• Title/Summary/Keyword: MAP Decoder

Search Result 89, Processing Time 0.022 seconds

The Combined AMC-MIMO System with Optimal Turbo Coded V-BLAST Technique to Improve Throughput and SNR (전송률 향상 및 SNR 개선을 위한 최적의 터보 부호화된 V-BLAST 기법을 적용한 AMC-MIMO 결합시스템)

  • Ryoo, Sang-Jin;Lee, Kyung-Hwan;Choi, Kwang-Wook;Lee, Keun-Hong;Hwang, In-Tae;Kim, Cheol-Sung
    • Journal of Internet Computing and Services
    • /
    • v.8 no.4
    • /
    • pp.61-70
    • /
    • 2007
  • In this paper, we propose and observe the Adaptive Modulation system with optimal Turbo Coded V-BLAST(Vertical-Bell-lab Layered Space-Time) technique that is applied the extrinsic information from MAP Decoder in decoding Algorithm of V-BLAST: ordering and slicing. And comparing the proposed system with the Adaptive Modulation system using conventional Turbo Coded V-BLAST technique that is simply combined V-BLAST with Turbo Coding scheme, we observe how much throughput performance and SNR has been improved. In addition, we show that the proposed system using STD(Selection Transmit Diversity) scheme results in on improved result, By using simulation and comparing to conventional Turbo Coded V-BLAST technique with the Adaptive Modulation systems, the optimal Turbo Coded V-BLAST technique with the Adaptive Modulation systems has SNR gain over all SNR range and better throughput gain that is about 350Kbps in 11dB SNR range. Also, comparing with the conventional Turbo Coded V-BLAST technique using 2 transmit and 2 receive antennas, the proposed system with STD scheme show that the improvement of maximum throughput is about 1.77Mbps in the same SNR range and the SNR gain is about 5.88dB to satisfy 4Mbps throughput performance.

  • PDF

Efficient Local Decoding Using Bit Stream Map for High Resolution Video (비트 스트림 지도를 이용한 고해상도 영상의 효율적인 지역복호화)

  • Park Sungwon;Won Jongwoo;Lee Sunyoung;Kim Wookjoong;Kim Kyuheon;Jang Euee S
    • Journal of Broadcast Engineering
    • /
    • v.9 no.4 s.25
    • /
    • pp.391-401
    • /
    • 2004
  • In this paper, we introduce a novel coding method to efficiently enable spatial random access for high resolution video. In terms of resolution and display size, standard display devices (such as cathode-ray tubes. monitors. PDAs, and LCDs) do not sufficiently support high resolution video such as digital cinema and panoramic video. Currently, users have no choice but to view video at lower resolution as a result of down-sampling, or only a partial region of the video due to display size limitations. Our proposed method. which we call the B-map, represents the set of starting locations of the coded segments in a picture frame. This information, or B-map, is first sent to the decoder prior to the coded data stream of the frame and is then used for fast local decoding. To test our method, we compare our B-map with JPEG tiling and the JPEG Resynchronization marker. Experimental results show that the proposed coding method requires less overhead than existing methods during the same decoding time. The results show promise for future panoramic or digital cinema applications.

Design of Low-Density Parity-Check Codes for Multiple-Input Multiple-Output Systems (Multiple-Input Multiple-output system을 위한 Low-Density Parity-Check codes 설계)

  • Shin, Jeong-Hwan;Chae, Hyun-Do;Han, In-Duk;Heo, Jun
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.35 no.7C
    • /
    • pp.587-593
    • /
    • 2010
  • In this paper we design an irregular low-density parity-check (LDPC) code for multiple-input multiple-output (MIMO) system, using a simple extrinsic information transfer (EXIT) chart method. The MIMO systems considered are optimal maximum a posteriori probability (MAP) detector. The MIMO detector and the LDPC decoder exchange soft information and form a turbo iterative receiver. The EXIT charts are used to obtain the edge degree distribution of the irregular LDPC code which is optimized for the MIMO detector. It is shown that the performance of the designed LDPC code is better than that of conventional LDPC code which was optimized for either the Additive White Gaussian Noise (AWGN) channel or the MIMO channel.

Improvement of Normalized CMA Channel Equalization and Turbo Code for DS-CDMA System (DS-CDMA 시스템을 위한 터보 부호와 정규화 CMA 채널 등화 개선)

  • 박노진;강철호
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.27 no.7A
    • /
    • pp.659-667
    • /
    • 2002
  • In this dissertation, in the Turbo Code used for error correction coding of the recent digital communication systems, we propose a new S-R interleaver that has the better performance than the existing block interleaver, and the Turbo Decoder that has the parallel concatenated New structure using the MAP algorithm. For real-time voice and video services over the third generation mobile communications, the performance of two proposed methods is analyzed by the reduced decoding delay using the variable decoding method by computer simulation over multipath channels of DS-CDMA system. Also, a Modified NCMA based on conventional NCMA is proposed to improve the channel efficiency in the mobile communication system, and is investigated over the multi-user environment of DS-CDMA system through computer simulation.

Bird's Eye View Semantic Segmentation based on Improved Transformer for Automatic Annotation

  • Tianjiao Liang;Weiguo Pan;Hong Bao;Xinyue Fan;Han Li
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.17 no.8
    • /
    • pp.1996-2015
    • /
    • 2023
  • High-definition (HD) maps can provide precise road information that enables an autonomous driving system to effectively navigate a vehicle. Recent research has focused on leveraging semantic segmentation to achieve automatic annotation of HD maps. However, the existing methods suffer from low recognition accuracy in automatic driving scenarios, leading to inefficient annotation processes. In this paper, we propose a novel semantic segmentation method for automatic HD map annotation. Our approach introduces a new encoder, known as the convolutional transformer hybrid encoder, to enhance the model's feature extraction capabilities. Additionally, we propose a multi-level fusion module that enables the model to aggregate different levels of detail and semantic information. Furthermore, we present a novel decoupled boundary joint decoder to improve the model's ability to handle the boundary between categories. To evaluate our method, we conducted experiments using the Bird's Eye View point cloud images dataset and Cityscapes dataset. Comparative analysis against stateof-the-art methods demonstrates that our model achieves the highest performance. Specifically, our model achieves an mIoU of 56.26%, surpassing the results of SegFormer with an mIoU of 1.47%. This innovative promises to significantly enhance the efficiency of HD map automatic annotation.

Image Compression Using Edge Map And Multi-Sided Side Match Finite-State Vector Quantization (윤곽선 맵과 다중 면 사이드 매치 유한상태 벡터 양자화를 이용한 영상 압축)

  • Cho, Seong-Hwan;Kim, Eung-Sung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.8 no.6
    • /
    • pp.1419-1427
    • /
    • 2007
  • In this paper, we propose an algorithm which implements a multi-sided side match finite-state vector quantization(MSMVQ). After extracting the edge information from an image and classifying the image into edge blocks or non-edge blocks, we construct an edge map. We subdivide edge blocks into sixteen classes using discrete cosine transform(DCT) AC coefficients. Based on edge map information, a state codebook is made from the master codebook, and side match calculation is done for two-sided or three-sided current block of image. For reducing transmitted bits, a decision is made whether or not to encode the non-edge blocks among the pre-coded blocks by using the master codebook. Also for reducing allocation bits of codeword indices to decoder, a variable length coder is used. Considering the comparison with side match finite-state vector quantization(SMVQ) and two-sided SMVQ(TSMVQ) algorithm about Zelda, Lenna, Bridge and Peppers image, the new algorithm shows better picture quality than SMVQ and TSMVQ respectively.

  • PDF

The IP development for the real-time process of SoC image protection system (SoC 영상 보안 시스템의 실시간 처리를 위한 IP 개발)

  • Jung, Kwang-Sung;Moon, Cheol-Hong
    • Proceedings of the IEEK Conference
    • /
    • 2008.06a
    • /
    • pp.605-606
    • /
    • 2008
  • The distance detection system receives stereo video input through 2 CCD cameras. Using a decoder, the image is changed to the YCbCr4:2:2 format and only the Y signal is saved in the 4*256*8bit shift register of the Dual-Port SRAM. As a result of the matching procedure, the Depth value, which is the distance information, is saved in SRAM, and the Depth Map is made and output to the TFT-LCD screen.

  • PDF

Performance Improvement of Turbo Code in low SNR and short frame sizes (낮은 SNR과 짧은 프레임에서 터보코드 성능 개선)

  • 정상연;이용식;심우성;허도근
    • Proceedings of the IEEK Conference
    • /
    • 1999.06a
    • /
    • pp.61-64
    • /
    • 1999
  • The turbo code appropriate to IMT-2000 is known to have a good performance whenever the size of frame increases. But it is not appropriate to a sort of video service to need real time because of decoding complexity and long delay time by the size of frame. Therefore this paper proposes decoding decision algorithm of short frame in which soft output is weighted according to iteration number in turbo decoder. Performance of the proposed algorithm is analysed in the AWGN channel when short length of frame is 100, 256, 640. As the result. it is appeared that the proposed decoding decision algorithm has improved in BER other than in the existing MAP decoding algorithm.

  • PDF

An image sequence coding using edge classified finite state vector quantization (윤관선 분류 유한상태 벡터 양자화를 이용한 영상 시퀀스 부호화)

  • 김응성;이근영
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.23 no.9A
    • /
    • pp.2372-2382
    • /
    • 1998
  • In this paper, we propose a new edge based finite state vector quantization method having better performance than conventional side-match finite state vector quantization. In our proposed scheme, each dCT transformed block is classified to 17 classes according to edge types. Each class has a different codebook based on its characteristis. Encoder classified each block to motion block or stationary block and constructed a merging map by using edge and motion information, and sent to decoder. We controled amoutn of bing bits transmitted with selecting modes accoridng to bandwidth of transmitting channel. Compared with conventional algorithms, H.263 and H.261 at low bit rate, our proposed algorithm shows better picture quality and good performance.

  • PDF

Distributed Coding Scheme for Multi-view Video through Efficient Side Information Generation

  • Yoo, Jihwan;Ko, Min Soo;Kwon, Soon Chul;Seo, Young-Ho;Kim, Dong-Wook;Yoo, Jisang
    • Journal of Electrical Engineering and Technology
    • /
    • v.9 no.5
    • /
    • pp.1762-1773
    • /
    • 2014
  • In this paper, a distributed image coding scheme for multi-view video through an efficient generation of side information is proposed. A distributed video coding technique corrects the errors in the side information, which is generated with the original image, by using the channel coding technique at the decoder. Therefore, the more correct the generated side information is, the better the performance of distributed video coding. The proposed technique is to apply the distributed video coding schemes to the image coding for multi-view video. It generates side information by selectively and efficiently using both 3-dimensional warping based on the depth map with spatially adjacent frames and motion-compensated temporal interpolation with temporally adjacent frames. In this scheme the difference between the adjacent frames, the sizes of the motion vectors for the adjacent blocks, and the edge information are used as the selection criteria. From the experiments, it was observed that the quality of the side information generated by the proposed technique was improved by the average peak signal-to-noise ratio of 0.97dB than the one by motion-compensated temporal interpolation or 3-dimensional warping. The result from analyzing the rate-distortion curves revealed that the proposed scheme could reduce the bit-rate by 8.01% on average at the same peak signal-to-noise ratio value, compared to previous work.