radio Engineering, 2019
One of the many advantages of the cellular architecture is its modular growth capability. A start-up system is usually constituted of hexagonal cells of the largest possible radii. As the demand for service grows, the system will tend to absorb the new users up to a limit where it can still offer a good grade of service. If the quality of the service is initially high, it may be possible to accept an increase of the traffic load and allow a system performance degradation, but still within acceptable levels. This, in fact, constitutes a very convenient way of allowing the system to adapt to a sudden growth of the traffic demand. However, this adaptation is only efficient on a short-term basis, because any additional growth can cause a disastrous degradation. The network will be able to accommodate more subscribers if there is a change in the system itself. We shall examine some of the techniques that may be used.
Beyond-CMOS Devices
Published in Krzysztof Iniewski, Tomasz Brozek, Krzysztof Iniewski, Micro- and Nanoelectronics, 2017
Memory and logic are two essential parts of any computational system. General-purpose computers today are all based on a Von Neumann architecture with separate memory and logic units communicating through interconnects. Increasing speed disparity between logic and memory has become a major limit for system performance, which is further deteriorated by interconnect delays. Historically, Von Neumann also proposed a cellular array architecture formed by an array of identical units each with its own computing and memory components, as shown in Figure 10.5. Cells interact with their nearest neighbors and the state of a cell is certain functions of the states of its neighbors. An obvious advantage of cellular architecture is the replacement of long interconnects by many short local interconnects. The regular layout and uniform structures would also benefit manufacturing by eliminating complex geometries. The repeated units with reduced complexity could help to simplify system design. It has been shown that cellular architectures can perform arbitrarily complex tasks once cells surpass a certain internal complexity threshold [103]. Cellular architectures may also have enhanced defect and fault tolerances through reconfigurable designs.
Enhancements in Second Generation Systems
Published in Jerry D. Gibson, The Communications Handbook, 2018
Cellular: Refers to public land mobile radio networks for generally wide area (e.g., national) coverage, to be used with medium- or high-power vehicular mobiles or portable stations and for providing mobile access to the Public Switched Telephone Network (PSTN). The network implementation exhibits a cellular architecture which enables frequency reuse in nonadjacent cells.
Tailoring electrospun nanofibrous materials for oil/water emulsion separation
Published in The Journal of The Textile Institute, 2022
Jichao Zhang, Lifang Liu, Yang Si, Shichao Zhang, Jianyong Yu
The nanofibrous aerogels with 3 D interconnected pore structure are the new type of nanofibrous filtration materials, and have captured tremendous attention in oil/water emulsion separation. The tortuous transfer channel of aerogel facilitated emulsified droplet coalescence and interception, resulting in high separation efficiency. In contrast to the membrane with 2 D pore structure, aerogels with 3 D open-cell cellular architecture and ultrahigh porosity (>98%) can offer much stereo room for droplets storage, which effectively avoid rapidly pore plugging during separation process leading to high permeance (Zhang, Liu et al., 2021). Generally, there are two well-established methods for preparing nanofibrous aerogels.