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Design and Implementation of the module that generate Sync-signal for Controlling Tx/Rx Antenna of 2.3-2.7GHz WiMAX TDD Repeater (2.3-2.7GHz WiMAX용 TDD 중계기의 송수신 안테나 제어를 위한 동기 신호 생성 모듈 설계 및 구현)

  • Woo, Sang-Hee
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.1
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    • pp.60-63
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    • 2009

  • In this paper, Designed and implemented about module that generate division signal for uplink section and downlink section for controlling Tx/Rx antenna of 2.3-2.7GHz WiMAX TDD repeater. It is consisted of RF block and Baseband block, and because function of this module is that synchronize with WiMAX signal and create division signal for uplink section and downlink section, this module was designed only received path. And because of manufacturing of most RF block by one chip, this module could minimize area. And in baseband block, used the WiMAX Modem to detect Preamble and DL-MAP information of WiMAX signal. This design can process about 2.3-2.7GHz WiMAX.

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Downlink Power Allocation for Relay Frequency Reuse (릴레이 주파수재사용을 위한 하향링크 전력 자원 할당)

  • Oh, Chang-Yoon
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.6
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    • pp.98-104
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    • 2012

  • We consider the optimum power allocation problem for downlink system throughput maximization in a 2 time slotted relay interference channel. Base station (BS) transmits power to Mobile Station (MS) and Relay Station (RS) in time slot 1 (orthogonal channel). In time slot 2, BS and RS transmit power to each MS, while causing cochannel interference to each other. The obtained optimum power allocation scheme allows simultaneous transmissions of BS and RS when the interference level in time slot 2 is low. However, when the interference level is high, RS shuts down its power. Numerical results are provided to support our analysis.

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Fairness-insured Aggressive Sub-channel Allocation and Efficient Power Allocation Algorithms to Optimize the Capacity of an IEEE 802.16e OFDMA/TDD Cellular System

  • Ko, Sang-Jun;Chang, Kyung-Hi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.3 no.4
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    • pp.385-398
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    • 2009

  • This paper aims to find a suitable solution to joint allocation of sub-channel and transmit power for multiple users in an IEEE 802.16e OFDMA/TDD cellular system. We propose the FASA (Fairness insured Aggressive Sub-channel Allocation) algorithm, which is a dynamic channel allocation algorithm that considers all of the users' channel state information conditionally in order to maximize throughput while taking into account fairness. A dynamic power allocation algorithm, i.e., an improved CHC algorithm, is also proposed in combination with the FASA algorithm. It collects the extra downlink transmit power and re-allocates it to other potential users. Simulation results show that the joint allocation scheme with the improved CHC power allocation algorithm provides an additional increase of sector throughput while simultaneously enhancing fairness. Four frames of time delay for CQI feedback and scheduling are considered. Furthermore, by addressing the difference between uplink and downlink scheduling in an IEEE 802.16e OFDMA TDD system, we can employ the uplink channel information directly via channel sounding, resulting in more accurate uplink dynamic resource allocation.

  • https://doi.org/10.3837/tiis.2009.04.004 인용 PDF