• Title/Summary/Keyword: Trellis-Coded Modulation

Search Result 94, Processing Time 0.02 seconds

Analysis of a TC-16ADPSK Performance for Transmitting Different Information on One Channel Simultaneously (TC-16ADPSK을 사용한 이종 정보 동시 전송용 변조방식의 성능 분석)

  • 이원석;강희훈;이성백
    • Journal of the Institute of Electronics Engineers of Korea TE
    • /
    • v.37 no.5
    • /
    • pp.71-76
    • /
    • 2000
  • A TC-16ADPSK scheme for transmitting different kinds of information simultaneously is proposed in this paper. The scheme is designed for simultaneously transmitting two kinds of Information on one channel. In signal mapping, a data of two kinds of information is used to phase modulation on Star-16APSK constellation and the other to amplitude modulation. In detection, each data independently recovers from mixing signal on each detector Therefore, we can transmit two kinds of Information on one channel can be transmitted efficiently. BER performance of the proposed scheme is analyzed on AWGN channel and Rayleigh fading channels on a computer with Matlab communication toolbox. On same SNR, the Gray code mapping has more 0.5-1.5dB coding gains than Ungerboeck's code mapping gains.

  • PDF

A Study on the Implementation of the TCM DECODER for Next Generation Mobile Communication (차세대 이동통신을 위한 TCM 복호기 구현에 관한 연구)

  • 은도현;최윤석;조훈상;김응배;이순흠
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.5 no.1
    • /
    • pp.41-51
    • /
    • 2001
  • In this paper, we presented that the performance of the TCM(Trellis Coded Modulation) using the Euclidean distance is better than that of the convolutional code using the hamming distance under the same bandwidth efficiency. And the TCM DECODER for next generation mobile communication replacing the using convolutional decoder is implemented. Also, for the implementation of the TCM DECODER, the convolutional decoder and the TCM decoder were made by C-language and simulated under AWGN channel with respect to the hard decision and the soft decision. So we proved that performance of the TCM is better than that of the convolutional code. From this result, TCM DECODER, of which constraint length is 3, 5 or 7 and which use the soft decision method, was implemented using the AHDL(Altera Hardware Description Language) and fortified using the Max+plus H version 8.2 of Altera corporation.

  • PDF

Concatenated Diversity System for Bandwidth Efficient Communication of Flight Type Air Node in Unstable Channel Environments (비정형 통신 채널 환경에서 비행형 에어노드의 대역 효율적인 통신을 위한 연접 다이버시티 시스템)

  • Kang, Chul-Gyu;Park, Jin-Hee;Oh, Chang-Heon
    • Journal of Advanced Navigation Technology
    • /
    • v.16 no.2
    • /
    • pp.247-254
    • /
    • 2012
  • In this paper, we propose a concatenated diversity system to assure the data transmission reliability between flight type air nodes which move according to their atypical orbit, then its performance is analyzed using computer simulation and it is designed with hdl. The proposed system cannot only improve a bandwidth efficient and coding gain from diversity TCM code but also the reliability of data transmission is high. From the computer simulation result about bit error rate(BER) of the proposed system, we confirm that its BER performance is about 11dB greater than TCM code at $10^{-2}$ and about 11dB greater than space time block code at $10^{-3}$ which has a full diversity gain. In addition, when we compare its BER performance with space time trellis code which has both a diversity gain and a coding gain, the performance of the proposed system is greater than about 1.5dB at $10^{-5}$. Lastly, after designing the proposed system with HDL, we can confirm that the operation result is correct.

Design and Implementation of the Channel Adaptive Broadband MODEM (채널 적응형 광대역 모뎀 설계 및 구현)

  • Chang, Dae-Ig;Kim, Nae-Soo
    • The KIPS Transactions:PartC
    • /
    • v.11C no.1
    • /
    • pp.141-148
    • /
    • 2004
  • Recently, the demand of broadband communications such as high-speed internet, HDTV, 3D-HDTV and ATM backbone network has been increased drastically. For transmitting the broad-bandwidth data using wireless network, it is needed to use ka-band frequency. However, the use of this ka-band frequency is seriously affected to the received data performance by rain fading and atmospheric propagation loss at the Ka-band satellite communication link. So, we need adaptive MODEM to endure the degraded performance by channel environment. In this paper, we will present the structure and design of the 155Mbps adaptive Modem adaptively compensated against channel environment. In order to compensate the rain attenuation over the ka-band wireless channel link, the adaptive coding schemes with variable coding rates and the multiple modulation schemes such as trellis coded 8-PSK, QPSK, and BPSK are adopted. And the blind demodulation scheme is proposed to demodulate without Information of modulation mode at the multi-mode demodulator, and the fast phase ambiguity resolving scheme is proposed. The design and simulation results of adaptive Modem by SPW model are provided. This 155Mbps adaptive MODEM was designed and implemented by single ASIC chip with the $0.25\mu{m}$ CMOS standard cell technology and 950 thousand gates.