• 제목/요약/키워드: Cellular Systems

검색결과 1,298건 처리시간 0.031초

Erlang and Channel Capacity of Truncated Power Controlled CDMA Cellular Systems with Base Station Antenna Arrays

  • Kim, Nam-Soo
    • 한국통신학회논문지
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    • 제28권10A호
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    • pp.788-795
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    • 2003
  • We analyze the performance of a truncated power controlled CDMA(code division multiple access) cellular systems with base station antenna arrays. Erlang capacity and the channel capacity which is a maximum date rate to maintain almost error free communication are analytically derived. The numerical results show there can be a substantial increase in Erlang capacity and in channel capacity by antenna arrays incorporating with the truncated power control scheme.

진화하는 셀룰라 오토마타 신경망의 하드웨어 구현에 관한 연구 (A Study on Implementation of Evolving Cellular Automata Neural System)

  • 반창봉;곽상영;이동욱;심귀보
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2001년도 추계학술대회 학술발표 논문집
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    • pp.255-258
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    • 2001
  • This paper is implementation of cellular automata neural network system which is a living creatures' brain using evolving hardware concept. Cellular automata neural network system is based on the development and the evolution, in other words, it is modeled on the ontogeny and phylogeny of natural living things. The proposed system developes each cell's state in neural network by CA. And it regards code of CA rule as individual of genetic algorithm, and evolved by genetic algorithm. In this paper we implement this system using evolving hardware concept Evolving hardware is reconfigurable hardware whose configuration is under the control of an evolutionary algorithm. We design genetic algorithm process for evolutionary algorithm and cells in cellular automata neural network for the construction of reconfigurable system. The effectiveness of the proposed system is verified by applying it to time-series prediction.

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Resource Allocation for Device-to-Device Communications Reusing Uplink in Cellular Networks

  • Radwan, Amr
    • 한국멀티미디어학회논문지
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    • 제18권12호
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    • pp.1468-1474
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    • 2015
  • Efficient spectrum sharing is an important issue in Device-to-Device (D2D) communications underlaying cellular networks as it can mitigate the interference to cellular users and improve the performance of the systems. In this paper, we formulate the radio resource allocation in D2D communications as a mixed nonlinear integer programing. We show the formulated problem is NP-hard and thus a polynomial time algorithm to solve is not possible. Since such a problem is very hard to obtain the optimal solution within a short running time, we instead propose a fast heuristic suboptimal algorithm to mitigate the interference caused to cellular users and improve the performance of the systems. Simulation results are provided to evaluate the performance of the proposed algorithm.

패턴 인식을 위한 진화 셀룰라 분류기 (Evolvable Cellular Classifiers for pattern Recognition)

  • 주재호;신윤철;강훈
    • 한국지능시스템학회논문지
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    • 제10권4호
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    • pp.379-389
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    • 2000
  • A cellular automaton is well-known for self-organizing and dynamic behavions in the filed of artifial life. This paper addresses a new neuronic architecture called an evolvable celluar classifier which evolves with the genetic rules (chromosomes) in the non-uniform cellular automata. An evolvable cellular classifier is primarily based on cellular programming, but its mechanism is simpler becaise it utilizes only mutations for the main genetic operators and resmbles the Hopfield network. Therefore, the desirable bit-patterns could be obtained through evolutionary processes for just one individual agent, As a rusult, an evolvable hardware is derived which is applicable to clessification of bit-string information.

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The Design of an Intelligent Assembly Robot System for Lens Modules of Phone Camera.

  • Song, Jun-Yeob;Lee, Chang-Woo;Kim, Yeong-Gyoo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.649-652
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    • 2005
  • The camera cellular phone has a large portion of cellular phone market in recent year. The variety of a customer demand makes a fast model change and the spatial resolution is changed from VGA to multi-mega pixel. The 1.3 mega pixel (MP) camera cellular phone was first released into the Korean market in October 2003. The major cellular phone companies released a 2MP camera cellular phone that supports zoom function and a 2MP camera cellular phone is settled down with the Korea cellular phone market. It makes a keen competition in price and demands automation for phone camera module. There is an increasing requirement for the automatic assembly to correspond to a fast model change. The hard automation techniques that rely on dedicated manufacturing system are too inflexible to meet this requirement. Therefore in this study, this system is designed with the flexibility concept in order to cope with phone camera module change. The system has a same platform that has X-Y-Z motion or X-Z motion with ${\mu}m$order accuracy. It has a special gripper according to the type of a component to be put together. If the camera model changes, the gripper may be updated to fit for the camera module. The controller of this system acquires the data sets that have the information about the assembly part by the tray. This information is obtained ahead of an inspection step. The controller excludes an inferior part to be assembled by using this information to diminish the inferior goods. The assembly jig used in this system has a function of self adjustment that reduces the tact time and also diminish the inferior goods. Finally, the intelligent assembly system for phone camera module will be designed to get a flexibility to meet model change and a high productivity with a high reliability.

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Applications of Intelligent Radio Technologies in Unlicensed Cellular Networks - A Survey

  • Huang, Yi-Feng;Chen, Hsiao-Hwa
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권7호
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    • pp.2668-2717
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    • 2021
  • Demands for high-speed wireless data services grow rapidly. It is a big challenge to increasing the network capacity operating on licensed spectrum resources. Unlicensed spectrum cellular networks have been proposed as a solution in response to severe spectrum shortage. Licensed Assisted Access (LAA) was standardized by 3GPP, aiming to deliver data services through unlicensed 5 GHz spectrum. Furthermore, the 3GPP proposed 5G New Radio-Unlicensed (NR-U) study item. On the other hand, artificial intelligence (AI) has attracted enormous attention to implement 5G and beyond systems, which is known as Intelligent Radio (IR). To tackle the challenges of unlicensed spectrum networks in 4G/5G/B5G systems, a lot of works have been done, focusing on using Machine Learning (ML) to support resource allocation in LTE-LAA/NR-U and Wi-Fi coexistence environments. Generally speaking, ML techniques are used in IR based on statistical models established for solving specific optimization problems. In this paper, we aim to conduct a comprehensive survey on the recent research efforts related to unlicensed cellular networks and IR technologies, which work jointly to implement 5G and beyond wireless networks. Furthermore, we introduce a positioning assisted LTE-LAA system based on the difference in received signal strength (DRSS) to allocate resources among UEs. We will also discuss some open issues and challenges for future research on the IR applications in unlicensed cellular networks.

1차원 셀룰러 오토마타에 의한 진화시스템의 설계 및 구현 (A Desing and Implementation of the Evolution System by one dimensional Cellular Automata)

  • 박정희
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1996년도 추계학술대회 학술발표 논문집
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    • pp.263-266
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    • 1996
  • Cellular Automata are a discrete mathematical system whose evolution is governed by a deterministic rule involving local interactions. In this paper, one designed and implemented the evolution system based on GUI which can analyse how random intitial stated evolve easily.

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셀 생산 시스템의 통합 구조 (An integrated framwork for a cellular manufacturing system)

  • 이노성;임춘우
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.89-92
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    • 1997
  • The objective of this paper is to provide an alternative framework for the integration of process planning and scheduling in cellular manufacturing. The concept of an integrated cellular manufacturing system is defined and the system architecture is presented. In an integrated cellular manufacturing system, there are three modules : the process planning module, the manufacturing-cell design module, and the cell-scheduling module. For each module, the tasks and their activities are explained.

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Energy Efficiency Analysis of Cellular Downlink Transmission with Network Coding over Rayleigh Fading Channels

  • Zhu, Jia
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권3호
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    • pp.446-458
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    • 2013
  • Recently, energy-efficient cellular transmission has received considerable research attention to improve the energy efficiency of wireless communication. In this paper, we consider a cellular network consisting of one base station (BS) and multiple user terminals and explore the network coding for enhancing the energy efficiency of cellular downlink transmission from BS to users. We propose the network coded cellular transmission scheme and conduct its energy consumption analysis with target outage probability and data rate requirements in Rayleigh fading environments. Then, the energy efficiency in Bits-per-Joule is further defined and analyzed to evaluate the number of bits delivered per Joule of energy cost. Numerical results show that the network coded cellular transmission significantly outperforms the traditional cellular transmission in terms of energy efficiency, implying that given a Joule of energy cost, the network coded cellular transmission scheme can deliver more bits than the traditional cellular transmission.