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Joint Subcarrier Time Reference Index- Modulation-Aided Differential Chaos Shift Keying Communication System

IEEE ACCESS 2024年 12卷 159935-159951页

作者： Hasan, Fadhil S. Valenzuela, Alejandro A. Mustansiriyah Univ Coll Engn Baghdad 14022 Iraq Bonn Rhein Sieg Univ Appl Sci Dept Engn & Commun D-53757 St Augustin Germany

A novel multidimensional index modulation-based differential chaos shift keying (DCSK) technique, designated as Joint Subcarrier Time Reference Index Modulation-aided Differential Chaos Shift Keying (JSTRIM-DCSK), is proposed for efficient data transmission in chaotic communication systems. The JSTRIM-DCSK system integrates subcarrier, time slot, and reference signal indexing to transmit information and offers two variants: JSTRIM-DCSK-I and JSTRIM-DCSK-II. The data is organized into L subblocks, each containing N(s )subcarrier index bits p(s) and N-t time slot index bits p(t), reference index bits p(r), and modulated bits p(m). The subcarrier and time slot index bits jointly select an active or inactive subcarrier time slot combination from a total of NsNt possibilities, categorizing the system as either JSTRIM-DCSK-I (active) or JSTRIM-DCSK-II (inactive). The reference indexed bits select a single chaotic reference signal from Nr orthogonal chaotic vectors generated using the Gram-Schmidt orthogonalization process. The modulated bits are transmitted using a DCSK modulation scheme. Analytical expressions for the bit error rate (BER) performance of the JSTRIM-DCSK system are derived under both additive white Gaussian noise (AWGN) and multipath Rayleigh fading channel (MRFC) conditions. Furthermore, the potential for energy savings, bandwidth efficiency, and system complexity of the JSTRIM-DCSK system are thoroughly analyzed and compared with those of the existing techniques. The simulation results validate the analytical expressions and demonstrate the potential of JSTRIM-DCSK to achieve high data rates, efficient energy savings, and a competitive BER performance.

关键词： Indexes Modulation Chaotic communication Vectors Bit error rate Communication systems Symbols Energy efficiency Complexity theory Generators Chaos communications modulation coding multidimensional coding multipath channels subcarrier multiplexing

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Enhanced Performance of Intensity Modulation With Direct Detection Using Golay Encoded Nyquist Pulses and Electronic Dispersion Compensation

IEEE PHOTONICS JOURNAL

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IEEE PHOTONICS JOURNAL 2024年第3期16卷 1页

作者： Barakat, Julien Moussa H. El Falou, Abdul Rahman Gurkan, Zeynep Nilhan Alboon, Shadi A. Karar, Abdullah S. Amer Univ Middle East Coll Engn & Technol Kuwait Kuwait Beirut Arab Univ BAU Dept Elect & Comp Engn Beirut 11072809 Lebanon Yarmouk Univ Hijjawi Fac Engn Technol Dept Elect Engn Irbid 21163 Jordan

The performance of intensity modulation (IM) with direct detection (DD) transmission systems is enhanced through a novel combination of multidimensional coding, Nyquist pulse shaping, and electronic dispersion compensation (EDC) at the transmitter using a finite impulse response (FIR) filter. A 24-dimensional (24D) extended Golay binary code effectively transforms each incoming 12-bit message into a 24-bit codeword, achieving a coding efficiency of 0.5 bits per symbol for a 56 Gb/s on-off keying (OOK) transmission over 80 km of single mode fiber. While this encoding process introduces a 50% overhead, the required bandwidth is maintained at 56 GHz through doubling the symbol rate and the application of Nyquist pulse shaping with a raised cosine (RC) profile and a roll-off factor of zero, resulting in a flat power spectral density. This flat distribution contrasts with standard OOK transmission at 56 Gb/s with a roll-off factor of 1.0, where signal power is predominantly concentrated in the lower frequency range. One of the key advantages of the 24D Golay code is its substantial error correction capability. However, the benefits of this multidimensional coding and Nyquist pulse shaping extend beyond error correction. It is shown that, while both the proposed and standard OOK methods exhibit comparable performance in a white Gaussian noise channel at back-to-back, they differ significantly under frequency selective power fading conditions caused by the interplay of chromatic dispersion (CD) and direct detection. The misalignment between the frequency notches introduced by the FIR pre-EDC and those inherent in the channel response, especially severe at lower frequencies, favors transmission schemes with a flat power spectral density, like the 24D Golay-coded Nyquist pulses.

关键词： multidimensional coding nyquist pulse shaping electronic dispersion compensation intensity modulation direct detection transmission finite impulse response filter

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A Complete Video coding Chain Based on Multi-Dimensional Discrete Cosine Transform

A Complete Video Coding Chain Based on Multi-Dimensional Dis...

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作者： Fryza, T. Brno University of Technology

The paper deals with a video compression method based on the multi-dimensional discrete cosine transform. In the text, the encoder and decoder architectures including the deﬁnitions of all mathematical operations like the forward and inverse 3-D DCT, quantization and thresholding are presented. According to the particular number of currently processed pictures, the new quantization tables and entropy code dictionaries are proposed in the paper. The practical properties of the 3-D DCT coding chain compared with the modern video compression methods (such as H.264 and WebM) and the computing complexity are presented as well. It will be proved the best compress properties could be achieved by complex H.264 codec. On the other hand the computing complexity - especially on the encoding side - is lower for the 3-D DCT method.

关键词： Video signal processing data compression discrete cosine transform multidimensional coding digital signal processors.

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Extending the CCSDS Recommendation for Image Data Compression for Remote Sensing Scenarios

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IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 2009年第10期47卷 3431-3445页

作者： Garcia-Vilchez, Fernando Serra-Sagrista, Joan Univ Autonoma Barcelona Dept Informat & Commun Engn Barcelona 08290 Spain

This paper presents prominent extensions that have been proposed for the Consultative Committee for Space Data Systems Recommendation for Image Data Compression (CCSDS122-B-1). Thanks to the proposed extensions, the Recommendation gains several important featured advantages: It allows any number of spatial wavelet decomposition levels;it provides scalability by quality, position, resolution, and component;and it supports multi-/hyper-/ultraspectral data coding, allowing a spectral decorrelation if requested. As a consequence, compression performance is notably improved with respect to the Recommendation for a large variety of remote sensing images, both monoband and multi-/hyper-/ultraspectral images. Reported results for hyperspectral data suggest that our proposal is competitive with the JPEG2000 standard.

关键词： Data compression image coding multidimensional coding standards

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Disparity compensated view filtering wavelet based multiview image codec using Lagrangian optimization

Disparity compensated view filtering wavelet based multiview...

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3DTV Conference - True Vision - Capture, Transmission and Display of 3D Video

作者： Akbari, Akbar Sheikh Canagarajah, Nishan Redmill, David Bull, David Univ Bristol Dept Elect & Elect Engn Bristol BS8 1UB Avon England

ISBN: (纸本)9781424417605

This paper presents a disparity compensated view filtering wavelet based multiview image coding scheme. The proposed codec decorrelates the input views into their frequency subbands using a disparity compensated lifting based wavelet transform. The codec then applies a 2D wavelet transform on baseband-image transforming it into a number of subbands. The general form of the Lagrangian rate distortion optimization algorithm is then modified and used along with the steepest descent algorithm to assign bits among the different subbands in such a way that it minimizes the PSNR variance of the decoded images. Two sets of experimental results are generated using three sets of multiview test images. In the first set of experiments the effect of using a weighted X for high frequency images on the PSNR variance of the decoded images is investigated. In the second set of experiments, performance of the proposed codec in reducing the variance of the PSNR of the decoded images is investigated. Results indicate that the proposed codec gives lower PSNR variance among the decoded images compared to the basic form of the codec at all bitrates.

关键词： image codecs multidimensional coding stereo vision

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A novel H.264/AVC based multi-view video coding scheme

A novel H.264/AVC based multi-view video coding scheme

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1st International Conference on 3DTV

作者： Akbari, Akbar Sheikh Canagarajah, Nishan Redmill, David Bull, Dave Agrafiotis, Dimitris Univ Bristol Dept Elect & Elect Engn Bristol BS8 1UB Avon England

ISBN: (纸本)9781424407217

This paper investigates extensions of H.264/AVC for compressing multi-view video sequences. The proposed technique re-sorts frames of sequences captured by multiple cameras looking at a person in a scene from different views and generates a single video sequence. The multi-frame referencing property of the H.264/AVC, which enables exploitation of the spatial and temporal redundancy contained in the multi-view sequences, is employed to implement several modes of operation in the proposed coding algorithm. To evaluate the performance of the proposed coding technique at different modes of operations, five multi-view video sequences at different frame rates were coded using the proposed and the simulcast H.264/AVC coding schemes. Experiments show the superior performance of the proposed coding scheme when coding the multi-view sequences at low and up to half of the original frame rates.

关键词： video codecs multidimensional coding stereo vision

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Rate distortion optimal bit allocation methods for volumetric data using JPEG 2000

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2006年第8期15卷 2106-2112页

作者： Kosheleva, Olga M. Usevitch, Bryan E. Cabrera, Sergio D. Vidal, Edward, Jr. Univ Texas Dept Elect & Comp Engn El Paso TX 79968 USA USA Res Lab White Sands Missile Range NM 88002 USA

Computer modeling programs that generate three-dimensional (3-D) data on fine grids are capable of generating very large amounts of information. These data sets, as well as 3-D sensor/measured data sets, are prime candidates for the application of data compression algorithms. A very flexible and powerful compression algorithm for imagery data is the newly released JPEG 2000 standard. JPEG 2000 also has the capability to compress volumetric data, as described in Part 2 of the standard, by treating the 3-D data as separate slices. As a decoder standard, JPEG 2000 does not describe any specific method to allocate bits among the separate slices. This paper proposes two new bit allocation algorithms for accomplishing this task. The first procedure is rate distortion optimal (for mean squared error), and is conceptually similar to postcompression rate distortion optimization used for coding codeblocks within JPEG 2000. The disadvantage of this approach is its high computational complexity. The second bit allocation algorithm, here called the mixed model (MM) approach, mathematically models each slice's rate distortion curve using two distinct regions to get more accurate modeling at low bit rates. These two bit allocation algorithms are applied to a 3-D Meteorological data set. Test results show that the MM approach gives distortion results that are nearly identical to the optimal approach, while significantly reducing computational complexity.

关键词： bit-rate allocation data compression image coding JPEG2000 multidimensional coding rate distortion theory

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A multi-view video codec based on H.264

A multi-view video codec based on H.264

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IEEE International Conference on Image Processing (ICIP 2006)

作者： Bilen, Cagdas Aksay, Anil Akar, Gozde Bozdagi Middle E Tech Univ Dept Elect & Elect Engn TR-06531 Ankara Turkey

ISBN: (纸本)9781424404810

H.264 is the current state-of-the-art monoscopic video codec providing almost twice the coding efficiency with the same quality comparing the previous codecs. With the increasing interest in 3D TV, multi-view video sequences that are provided by multiple cameras capturing the three dimensional objects and/or scene are more widely used. Compressing multi-view sequences independently with H.264 (simulcast) is not efficient since the redundancy between the closer cameras is not exploited. In order to reduce these redundancies, we propose a Multi-View Video Codec based on H.264 using disparity estimation/compensation as well as motion estimation/compensation. In order to effectively search for disparity/motion without increasing computational complexity, we modified the buffering structure of H.264 and implemented several referencing modes. Our results show that for closely located cameras, our codec outperforms simulcast H.264 coding. For sparsely located cameras, our method can still improve coding gain depending on the video characteristics.

关键词： video coding multidimensional coding stereo vision

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Rate-distortion optimization in dynamic mesh compression

Rate-distortion optimization in dynamic mesh compression

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IEEE International Conference on Image Processing (ICIP 2006)

作者： Mueller, K. Smolic, A. Kautzner, M. Wiegand, T. Heinrich Hertz Inst Nachrichtentech Berlin GmbH Fraunhofer Inst Telecommun Image Proc Dept Einsteinufer 37 D-10587 Berlin Germany

ISBN: (纸本)9781424404810

Recent developments in the compression of dynamic meshes or mesh sequences have shown that the statistical dependencies within a mesh sequence can be exploited well by predictive coding approaches. Coders introduced so far use experimentally determined or heuristic thresholds for tuning the algorithms. In video coding rate-distortion (RD) optimization is often used to avoid fixing of thresholds and to select a coding mode. We applied these ideas and present here an RD-optimized mesh coder. It includes different prediction modes as well as an RD cost computation that controls the mode selection across all possible spatial partitions of a mesh to find the clustering structure together with the associated prediction modes. The structure of the RD-optimized D3DMC coder is presented, followed by comparative results with mesh sequences at different resolutions.

关键词： linear predictive coding multidimensional coding 3D compression rate-distortion optimization

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Multichip differential phase encoded optical transmission

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IEEE PHOTONICS TECHNOLOGY LETTERS 2005年第5期17卷 1133-1135页

作者： Nazarathy, M Simony, E Technion Israel Inst Technol Dept Elect Engn IL-32000 Haifa Israel

We introduce a new multichip differential phase-shift keying (MC-DPSK) family of advanced optical modulation formats, whereby differential phase encoding is simultaneously applied to multiple (> 2) consecutive time slots (chips). Four-chip quaternary phase MC-DPSK attains the same spectral efficiency (SE) as differential quaternary phase-shift keying while improving the quantum limit sensitivity by 1.4 dB [22.4 versus 31 photons per bit at 10(-9) bit-error rate (BER)]. A novel coded version of four-chip four-phase MC-DPSK using 16 codewords forming a maximally unbiased base attains 33% better SE than differential binary phase-shift keying, reaching the lowest quantum limit sensitivity to date (14.6 versus 20 photons per bit at 10(-9) BER).

关键词： differential phase-shift keying (DPSK) integrated optics (IO) maximum likelihood (ML) decoding multidimensional coding optical fiber communication phase modulation

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