• Title/Summary/Keyword: Transmit power allocation

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Symbol Error Probability of a Physical Layer Network Coded System in Nakagami Fading Channels (나카가미 페이딩 채널에서 물리 계층 네트워크 부호화 시스템의 심볼 오류율)

  • Do, Phu Thinh;Wang, Jin-Soo;Park, Jin-Bae;Kim, Yun-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.8C
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    • pp.645-654
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    • 2012
  • In this paper, we consider a two-way relay (TWR) system, where two user nodes exchange their information within two transmission phases, by the help of a relay node adopting physical layer network coding. In the system, two users transmit their binary phase shift keying symbols simultaneously in the first phase, and the relay node decodes the XORed version of two user data and broadcasts it back to two users in the second phase. The performance of the system is analyzed in terms of the average end-to-end symbol error probability in Nakagami-m fading channels, for which a tight upper bound is derived in a closed form to provide an accurate and handy estimate on the performance. The results show that our upper bounds are almost indistinguishable from simulation results for various channel and system configurations. In addition, the optimal relay location and power allocation for various conditions can be obtained quickly with our analysis.

FH DFT-Spreading OFDM System for the Effective Channel Estimation and PAPR Reduction in Jamming Channel (재밍 채널에서 효과적 채널 추정과 PAPR 저감을 위한 주파수 도약 DFT-Spreading OFDM 시스템)

  • Kim, Jang-Su;Ryu, Heung-Gyoon;Lee, Seung-Jun;Ko, Dong-Kuk
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.7
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    • pp.796-804
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    • 2010
  • It is important to use the comb type pilot allocation for the continuous channel and efficient processing. And DFT-spreading OFDM is used a lot to solve high PAPR problem of OFDM system. However, PAPR is increased again when comb type pilot is used to estimate channel characteristics. So, in this paper, we employ a new SLM method to DFT-spreading OFDM system to reduce increased high PAPR. And we suggest an effective method to transmit side information without additional bandwidth. Pilot and side information must be preserved from jamming or intentional interferences since those are very important in DFT spread OFDM system using SLM. So, in this paper, we like to analyze and simulate the performance of DFT spread OFDM system based on SLM against jamming signal. To remedy the vulnerable shortcomings of DFT spread OFDM about jamming or intentional interferences, we employ FH(Frequency Hopping) method and analyze system performance under the several jamming conditions such as MTJ(Multi Tone Jamming) and PBJ(Partial Band Jamming).