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IEEE TRANSACTIONS ON NANOBIOSCIENCE 2023年第1期22卷 78-91页

作者： Yu, Jingxiang Li, Hui Univ Sci & Technol China CAS Key Lab Wireless Opt Commun Hefei 230026 Peoples R China

Molecular communication (MC), which transmits information through molecules, has emerged as a promising technique to enable communication links between nanomachines. To establish information transmission using molecules, synthetic biology through genetic circuits techniques can be utilized to construct biological components. Recent efforts on genetic circuits have produced many exciting MC systems and generated substantial insights. With basic gene regulatory modules and motifs, researchers are now constructing artificial networks with novel functions that will serve as building blocks in the MC system. In this paper, we investigate the design of genetic circuits to implement the convolutional codec in a diffusion-based MC channel with the concentration shift keying (CSK) transmission scheme. At the receiver, a majority-logic decoder is applied to decode the received symbols. These functions are completely realized in the field of biochemistry through the activation and inhibition of genes and biochemical reactions, rather than through classical electrical circuits. Biochemical simulations are used to verify the feasibility of the system and analyze the impairments caused by diffusion noise and chemical reaction noise of genetic circuits.

关键词： Genetics convolutional codes Decoding Nanobioscience Biological information theory Modulation Proteins Molecular communication genetic circuits convolutional coding majority-logic decoding

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Adaptive Channel coding to Enhance the Performance in Rayleigh Channel

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INTERNATIONAL JOURNAL OF ADVANCED COMPUTER SCIENCE AND APPLICATIONS 2024年第6期15卷 504-511页

作者： Srividya, L. Sudha, P. N. Dayananda Sagar Coll Engn Dept Elect & Commun Engn Bangalore India KS Inst Technol Dept Elect & Commun Engn Bangalore India

Rayleigh fading channel model is usually used to model real time wireless mobile communication as it has the potential to emulate the multipath scattering effect, dispersion, fading, reflection, refraction and Doppler shift. Mobility and interferences, will change the channel conditions over the time and so will the error environment and results in variable bit error rates (BER). Fixed channel coding schemes have proven in providing reliability of the data despite of poor channel conditions, but fails to contend with time varying channel conditions. Hence they suffer loss in the information rate during good channel conditions. There is need for adaptive scheme that adapts dynamically to channel conditions improving the overall performance and reliability in communication. An adaptive channel coding technique(ACC) is proposed in this paper which requires a simple statistics from the receiver and switches two channel coding schemes dynamically to the changing environment and makes it different from other schemes which deals dynamic tuning of parameters of one Error control coding (ECC) scheme. This strategy not only guarantees reliability but also spectral efficiency as channel capacity is utilized effectively by switching between two ECCs, less robust (high data rate) convolutional ECC is used when the channel conditions are good and more robust (low data rate) Turbo ECC is used when the channel conditions degraded. Proposed concept is implemented using MATLAB and results outperforms the conventional fixed ECC schemes, an effective reduction of Eb/N0 requirement is obtained for a target BER compared to the fixed or predetermined ECCs. ACC is tested under various mobile channel environment and proven resilient to varying channel conditions. It is beneficial in providing flexibility in QoS by changing the switching criteria according to the application.

关键词： Adaptive error control coding turbo coding convolutional coding bit error rate throughput Rayleigh channel

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Sparse deep predictive coding captures contour integration capabilities of the early visual system

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PLOS COMPUTATIONAL BIOLOGY 2021年第1期17卷 e1008629-e1008629页

作者： Boutin, Victor Franciosini, Angelo Chavane, Frederic Ruffier, Franck Perrinet, Laurent Aix Marseille Univ Inst Neurosci Timone CNRS Marseille France Aix Marseille Univ CNRS ISM Marseille France

Both neurophysiological and psychophysical experiments have pointed out the crucial role of recurrent and feedback connections to process context-dependent information in the early visual cortex. While numerous models have accounted for feedback effects at either neural or representational level, none of them were able to bind those two levels of analysis. Is it possible to describe feedback effects at both levels using the same model? We answer this question by combining Predictive coding (PC) and Sparse coding (SC) into a hierarchical and convolutional framework applied to realistic problems. In the Sparse Deep Predictive coding (SDPC) model, the SC component models the internal recurrent processing within each layer, and the PC component describes the interactions between layers using feedforward and feedback connections. Here, we train a 2-layered SDPC on two different databases of images, and we interpret it as a model of the early visual system (V1 & V2). We first demonstrate that once the training has converged, SDPC exhibits oriented and localized receptive fields in V1 and more complex features in V2. Second, we analyze the effects of feedback on the neural organization beyond the classical receptive field of V1 neurons using interaction maps. These maps are similar to association fields and reflect the Gestalt principle of good continuation. We demonstrate that feedback signals reorganize interaction maps and modulate neural activity to promote contour integration. Third, we demonstrate at the representational level that the SDPC feedback connections are able to overcome noise in input images. Therefore, the SDPC captures the association field principle at the neural level which results in a better reconstruction of blurred images at the representational level. Author summary One often compares biological vision to a camera-like system where an image would be processed according to a sequence of successive transformations. In particular, this "feedforward"

关键词： Neurons coding mechanisms Vision Visual cortex Neurophysiology convolutional coding Sensory perception Visual system

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convolutional Sparse and Low-Rank coding-Based Image Decomposition

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2018年第5期27卷 2121-2133页

作者： Zhang, He Patel, Vishal M. Rutgers Univ New Brunswick Dept Elect & Comp Engn New Brunswick NJ 08901 USA

We propose novel convolutional sparse and low-rank coding-based methods for cartoon and texture decomposition. In our method, we first learn a set of generic filters that can efficiently represent cartoon-and texture-type images. Then, using these learned filters, we propose two optimization frameworks to decompose a given image into cartoon and texture components: convolutional sparse coding-based image decomposition;and convolutional low-rank coding-based image decomposition. By working directly on the whole image, the proposed image separation algorithms do not need to divide the image into overlapping patches for leaning local dictionaries. The shift-invariance property is directly modeled into the objective function for learning filters. Extensive experiments show that the proposed methods perform favorably compared with state-of-theart image separation methods.

关键词： Image decomposition convolutional coding low-rank coding sparse coding

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Impact of code rate and constraint length variation on qualitative performance of OIDMA system with random inter-leaver

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OPTIK 2020年 202卷

作者： Maurya, Ajay Kumar Prakash, Ravi Sriwas, S. K. Kumar, Pramod Singh, R. K. Veer Bahadur Singh Purvanchal Univ Jaunpur UNS Inst Engn & Technol Dept Elect & Instrumentat Engn Jaunpur Uttar Predesh India Veer Bahadur Singh Purvanchal Univ UNS Inst Engn & Technol Dept Elect & Commun Engn Jaunpur 222003 Uttar Pradesh India Bundelkhand Inst Engn & Technol Dept Elect & Commun Engn Jhansi 284128 Uttar Pradesh India Manipal Acad Higher Educ Manipal Inst Technol Dept Elect & Commun Engn Manipal 576104 Karnataka India Kamla Nehru Inst Technol Sultanpur Dept Elect Engn Sultanpur 228118 Uttar Pradesh India

The impact of the code rate and constraint length on the qualitative performance of optical interleave division multiple access (OIDMA) system is analyzed. The various topologies of convolution encoder design have implemented by considering various shift registers as well as several Ex-OR gates to achieve the performance. Further, the bit error rate (BER) calculated for a different possible combination of random inter-leaver. The BER increases with the number of users, whereas it decreases with the code rate and constraint length.

关键词： OIDMA convolutional coding Network topology Random inter-leaver Constraint length

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New mobile communication system design for Rayleigh environments based on compressed sensing-source coding

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IET COMMUNICATIONS 2019年第15期13卷 2375-2385页

作者： Haneche, Houria Ouahabi, Abdeldjalil Boudraa, Bachir USTHB LCPTS BP 32 El Alia Algiers 16111 Algeria Polytech Tours INSERM U930 Imaging & Brain 7 Ave Marcel Dassault F-37200 Tours France Bouira Univ Comp Sci Dept LIMPAF Bouira Algeria

A new end-to-end communication system is proposed to increase transmission speed, robustness, and security in order to meet the requirements of mobile systems that know an exponentially increasing data amount over time. The design relies on the use of compressed sensing-source coding instead of the supported speech coding standards in actual mobile communication systems. The proposed compressed sensing-source coding method allows reducing the speech coding complexity by using simple quantisation and binary encoding, saving communication system resources, and encrypting communications without additional costs. The performance of the resulting communication system is evaluated for speech communication via 10 dB Rayleigh environment in terms of perceptual evaluation of speech quality (PESQ) scores and coherence speech intelligibility index (CSII) when convolutional coding, orthogonal frequency division multiplexing, and diversity schemes are used. Results report that for a bit rate of 12.8 kbit/s the proposed scheme achieves fair speech intelligibility justified by a CSII value of 0.5, and offers good output speech quality measure, providing a PESQ of 3.33 for the same bit rate.

关键词： noise figure 10.0 dB source coding speech intelligibility compressed sensing-source coding method good output speech quality measure bit rate 12.8 kbit/s convolutional codes speech quality scores speech coding exponentially increasing data amount supported speech 10 dB Rayleigh environment speech coding complexity mobile systems communication system resources fair speech intelligibility Rayleigh channels end-to-end communication system encrypting communications actual mobile communication systems new mobile communication system design Rayleigh environments speech intelligibility index convolutional coding OFDM modulation speech communication resulting communication system speech enhancement

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Investigation of the Performance of Single Carrier Visible Light Communication Systems in Multi-Path Fading Optical Channels 28

Investigation of the Performance of Single Carrier Visible L...

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28th Signal Processing and Communications Applications Conference (SIU)

作者： Yasar, Sabiha Sinop, Hayriye Tek, Yusuf Islam Tuna, Elif Busra Karaerik, Kudret Ozen, Ali Nuh Naci Yazgan Univ Elekt Elekt Muhendisligi BOlumu HARGEM Kayseri Turkey

ISBN: (纸本)9781728172064

In this paper, the performances of single carrier visible light communication systems are analyzed in multi-path fading optical channels. Distortions in the data sent due to the multipath optical channel are corrected by linear and nonlinear channel equalizers. Computer simulations are performed to compare the equalizers with each other and to obtain the uncoded and encoded bit error rate performances. As a result of the simulation results, it was observed that the convolutional coded and Turbo coded system eliminates the error floor at each iteration.

关键词： visible light communication multipath optical channel channel equalizer convolutional coding Turbo coding

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On the Use of NB-IoT over GEO Satellite Systems with Time-Packed Optical Feeder Links for Over-the-Air Firmware/Software Updates of Machine-Type Terminals

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SENSORS 2021年第12期21卷 3952-3952页

作者： Bas, Joan Dowhuszko, Alexis A. Ctr Tecnol Telecomunicac Catalunya CTTC CERCA Dept Array & Multisensor Proc Av Karl Friedriech Gauss 7Bldg B4 Castelldefels 08860 Spain Aalto Univ Dept Commun & Networking Espoo 02150 Finland

The verticals of 5G, such as the automotive, smart grid, and smart cities sectors, will bring new sensors and IoT devices requiring Internet connectivity. Most of these machine-type terminals will be sparsely distributed, covering a very large geographical area and, from time to time, will have to update their software, firmware, and/or other relevant data. Given this situation, one viable solution to implement the "Over-the-Air" update of these IoT terminals can be done with the aid of GEO satellite systems. However, due to the ultra-dense radio frequency reuse factor that contemporary High-Throughput Satellite (HTS) systems implement in the access link to serve the IoT terminals, the use of a time-packed Free Space Optical (FSO) link represents a practical solution to avoid the bottleneck that the satellite gateway experiences in the feeder link. The performance of both Detect-and-Forward and Decode-and-Forward relaying strategies are studied, assuming that the single-carrier M-PAM symbols that are transmitted on the optical feeder link are mapped into M-QAM symbols that modulate the multiple sub-carriers of the OFDM-based radio access link. In addition, the benefits of encapsulating the NB-IoT frames into DVB-S2(X) satellite frames is also analyzed in detail. The effects of the impairments introduced in both the optical feeder and radio access links are characterized in detail, and the end-to-end error correction capabilities of the Modulation and coding Schemes (MCS) defined in the contemporary releases of the NB-IoT and DVB-S2(X) standards are studied for different working regimes.

关键词： NB-IoT DVB-S2(X) high-throughput satellite optical feeder link over-the-air updates time-packing decode-and-forward scintillation beam-wander convolutional coding

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Complexity and diversity in sparse code priors improve receptive field characterization of Macaque V1 neurons

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PLOS COMPUTATIONAL BIOLOGY 2021年第10期17卷 e1009528-e1009528页

作者： Wu, Ziniu Rockwell, Harold Zhang, Yimeng Tang, Shiming Lee, Tai Sing Carnegie Mellon Univ Ctr Neural Basis Cognit Pittsburgh PA 15213 USA Carnegie Mellon Univ Neurosci Inst Pittsburgh PA 15213 USA Carnegie Mellon Univ Dept Math Pittsburgh PA 15213 USA Carnegie Mellon Univ Dept Biol Sci Pittsburgh PA 15213 USA Carnegie Mellon Univ Comp Sci Dept Pittsburgh PA 15213 USA Peking Univ Ctr Life Sci Beijing Peoples R China MIT Dept EECS 77 Massachusetts Ave Cambridge MA 02139 USA Univ Chicago Comm Computat Neurosci Chicago IL 60637 USA

System identification techniques-projection pursuit regression models (PPRs) and convolutional neural networks (CNNs)-provide state-of-the-art performance in predicting visual cortical neurons' responses to arbitrary input stimuli. However, the constituent kernels recovered by these methods are often noisy and lack coherent structure, making it difficult to understand the underlying component features of a neuron's receptive field. In this paper, we show that using a dictionary of diverse kernels with complex shapes learned from natural scenes based on efficient coding theory, as the front-end for PPRs and CNNs can improve their performance in neuronal response prediction as well as algorithmic data efficiency and convergence speed. Extensive experimental results also indicate that these sparse-code kernels provide important information on the component features of a neuron's receptive field. In addition, we find that models with the complex-shaped sparse code front-end are significantly better than models with a standard orientation-selective Gabor filter front-end for modeling V1 neurons that have been found to exhibit complex pattern selectivity. We show that the relative performance difference due to these two front-ends can be used to produce a sensitive metric for detecting complex selectivity in V1 neurons.

关键词： Neurons Convolution Neuronal tuning Monkeys coding mechanisms Kernel methods Vision convolutional coding

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Experimental study on repeater-free acoustic telemetry for downhole operations

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JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING 2021年 202卷 108551-108551页

作者： Pagtalunan, Jed Parmar, Kaushik Kim, Seonghwan Moon, Bryan Park, Simon S. Univ Calgary Schulich Sch Engn Dept Mech & Mfg Engn Calgary AB Canada MKS Investments Ltd 736-6 Ave SW Calgary AB Canada

Measurement while drilling (MWD) enables real-time measurement of downhole conditions for directional drilling, but most commercial MWD telemetry techniques suffer from limited transmission speeds. Acoustic telemetry has the potential for significantly faster transmission speeds, but it has limited range due to drill string attenuation and noise. A common solution to this is to use acoustic repeaters, which incur high costs and require complex implementation. Instead of using repeaters, we utilized two carrier frequencies at the modes to transmit redundant data in combination with a lock-in amplifier (LIA) to extract the signals from the carriers. The extracted signals were then fused at the receiver to increase signal fidelity. An experimental setup was developed to transmit acoustic signals through a simulated drill string. The signals were first attenuated by the rubber section of the simulated drill string. The results show that the proposed system was able to achieve error-free transmission of packets at 64 bps up to 1.95 km without the use of a repeater which is orders of magnitude faster than current commercial MWD methods (mud-pulse and electromagnetic).

关键词： Acoustic telemetry Downhole drilling convolutional coding Lock-in amplifier

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