Journal articles: 'Multiple Active Spatial Modulation'

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Anto., Nicy. "MULTIPLE ACTIVE SPATIAL MODULATION IN MIMO SYSTEMS." International Journal of Advanced Research 4, no. 9 (September 30, 2016): 547–51. http://dx.doi.org/10.21474/ijar01/1516.

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Solanki, KS, and Abhilasha Singh. "MULTIPLE ACTIVE SPATIAL MODULATION IN MIMO SYSTEMS." International Journal of Advanced Research 5, no. 9 (September 30, 2017): 391–93. http://dx.doi.org/10.21474/ijar01/5340.

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v. Nair, Karthika, and Poorna R. Prabhu. "Multiple Active Spatial Modulation in MIMO Systems." International Journal of Engineering Trends and Technology 10, no. 10 (April 25, 2014): 489–91. http://dx.doi.org/10.14445/22315381/ijett-v10p295.

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Irfan, Mohammad, and Sonia Aissa. "Multiple Active Spatial Modulation: A Possibility of More Than Spatial Multiplexing." IEEE Wireless Communications Letters 9, no. 3 (March 2020): 294–97. http://dx.doi.org/10.1109/lwc.2019.2953028.

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Iqbal, Zahid, Fei Ji, and Yun Liu. "Virtual Spatial Channel Number and Index Modulation." Wireless Communications and Mobile Computing 2021 (September 11, 2021): 1–10. http://dx.doi.org/10.1155/2021/2982226.

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This paper proposes a novel precoding-aided and efficient data transmission scheme called virtual spatial channel number and index modulation (VS-CNIM), which conveys extra data by changing both the number and index of active virtual parallel channels of multiple-input multiple-output (MIMO) channels, obtained through the singular value decomposition (SVD) in each time slot. Unlike the conventional virtual spatial modulation (VSM), where extra data bits are transmitted only using index of active virtual parallel channels, the VS-CNIM scheme, depending on incoming information bits, transmits extra bits utilizing both the number and indices of active parallel channels along the bits carried by M -ary constellation symbols. Therefore, VS-CNIM provides significantly superior spectral efficiency (SE) compared to VSM. Considering the influence of imperfect channel estimation, a closed-form upper bound is derived on average bit error probability (ABEP). The asymptotic performance is also analyzed, which gives the coding gain and diversity order and describes error floor under the consideration of perfect and imperfect channel estimation, respectively. Monte Carlo simulations exhibit that the VS-CNIM scheme achieves considerably better error performance and high SE than precoding-aided SM (PSM) and VSM schemes.

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Abdulhamid, Mohanad, and Mwaniki Muchai. "Performance of Multiple Rank Modulation Based on SM-MIMO." Land Forces Academy Review 24, no. 1 (March 1, 2019): 61–67. http://dx.doi.org/10.2478/raft-2019-0007.

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Abstract A multiple rank modulation (MRM) scheme is proposed that provides better error performance, enhances the data rate and reduces the system demodulation complexity. Multiple input multiple output (MIMO) scheme is a technique that uses several antennas at the transmitter and receiver to minimize error and optimize data speed. MRM is a novel technique that borrows from spatial modulation-MIMO (SM-MIMO) scheme. The basic idea of this scheme involves the transmitter receiving a group of bits and subdividing them into two blocks; rank index block and signal modulation block. The rank index bit block is used to select the rank to be activated and the rank selected contains at least one active transmit antenna (TA). The signal modulation bit block is encoded in a given modulation scheme for transmission. It is then transmitted through the activated rank that contains at least one active TA. The transmitted encoded signal modulation bit block is received through the receive antenna and a receiver. The receiver estimates a rank index and the transmitted symbol from the signal received. The signal modulation bit block is finally decoded. This paper addresses the performance of MRM scheme based on error performance to run cellular fifth generation (5G). We perform and present simulation results of MIMO systems employing MRM scheme to generate bit error rate (BER) of this system.

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Murtala, Sheriff, Tasnim Holoubi, Nishal Muchena, Manar Mohaisen, and Kang-Sun Choi. "On the Performance of the Multiple Active Antenna Spatial Modulation with 3-Dimensional Constellation." Applied Sciences 10, no. 11 (May 27, 2020): 3718. http://dx.doi.org/10.3390/app10113718.

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In spatial modulation (SM), a single signal symbol is transmitted from a given physical antenna, where both the signal symbol and the antenna index carry information. SM with multiple active antennas (MA-SM) transmits several signal symbols from a combination of antennas at each channel use, thereby increasing the spectral efficiency. MA-SM is proposed in combination with a new 3-dimensional constellation, where signal symbols transmitted from a given antenna combination are rotated before transmission. In this paper, we derived an upper-bound on the error probability of the MA-SM as a function of the rotation angles. The search for the optimal rotation angles is modeled as a multi-objective optimization problem. We concluded based on both analytical and simulation results that the 3-dimensional constellation with the optimal angles achieved negligible improvement. Therefore, we do not recommend using the 3-dimensional constellation with the MA-SM system.

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Akuon, Peter Odero, and Hongjun Xu. "Performance of multiple active-spatial modulation: information theoretic criteria over correlated Rayleigh fading channels." IET Communications 10, no. 9 (June 9, 2016): 1071–79. http://dx.doi.org/10.1049/iet-com.2015.0822.

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Wang, Jintao, Shuyun Jia, and Jian Song. "Generalised Spatial Modulation System with Multiple Active Transmit Antennas and Low Complexity Detection Scheme." IEEE Transactions on Wireless Communications 11, no. 4 (April 2012): 1605–15. http://dx.doi.org/10.1109/twc.2012.030512.111635.

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Junejo, Naveed Ur Rehman, Hamada Esmaiel, Haixin Sun, Zeyad A. H. Qasem, and Junfeng Wang. "Pilot-Based Adaptive Channel Estimation for Underwater Spatial Modulation Technologies." Symmetry 11, no. 5 (May 24, 2019): 711. http://dx.doi.org/10.3390/sym11050711.

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Spatial Modulation Technologies (SMTs) are schemes that reduce inter-carrier interference (ICI), inter-channel interference, inter-antenna synchronization (IAS), and system complexity for multiple-input multiple-output (MIMO) communication systems. Moreover, high spectral and energy efficiency have rendered SMTs attractive to underwater acoustic (UWA) MIMO communication systems. Consequently, this paper focuses on SMTs such as spatial modulation (SM), generalized spatial modulation (GSM), and fully generalized spatial modulation (FGSM) in which one constant number and one multiple number of antennas are active to transmit data symbols in any time interval for underwater acoustic communication (UWAC). In SMTs, the receiver requires perfect channel state information (P-CSI) for accurate data detection. However, it is impractical that the perfect channel knowledge is available at the receiver. Therefore, channel estimation is of critical importance to obtain the CSI. This paper proposes the pilot-based recursive least-square (RLS) adaptive channel estimation method over the underwater time-varying MIMO channel. Furthermore, maximum likelihood (ML) decoder is used to detect the transmitted data and antennas indices from the received signal and the estimated UWA-MIMO channel. The numerical computation of mean square error (MSE) and bit error rate (BER) performance are computed for different SMTs like SM, GSM and FSGM using Monte Carlo iterations. Simulation results demonstrate that the RLS channel estimation method achieves the nearly same BER performance as P-CSI.

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Qasem, Zeyad A. H., Hamada Esmaiel, Haixin Sun, Junfeng Wang, Yongchun Miao, and Sheraz Anwar. "Enhanced Fully Generalized Spatial Modulation for the Internet of Underwater Things." Sensors 19, no. 7 (March 28, 2019): 1519. http://dx.doi.org/10.3390/s19071519.

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A full design of the Internet of Underwater Things (IoUT) with a high data rate is one of the greatest underwater communication difficulties due to the unavailability of a sustainable power source for the battery supplies of sensor nodes, electromagnetic spread weakness, and limited acoustic waves channel bandwidth. This paper presents a new energy-efficient communication scheme named Enhanced Fully Generalized Spatial Modulation (EFGSM) for the underwater acoustic channel, where the different number of active antennas used in Fully Generalized Spatial Modulation (FGSM) is combined with multiple signal constellations. The proposed EFGSM enhances energy efficiency over conventional schemes such as spatial modulation, generalized spatial modulation, and FGSM. In order to increase energy and spectral performance, the proposed technique conveys data bits not just by the number of active antenna's index as in the existing traditional FGSM, but also using the type of signal constellation to increase the data bit rate and improve power saving without increasing the receiver’s complexity. The proposed EFGSM uses primary and secondary constellations as indexes to carry information, they are derived from others by geometric interpolation signal space. The performance of the suggested EFGSM is estimated and demonstrated through Monte Carlo simulation over an underwater acoustic channel. The simulation results confirm the advantage of the suggested EFGSM scheme not just regarding energy and spectral efficiency but also concerning the average bit error rate (ABER).

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Jing, Xiaorong, Mingyue Wang, Wei Zhou, and Hongqing Liu. "Improved QRD-M Detection Algorithm for Generalized Spatial Modulation Scheme." International Journal of Antennas and Propagation 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/3581592.

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Generalized spatial modulation (GSM) is a spectral and energy efficient multiple-input multiple-output (MIMO) transmission scheme. It will lead to imperfect detection performance with relatively high computational complexity by directly applying the original QR-decomposition with M algorithm (QRD-M) to the GSM scheme. In this paper an improved QRD-M algorithm is proposed for GSM signal detection, which achieves near-optimal performance but with relatively low complexity. Based on the QRD, the improved algorithm firstly transforms the maximum likelihood (ML) detection of the GSM signals into searching an inverted tree structure. Then, in the searching process of the M branches, the branches corresponding to the illegitimate transmit antenna combinations (TACs) and related to invalid number of active antennas are cut in order to improve the validity of the resultant branches at each level by taking advantage of characteristics of GSM signals. Simulation results show that the improved QRD-M detection algorithm provides similar performance to maximum likelihood (ML) with the reduced computational complexity compared to the original QRD-M algorithm, and the optimal value of parameter M of the improved QRD-M algorithm for detection of the GSM scheme is equal to modulation order plus one.

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Park, Chang, Gyeong Kim, Suck Hong, Hwi Lee, and Chang-Seok Kim. "Quasi-Distributed Active-Mode-Locking Laser Interrogation with Multiple Partially Reflecting Segment Sensors." Sensors 18, no. 12 (November 25, 2018): 4128. http://dx.doi.org/10.3390/s18124128.

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A new type of quasi-distributed sensor system is implemented using an active mode locking (AML) laser cavity with multiple partially reflecting segments. The mode locking frequency of the AML laser is linearly proportional to the overall lasing cavity length. To implement multiple resonators having multiple reflection points installed in a sensing fiber, two types of partial reflectors (PRs) are implemented for an in-line configuration, one with fiber Bragg grating and the other with a fiber Fabry–Perot interferometer. Since the laser has oscillated only when the modulation frequencies for the mode locking frequency match with the corresponding resonator lengths, it is possible to read the multiple partially reflecting segments along the sensing fiber. The difference between two corresponding mode locking frequencies is changing proportionally with the segment length variation between two PRs upon strain application. The segment length change caused by the applied strain can be successfully measured with a linear sensitivity between mode locking frequency and displacement, linearity over 0.99, and spatial position resolution below meter order.

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Zhang, Xinhe, Wenbo Lv, and Haoran Tan. "Low-Complexity GSM Detection Based on Maximum Ratio Combining." Future Internet 14, no. 5 (May 23, 2022): 159. http://dx.doi.org/10.3390/fi14050159.

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Generalized spatial modulation (GSM) technology is an extension of spatial modulation (SM) technology, and one of its main advantages is to further improve band efficiency. However, the multiple active antennas for transmission also brings the demodulation difficulties at the receiver. To solve the problem of high computational complexity of the optimal maximum likelihood (ML) detection, two sub-optimal detection algorithms are proposed through reducing the number of transmit antenna combinations (TACs) detected at the receiver. One is the maximum ratio combining detection algorithm based on repetitive sorting strategy, termed as (MRC-RS), which uses MRC repetitive sorting strategy to select the most likely TACs in detection. The other is the maximum ratio combining detection algorithm, which is based on the iterative idea of the orthogonal matching pursuit, termed the MRC-MP algorithm. The MRC-MP algorithm reduces the number of TACs through finite iterations to reduce the computational complexity. For M-QAM constellation, a hard-limited maximum likelihood (HLML) detection algorithm is introduced to calculate the modulation symbol. For the M-PSK constellation, a low-complexity maximum likelihood (LCML) algorithm is introduced to calculate the modulation symbol. The computational complexity of these two algorithms for calculating the modulation symbol are independent of modulation order. The simulation results show that for GSM systems with a large number of TACs, the proposed two algorithms not only achieve almost the same bit error rate (BER) performance as the ML algorithm, but also can greatly reduce the computational complexity.

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Song, Tingting, Ampalavanapillai Nirmalathas, and Christina Lim. "Demonstration of Spatial Modulation Using a Novel Active Transmitter Detection Scheme with Signal Space Diversity in Optical Wireless Communications." Sensors 22, no. 22 (November 21, 2022): 9014. http://dx.doi.org/10.3390/s22229014.

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Line-of-sight (LOS) indoor optical wireless communications (OWC) enable a high data rate transmission while potentially suffering from optical channel obstructions. Additional LOS links using diversity techniques can tackle the received signal performance degradation, where channel gains often differ in multiple LOS channels. In this paper, a novel active transmitter detection scheme in spatial modulation (SM) is proposed to be incorporated with signal space diversity (SSD) technique to enable an increased OWC system throughput with an improved bit-error-rate (BER). This transmitter detection scheme is composed of a signal pre-distortion technique at the transmitter and a power-based statistical detection method at the receiver, which can address the problem of power-based transmitter detection in SM using carrierless amplitude and phase modulation waveforms with numerous signal levels. Experimental results show that, with the proposed transmitter detection scheme, SSD can be effectively provided with ~0.61 dB signal-to-noise-ratio (SNR) improvement. Additionally, an improved data rate ~7.5 Gbit/s is expected due to effective transmitter detection in SM. The SSD performances at different constellation rotation angles and under different channel gain distributions are also investigated, respectively. The proposed scheme provides a practical solution to implement power-based SM and thus aids the SSD realization for improving system performance.

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Li, Changxiu, Vitalyi Gusev, Emmanouil Dimakis, Thomas Dekorsy, and Mike Hettich. "Broadband Photo-Excited Coherent Acoustic Frequency Combs and Mini-Brillouin-Zone Modes in a MQW-SESAM Structure." Applied Sciences 9, no. 2 (January 15, 2019): 289. http://dx.doi.org/10.3390/app9020289.

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A multiple quantum-well semiconductor saturable absorber mirror (MQW-SESAM) structure has been investigated by femtosecond pump-probe laser spectroscopy at a central wavelength of around 1050 nm. Coherent acoustic phonons are generated and detected over a wide frequency range from ~15 GHz to ~800 GHz. In the optical absorption region, i.e., in the multiple quantum wells (In0.27Ga0.73As), acoustic frequency combs centered at ~365 GHz, with a comb spacing of ~33 GHz, are generated. Most importantly, in the transparent region, i.e., in the distributed Bragg reflector, which is formed by a non-doped long-period semiconductor GaAs/Al0.95Ga0.05As superlattice, the mini-Brillouin-zone center, as well as zone-edge acoustic modes, are observed. The mini-zone-center modes with a fundamental frequency of 32 GHz can be attributed to the spatial modulation of the pump optical interference field with a period very close to that of the distributed Bragg reflector, in combination with the periodic spatial modulation of the electrostriction coefficient in the distributed Bragg reflector. The excitation of mini-zone-edge modes is attributed to the stimulated subharmonic decay of the fundamental center modes. Their subsequent back-folding to the mini-Brillouin-zone center makes them Raman active for the probe light.

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Gkonis, Panagiotis K., and Dimitra I. Kaklamani. "Reduced Complexity BER Calculations in Large Scale Spatial Multiplexing Multi-User MIMO Orientations in Frequency Selective Fading Environments." Electronics 8, no. 7 (June 26, 2019): 727. http://dx.doi.org/10.3390/electronics8070727.

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In this article, a computationally-efficient approach is presented for Bit Error Rate (BER) calculations in multi-user Multiple Input Multiple Output (MIMO) frequency selective fading environments, operating in spatial multiplexing transmission mode. To this end, theoretical expressions for the equivalent Signal to Interference plus Noise Ratio (SINR) per active user and transmission mode, as well as mean BER, are derived. The key idea is that all parameters related to BER calculations can be expressed as sums of identically distributed random variables (RVs). Hence, computational burden can be reduced, since summation formulas take into account the parameters of a standalone RV along with the correlation of an arbitrary pair of RVs. As results indicate, the proposed approach can accurately estimate mean BER in multiuser MIMO orientations with increased reception diversity order, for arbitrary number of transmit/receive antennas, a modulation scheme, and a number of resolvable multi-path components.

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Lian, Jie, Mohammad Noshad, and Maïté Brandt-Pearce. "Indoor multiuser visible light communication systems using Hadamard-coded modulation." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2169 (March 2, 2020): 20190183. http://dx.doi.org/10.1098/rsta.2019.0183.

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Visible light communications (VLC) is a short-range optical wireless communication technology that uses light-emitting diodes (LEDs) as lighting devices and data transmitters. This paper describes a multiuser VLC system using Hadamard-coded modulation (HCM) for indoor data transmission. Considering the peak transmitted power limit of the LEDs, a DC-reduced HCM (DCR-HCM) is used to reduce the nonlinear clipping distortion. Since the Hadamard codewords have different bandwidth requirements for a given symbol rate, they can be assigned to users with varying hardware capabilities. Optimally assigning codewords to users is found to significantly improve the average throughput, up to twice higher than a random assignment for a typical scenario. When the number of active users is less than the size of the Hadamard matrix used, more than one codeword can be assigned per user, which further improves the throughput. This paper also examines a scenario where multiple lamps in an indoor space transmit the same data. Since the time of arrival for the received signals emitted from different lamps is different, the Hadamard codes received are no longer orthogonal, resulting in multiple access interference and inter-chip interference. The number of acceptable codewords is computed based on the specific interference experienced in different parts of the indoor space. The spatial distribution of the maximum throughput is also simulated, showing that the ratio of the maximum to the minimum data rate can be as high as 10 when considering the entire area of a typical indoor room. This article is part of the theme issue ‘Optical wireless communication’.

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Brosch, Tobias, Didier Grandjean, David Sander, and Klaus R. Scherer. "Cross-modal Emotional Attention: Emotional Voices Modulate Early Stages of Visual Processing." Journal of Cognitive Neuroscience 21, no. 9 (September 2009): 1670–79. http://dx.doi.org/10.1162/jocn.2009.21110.

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Emotional attention, the boosting of the processing of emotionally relevant stimuli, has, up to now, mainly been investigated within a sensory modality, for instance, by using emotional pictures to modulate visual attention. In real-life environments, however, humans typically encounter simultaneous input to several different senses, such as vision and audition. As multiple signals entering different channels might originate from a common, emotionally relevant source, the prioritization of emotional stimuli should be able to operate across modalities. In this study, we explored cross-modal emotional attention. Spatially localized utterances with emotional and neutral prosody served as cues for a visually presented target in a cross-modal dot-probe task. Participants were faster to respond to targets that appeared at the spatial location of emotional compared to neutral prosody. Event-related brain potentials revealed emotional modulation of early visual target processing at the level of the P1 component, with neural sources in the striate visual cortex being more active for targets that appeared at the spatial location of emotional compared to neutral prosody. These effects were not found using synthesized control sounds matched for mean fundamental frequency and amplitude envelope. These results show that emotional attention can operate across sensory modalities by boosting early sensory stages of processing, thus facilitating the multimodal assessment of emotionally relevant stimuli in the environment.

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Furber, Backlund, Yergey, and Coorssen. "Unbiased Thiol-Labeling and Top-Down Proteomic Analyses Implicate Multiple Proteins in the Late Steps of Regulated Secretion." Proteomes 7, no. 4 (September 27, 2019): 34. http://dx.doi.org/10.3390/proteomes7040034.

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Regulated exocytosis enables temporal and spatial control over the secretion of biologically active compounds; however, the mechanism by which Ca2+ modulates different stages of exocytosis is still poorly understood. For an unbiased, top-down proteomic approach, select thiol- reactive reagents were used to investigate this process in release-ready native secretory vesicles. We previously characterized a biphasic effect of these reagents on Ca2+-triggered exocytosis: low doses potentiated Ca2+ sensitivity, whereas high doses inhibited Ca2+ sensitivity and extent of vesicle fusion. Capitalizing on this novel potentiating effect, we have now identified fluorescent thiol- reactive reagents producing the same effects: Lucifer yellow iodoacetamide, monobromobimane, and dibromobimane. Top-down proteomic analyses of fluorescently labeled proteins from total and cholesterol-enriched vesicle membrane fractions using two-dimensional gel electrophoresis coupled with mass spectrometry identified several candidate targets, some of which have been previously linked to the late steps of regulated exocytosis and some of which are novel. Initial validation studies indicate that Rab proteins are involved in the modulation of Ca2+ sensitivity, and thus the efficiency of membrane fusion, which may, in part, be linked to their previously identified upstream roles in vesicle docking.

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Chung, Yoonjae, Ranjit Shrestha, Seungju Lee, and Wontae Kim. "Binarization Mechanism Evaluation for Water Ingress Detectability in Honeycomb Sandwich Structure Using Lock-In Thermography." Materials 15, no. 6 (March 21, 2022): 2333. http://dx.doi.org/10.3390/ma15062333.

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The growing use of composite honeycomb structures in several industries including aircraft has demonstrated the need to develop effective and efficient non-destructive evaluation methods. In recent years, active thermography has attracted great interest as a reliable technology for non-destructive testing and evaluation of composite materials due to its advantages of non-contact, non-destructive, full-area coverage, high speed, qualitative, and quantitative testing. However, non-uniform heating, low spatial resolution, and ambient environmental noise make the detection and characterization of defects challenging. Therefore, in this study, lock-in thermography (LIT) was used to detect water ingress into an aircraft composite honeycomb sandwich structure, and the phase signals were binarized through the Otsu algorithm. A square composite honeycomb with dimensions of 210 mm × 210 mm along with 16 different defective areas of various sizes in groups filled with water by 25%, 50%, 75%, and 100% of the cell volume was considered. The sample was excited at multiple modulation frequencies (i.e., 1 Hz to 0.01 Hz). The results were compared in terms of phase contrast and CNR according to the modulation frequency. In addition, the detectability was analyzed by comparing the number of pixels of water ingress in the binarized image and the theoretical calculation.

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Takahashi, Muneyoshi, Hiroshi Nishida, A. David Redish, and Johan Lauwereyns. "Theta phase shift in spike timing and modulation of gamma oscillation: a dynamic code for spatial alternation during fixation in rat hippocampal area CA1." Journal of Neurophysiology 111, no. 8 (April 15, 2014): 1601–14. http://dx.doi.org/10.1152/jn.00395.2013.

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Although hippocampus is thought to perform various memory-related functions, little is known about the underlying dynamics of neural activity during a preparatory stage before a spatial choice. Here we focus on neural activity that reflects a memory-based code for spatial alternation, independent of current sensory and motor parameters. We recorded multiple single units and local field potentials in the stratum pyramidale of dorsal hippocampal area CA1 while rats performed a delayed spatial-alternation task. This task includes a 1-s fixation in a nose-poke port between selecting alternating reward sites and so provides time-locked enter-and-leave events. At the single-unit level, we concentrated on neurons that were specifically active during the 1-s fixation period, when the rat was ready and waiting for a cue to pursue the task. These neurons showed selective activity as a function of the alternation sequence. We observed a marked shift in the phase timing of the neuronal spikes relative to the theta oscillation, from the theta peak at the beginning of fixation to the theta trough at the end of fixation. The gamma-band local field potential also changed during the fixation period: the high-gamma power (60–90 Hz) decreased and the low-gamma power (30–45 Hz) increased toward the end. These two gamma components were observed at different phases of the ongoing theta oscillation. Taken together, our data suggest a switch in the type of information processing through the fixation period, from externally cued to internally generated.

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Griffiths, A. D., J. Herrnsdorf, J. J. D. McKendry, M. J. Strain, and M. D. Dawson. "Gallium nitride micro-light-emitting diode structured light sources for multi-modal optical wireless communications systems." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2169 (March 2, 2020): 20190185. http://dx.doi.org/10.1098/rsta.2019.0185.

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Gallium nitride-based light-emitting diodes (LEDs) have revolutionized the lighting industry with their efficient generation of blue and green light. While broad-area (square millimetre) devices have become the dominant LED lighting technology, fabricating LEDs into micro-scale pixels (micro-LEDs) yields further advantages for optical wireless communications (OWC), and for the development of smart-lighting applications such as tracking and imaging. The smaller active areas of micro-LEDs result in high current density operation, providing high modulation bandwidths and increased optical power density. Fabricating micro-LEDs in array formats allows device layouts to be tailored for target applications and provides additional degrees of freedom for OWC systems. Temporal and spatial control is crucial to use the full potential of these micro-scale sources, and is achieved by bonding arrays to pitch-matched complementary metal-oxide-semiconductor control electronics. These compact, integrated chips operate as digital-to-light converters, providing optical signals from digital inputs. Applying the devices as projection systems allows structured light patterns to be used for tracking and self-location, while simultaneously providing space-division multiple access communication links. The high-speed nature of micro-LED array devices, combined with spatial and temporal control, allows many modes of operation for OWC providing complex functionality with chip-scale devices. This article is part of the theme issue ‘Optical wireless communication’.

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Hanchate, Seema M., and Shikha Nema. "ISSOR Signal Detection for Energy Efficient and Low Complexity Large Scale MIMO System." International Journal of Engineering and Advanced Technology 9, no. 1s5 (December 30, 2019): 327–34. http://dx.doi.org/10.35940/ijeat.a1381.1291s519.

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Scalable version of multiuser MIMO called Large-scale MIMO is a one of the powerful technology in future wireless communication systems in which huge amount of BS (base station) antennas utilized to process multiple user equipment. Energy consumed is high with more antennas and also it leads to increase the signal detection complexity and overall circuit power consumption. Designing energy efficient and low complexity MIMO system is considered as a challenging issue. This paper presents the ISSOR signal detection for energy efficient and low complexity large scale MIMO system. VA-GSM (Variable Antenna Generalized spatial modulation) is used in which the number of active antenna transmissions are varied for every transmission in the large scale MIMO. In transmitter side, Eigen value based approach is used for antenna selection. Then, improved symmetric successive over relaxation (ISSOR) approach is proposed for low complexity signal detection in receiver side. The number of user equipment, transmit power, as well as the amount of antennas at the base station, are considered as the optimal system parameters which are chosen for enhancing the efficiency of utilized energy in the system. The proposed scheme implemented in MATLAB software. The proposed scheme attained the high energy efficiency compared to other approaches. Moreover, the BER is utilized to estimate the performance of an offered algorithm and also compared to the previously determined algorithm of existing literatures.

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Dou, Yujiang, Haibo Chen, Yuke Ge, Kai Yang, and Bing Yuan. "Heterogeneous Structural Disturbance of Cell Membrane by Peptides with Modulated Hydrophobic Properties." Pharmaceutics 14, no. 11 (November 15, 2022): 2471. http://dx.doi.org/10.3390/pharmaceutics14112471.

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Extensive effort has been devoted to developing new clinical therapies based on membrane-active peptides (MAPs). Previous models on the membrane action mechanisms of these peptides mostly focused on the MAP–membrane interactions in a local region, while the influence of the spatial heterogeneity of the MAP distribution on the membrane was much ignored. Herein, three types of natural peptide variants, AS4-1, AS4-5, and AS4-9, with similar amphiphilic α-helical structures but distinct hydrophobic degrees (AS4-1 < AS4-5 < AS4-9) and net charges (+9 vs. +7 vs. +5), were used to interact with a mixed phosphatidylcholine (PC) and phosphatidylglycerol (PG) membrane. A combination of giant unilamellar vesicle (GUV) leakage assays, atomic force microscopy (AFM) characterizations, and molecular dynamics (MD) simulations demonstrated the coexistence of multiple action mechanisms of peptides on a membrane, probably due to the spatially heterogeneous distribution of peptides on the membrane surface. Specifically, the most hydrophobic peptide (i.e., AS4-9) had the strongest membrane binding, perturbation, and permeabilization effects, leading to the formation of large peptide–lipid aggregates (10 ± 5 nm in height and 150 ± 50 nm in size), as well as continuous fragments and ridges on the supported membrane surface. The AS4-5 peptides, with a half-hydrophilic and half-hydrophobic structure, induced membrane lysis in addition to reconstruction. The most hydrophilic peptide AS4-1 only exhibited unstable binding on the supported membrane surface. These results demonstrate the heterogeneous structural disturbance of model cell membranes by amphiphilic α-helical peptides, which could be significantly strengthened by increasing the degree of hydrophobicity and/or local number density of peptides. This work provides support for the modulation of the membrane activity of MAPs by adjusting their hydrophobicity and local concentration.

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Dasika, Vasant K., John A. White, and H. Steven Colburn. "Simple Models Show the General Advantages of Dendrites in Coincidence Detection." Journal of Neurophysiology 97, no. 5 (May 2007): 3449–59. http://dx.doi.org/10.1152/jn.00669.2005.

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Dendrites can influence and improve information processing in single neurons. Here, simple models are used to elucidate mechanisms underlying the dendritic enhancement of coincidence detection. We focus on coincidence-detecting cells in the auditory system, which have bipolar dendrites and show acute sensitivity to interaural time difference (ITD), a critical cue for spatial hearing. A three-compartment model consisting of a single-compartment soma and two single-compartment dendrites is primarily used, although multiple-compartment dendrites are also tested. Two varieties of somata, with and without active ion channels, are studied. Using constant conductance inputs, we show analytically that the somatic response to balanced bilateral inputs is largest, whereas the response monotonically decreases as the input distribution becomes increasingly monolateral. This enhancement is a consequence of the sublinear saturating dendritic voltage response to conductance input and occurs when dendrites are composed of a single compartment or either a finite number or an infinite number (i.e., a cable) of compartments. Longer, thinner dendrites or greater numbers of compartments increase the enhancement of the somatic response to bilateral input. The time-independent dendritic enhancement, moreover, underlies improved coincidence detection of time-varying input. Coincidence sensitivity to a pair of conductance pulses and rate–ITD modulation to low-frequency (400-Hz) periodic inputs increases with dendritic length. These findings are related to the length gradient in the avian system, where low characteristic frequency (CF) cells have long dendrites and high CF cells have short dendrites. We conclude that dendrites fundamentally improve coincidence detection, increasing the computational power of many neurons in the nervous system.

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Lo, Chun-Min, Linda C. Samuelson, James Brad Chambers, Alexandra King, Justin Heiman, Ronald J. Jandacek, Randall R. Sakai, et al. "Characterization of mice lacking the gene for cholecystokinin." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 294, no. 3 (March 2008): R803—R810. http://dx.doi.org/10.1152/ajpregu.00682.2007.

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CCK acts peripherally as a satiating peptide released during meals in response to lipid feeding and centrally functions in the modulation of feeding, exploratory, and memory activities. The present study determined metabolic parameters, food intake, anxiety-like behaviors, and cognitive function in mice lacking the CCK gene. We studied intestinal fat absorption, body composition, and food intake of CCK knockout (CCK-KO) mice by using the noninvasive measurement of intestinal fat absorption along with quantitative magnetic resonance (QMR) imaging and the DietMax system, respectively. Additionally, exploratory and memory capacities were assessed by monitoring running wheel activity and conducting elevated plus-maze and Morris water-maze tests with these mice. Compared with wild-type (WT) littermate controls, CCK-KO mice had normal food intake, fat absorption, body weight, and body mass. CCK-KO mice ate more food than control animals during the light period and less food during the dark period. Energy expenditure was unchanged between the genotypes; however, CCK-KO mice displayed greater fatty acid oxidation. CCK-KO mice were as active as WT animals in the running wheel test. CCK-KO mice spent more time in the closed arms of an elevated plus-maze, indicative of increased anxiety. Additionally, CCK-KO mice exhibited attenuated performance in a passive avoidance task and impaired spatial memory in the Morris water maze test. We conclude that CCK is involved in metabolic rate and is important for memory and exploration. CCK is intimately involved in multiple processes related to cognitive function and food intake regulation.

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Osman, Onur. "Variable active antenna spatial modulation." IET Microwaves, Antennas & Propagation 9, no. 15 (December 2015): 1816–24. http://dx.doi.org/10.1049/iet-map.2014.0683.

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Sudhamsu, Jawahar, Nicholas Liau, Timothy Wendorff, Saeed Izadi, and Luca Gerosa. "Abstract PR02: Factors modulating RAF dimerization downstream of RAS – A mechanistic overview." Molecular Cancer Research 21, no. 5_Supplement (May 1, 2023): PR02. http://dx.doi.org/10.1158/1557-3125.ras23-pr02.

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Abstract The RAS-RAF pathway is one of the most commonly dysregulated in human cancers. The activation of this pathway is tightly regulated with appropriate spatial and temporal signaling cues. The central step in activation of this pathway is the dimerization of RAF kinases. Recent advances in biochemical, enzymatic and structural characterization of various multiprotein complexes in this pathway provide insight into various modes of RAF activity modulation. Kinase RAF and its substrate MEK exist as a pre-formed complex prior to pathway activation. Multiple factors prevent MEK phosphorylation by RAF in this pre-formed complex, including phosphorylation of a Serine residue N-terminal to the kinase domain, which enables 14-3-3 to trap RAF as a monomer. One of our intriguing findings is that cellular ATP exerts a negative regulatory effect on RAF kinase and stabilizes the inactive conformation of RAF monomer. We characterize this negative regulatory effect of ATP of RAF kinase structurally by solving a RAF-ATP complex and enzymology. Upon membrane recruitment of RAF by RAS-GTP, dephosphorylation of the above-mentioned serine residue in RAF occurs by a multiprotein complex composed of phosphatase PP1C, a scaffolding protein SHOC2 and RAS-GTP. We solved the structure of this RAS-SHOC2-PP1C complex and performed a thorough enzymatic analysis of this complex for RAF dephosphorylation. Our results show that RAF specificity is determined by SHOC2 and RAS GTP is responsible for spatial localization both inactive RAF and SHOC2/PP1C to the membrane. This dephosphorylation results in RAF being stabilized as a dimer by 14-3-3, which now binds to phospho-serine residues C-terminal to the kinase domain (S729 in BRAF) in 2 RAF molecules. We solve a structure of the RAF-14-3-3 complex. 14-3-3 induced RAF dimerization increases activity of RAF ~500 fold. Further, oncogenic mutations in RAF and MEK occur basally in tumors, and additional mutations are induced upon pathway inhibitor treatment in the clinic, especially for recent KRAS-G12C treatments. These mutations include RAF mutations that either activate or inactivate the kinase activity of the mutated RAF, but nevertheless result in pathway activation. Our data suggests that these mutations appear to tilt the RAF monomer-dimer equilibrium towards RAF dimer. The molecular mechanism of how the MEK mutations active the pathway in poorly understood. Biochemical and structural characterization of these mutations occurring in MEK kinases suggests that the mechanism of activation is also likely functioning via promoting RAF dimerization. This RAF dimer promotion appears to mechanistically work by relieving the negative regulatory effect of RAF by ATP to result in the “just-right” amount of pathway activation to sustain tumor growth. A comprehensive understanding of the various factors modulating RAF dimerization in the context of normal cell and cancer cells that depend on this pathway can pave the way for more precise interventions for treatment of cancers that depend on the RAS pathway. Citation Format: Jawahar Sudhamsu, Nicholas Liau, Timothy Wendorff, Saeed Izadi, Luca Gerosa. Factors modulating RAF dimerization downstream of RAS – A mechanistic overview [abstract]. In: Proceedings of the AACR Special Conference: Targeting RAS; 2023 Mar 5-8; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Res 2023;21(5_Suppl):Abstract nr PR02.

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Altın, Gökhan, Ümit Aygölü, Ertugrul Basar, and Mehmet E. Çelebi. "Multiple-input–multiple-output cooperative spatial modulation systems." IET Communications 11, no. 15 (October 19, 2017): 2289–96. http://dx.doi.org/10.1049/iet-com.2016.0977.

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Cogalan, T., H. Haas, and E. Panayirci. "Optical spatial modulation design." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2169 (March 2, 2020): 20190195. http://dx.doi.org/10.1098/rsta.2019.0195.

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Visible light communication (VLC) systems are inherently signal-to-noise ratio (SNR) limited due to link budget constraints. One favourable method to overcome this limitation is to focus on the pre-log factors of the channel capacity. Multiple-input multiple-output (MIMO) techniques are therefore a promising avenue of research. However, inter-channel interference in MIMO limits the achievable capacity. Spatial modulation (SM) avoids this limitation. Furthermore, the performance of MIMO systems in VLC is limited by the similarities among spatial channels. This limitation becomes particularly severe in intensity modulation/direct detection (IM/DD) systems because of the lack of phase information. The motivation of this paper is to propose a system that results in a multi-channel transmission system that enables reliable multi-user optical MIMO SM transmission without the need for a precoder, power allocation algorithm or additional optics at the receiver. A general bit error performance model for the SM system is developed for an arbitrary number of light-emitting diodes (LEDs) in conjunction with pulse amplitude modulation. Based on this model, an LED array structure is designed to result in spatially separated multiple channels by manipulating the transmitter geometry. This article is part of the theme issue ‘Optical wireless communication’.

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Kumar, Anupam, Katharine Chen, Claudia Petritsch, Theodore Nicolaides, Mariarita Santi-Vicini, Arie Perry, Andrew Bollen, David Solomon, Annette M. Molinaro, and Joanna Phillips. "TAMI-07. THE IMMUNE MICROENVIRONMENT IN LOWER GRADE GLIOMAS." Neuro-Oncology 22, Supplement_2 (November 2020): ii214. http://dx.doi.org/10.1093/neuonc/noaa215.896.

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Abstract The determinants of the tumor-associated immune response in brain tumors are poorly understood. Using tumor samples from two molecularly distinct subtypes of lower grade glioma, MAPK-driven glioma with biallelic inactivation of CDKN2A (n=30) and IDH-mutant, 1p/19q-intact astrocytoma (n=29), we demonstrate qualitative and quantitative differences in the tumor-associated immune response and we investigate the molecular mechanisms involved. Histologically the MAPK-driven gliomas were comprised of pleomorphic xanthoastrocytoma (PXA) (n=11) and anaplastic PXA (n=19). Seven patients had paired samples from two sequential surgeries. Immune cell populations and their activity were determined by quantitative multiplex immunostaining and Digital Spatial Profiling and gene expression was analyzed by Nanostring. Functional studies were performed using established cell lines and two new patient-derived lines from MAPK-driven LGGs. MAPK-driven tumors exhibited an increased number of CD8+ T cells and tumor-associated microglial/macrophage (TAMs), including CD163+ TAMs, as compared to IDH-mutant astrocytoma. In contrast, IDH-mutant tumors had increased FOXP3+ immunosuppressive T regulatory cells. Transcriptional and protein level analyses in MAPK-driven tumors suggested an active cytotoxic T cell response with robust expression of granzyme B, present on 27% of CD8+ T cells, increased MHC class I expression, and altered cytokine profiles. Interestingly, MAPK-driven tumors also had increased expression of immunosuppressive molecules, including CXCR4, PD-L1, and VEGFA. Expression differences for cell surface and secreted proteins were confirmed in patient-derived tumor lines and functional relationships between altered chemokine expression and immune cell infiltration was investigated. Our data provide novel insights into the immune contexture of MAPK driven LGGs and suggest MAPK driven gliomas with biallelic inactivation of CDKN2A may be particularly vulnerable to immunotherapeutic modulation

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Hafez, Mohammed, Marwan Yusuf, Tamer Khattab, Tarek Elfouly, and Huseyin Arslan. "Secure Spatial Multiple Access Using Directional Modulation." IEEE Transactions on Wireless Communications 17, no. 1 (January 2018): 563–73. http://dx.doi.org/10.1109/twc.2017.2768419.

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Cheng, Chien-Chun, Hikmet Sari, Serdar Sezginer, and Yu T. Su. "Enhanced Spatial Modulation With Multiple Signal Constellations." IEEE Transactions on Communications 63, no. 6 (June 2015): 2237–48. http://dx.doi.org/10.1109/tcomm.2015.2422306.

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Wang, Yanrui, Wenhui Xiong, Yue Xiao, Shu Fang, You Li, and Chen Zheng. "Offset Spatial Modulation With Multiple Receive Antennas." IEEE Access 8 (2020): 100542–50. http://dx.doi.org/10.1109/access.2020.2991587.

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36

Medendorp, W. P., B. J. M. Melis, C. C. A. M. Gielen, and J. A. M. Van Gisbergen. "Off-Centric Rotation Axes in Natural Head Movements: Implications for Vestibular Reafference and Kinematic Redundancy." Journal of Neurophysiology 79, no. 4 (April 1, 1998): 2025–39. http://dx.doi.org/10.1152/jn.1998.79.4.2025.

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Medendorp, W. P., B.J.M. Melis, C.C.A.M. Gielen, and J.A.M. Van Gisbergen. Off-centric rotation axes in natural head movements: implications for vestibular reafference and kinematic redundancy. J. Neurophysiol. 79: 2025–2039, 1998. Until now, most studies concerning active head movements in three dimensions have used the classical rotation vector description. Although this description yields both the orientation of the head rotation axis and the amount of rotation, it is incomplete because it cannot specify the location of this rotation axis in space. The latter is of importance for a proper picture of the vestibular consequences of active head movements and has relevance for the problem of how the brain deals with the inherent kinematic redundancy of the multijoint head-neck system. With this in mind, we have extended the rotation vector description by applying the helical axes approach, which yields both the classical rotation vector as well as the location of the rotation axis in space. Subjects ( n = 7), whose head movements were recorded optically, were instructed to shift gaze naturally to targets in 12 different directions at an eccentricity of 40°. The results demonstrate that the axes for these head movements occupy consistently different spatial locations. For purely horizontal movements, the rotation axis is located near a point midway between the two ear canals. For gaze shifts in other directions, the rotation axes are located below the ear canals along two circles, one for movements with an upward component (up circle), the other (typically larger in size) for movements with a downward component (down circle). Purely vertical movement (up and down) axes were located on the lower pole of the up and down circles, respectively. It was found that both circles, the upper poles of which coincided, became larger in size as movement amplitude increased, which means that the axis location shifts to lower and more eccentric locations with respect to the skull for larger flexion and extension movements. Although this pattern could be recognized in most subjects, there were consistent intersubject differences in the absolute size of the circles, their increase with movement amplitude, and in the relative sizes of the up and down circles. Because multiple vertebrae are involved in head movements, there are theoretically many possibilities to execute a certain head movement. The differences in circle patterns among subjects indicate different strategies in resolving this kinematic redundancy problem, a fact that was not apparent from the classical rotation vector part of our description, which yielded a rather uniform picture. A simple model suggests that the downward shift of the location of the rotation axis requires a modulation in vestibulo-ocular reflex gain of ≤10% to maintain fixation of a near target during vertical head movement. The involvement of the otolith system in this process remains to be determined.

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Gadhai, Shyam, and Rohit Budhiraja. "Joint-Mapping-Based Variable Active Antenna Spatial Modulation." IEEE Wireless Communications Letters 9, no. 10 (October 2020): 1668–72. http://dx.doi.org/10.1109/lwc.2020.3001003.

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Kilfoyle, D. B., J. C. Preisig, and A. B. Baggeroer. "Spatial modulation over partially coherent multiple-input/multiple-output channels." IEEE Transactions on Signal Processing 51, no. 3 (March 2003): 794–804. http://dx.doi.org/10.1109/tsp.2002.808118.

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Lai, I.-Wei, Jhih-Wei Shih, Che-Wei Lee, Hsu-Hsuan Tu, Jung-Chun Chi, Jyun-Sian Wu, and Yuan-Hao Huang. "Spatial Permutation Modulation for Multiple-Input Multiple-Output (MIMO) Systems." IEEE Access 7 (2019): 68206–18. http://dx.doi.org/10.1109/access.2019.2918710.

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Mohaisen, Manar. "Generalized Complex Quadrature Spatial Modulation." Wireless Communications and Mobile Computing 2019 (April 28, 2019): 1–12. http://dx.doi.org/10.1155/2019/3137927.

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Spatial modulation (SM) is a multiple-input multiple-output (MIMO) system that achieves a MIMO high spectral efficiency while maintaining the transmitter computational complexity and requirements as low as those of the single-input systems. The complex quadrature spatial modulation (CQSM) builds on the QSM scheme and improves the spectral efficiency by transmitting two signal symbols at each channel use. In this paper, we propose two generalizations of CQSM, namely, generalized CQSM with unique combinations (GCQSM-UC) and with permuted combinations (GCQSM-PC). These two generalizations perform close to CQSM or outperform it, depending on the system parameters. Also, the proposed schemes require much less transmit antennas to achieve the same spectral efficiency of CQSM, for instance, assuming 16-QAM, GCQSM-PC, and GCQSM-UC require 10 and 15 transmit antennas, respectively, to achieve the same spectral of CQSM which is equipped with 32 antennas.

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Liu, Yusha, Lie-Liang Yang, and Lajos Hanzo. "Spatial Modulation Aided Sparse Code-Division Multiple Access." IEEE Transactions on Wireless Communications 17, no. 3 (March 2018): 1474–87. http://dx.doi.org/10.1109/twc.2017.2778722.

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Du, Yuyang, Jialing Chen, Yiming Lei, and Xiaolong Hao. "Performance analysis of nonlinear spatial modulation multiple-input multiple-output systems." Digital Signal Processing 115 (August 2021): 103064. http://dx.doi.org/10.1016/j.dsp.2021.103064.

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Yang, Ping, Yue Xiao, Yong Liang Guan, Shaoqian Li, and Lajos Hanzo. "Transmit Antenna Selection for Multiple-Input Multiple-Output Spatial Modulation Systems." IEEE Transactions on Communications 64, no. 5 (May 2016): 2035–48. http://dx.doi.org/10.1109/tcomm.2016.2547900.

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Murtala, Sheriff, Nishal Muchena, Tasnim Holoubi, Manar Mohaisen, and Kang-Sun Choi. "Parallel Complex Quadrature Spatial Modulation." Applied Sciences 11, no. 1 (December 31, 2020): 330. http://dx.doi.org/10.3390/app11010330.

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In this paper, we propose a new multiple-input multiple-output (MIMO) transmission scheme, called parallel complex quadrature spatial modulation (PCQSM). The proposed technique is based on the complex quadrature spatial modulation (CQSM) to further increase the spectral efficiency of the communication system. CQSM transmits two different complex symbols at each channel use. In contrast with CQSM, the new transmission scheme splits the transmit antennas into groups, and modulates the two signal symbols using the conventional CQSM before transmission. Based on the selected modulation order and the number of possible groups that can be realized, the incoming bits modulate the two signal symbols and the indices of the transmit antennas in each group. We demonstrated that while the complexity and performance of the proposed scheme is the same as that of CQSM, the number of required transmit antennas is significantly reduced. The proposed PCQSM achieves such a benefit without requiring any additional radio frequency (RF) chains. The results obtained from Monte Carlo simulation showed that at a Bit Error Rate (BER) of 10−4, the performance of the PCQSM with two antenna groups closely matches that of CQSM, and outperformed quadrature spatial modulation (QSM) and parallel quadrature spatial modulation (PQSM) by over 0.7 dB. As the number of antenna groups increased to 4, the BER performance of PCQSM with reduced number of transmit antenna and modulation order matches that of QSM. The BER of the proposed scheme using maximum likelihood (ML) receiver is also analyzed theoretically and compared with the BER obtained via simulations.

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Kumari, Prabha. "A Survey on Spatial Modulation and MIMO System for Emerging Wireless Communication." International Journal for Research in Applied Science and Engineering Technology 9, no. VI (June 30, 2021): 3059–62. http://dx.doi.org/10.22214/ijraset.2021.35590.

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In this paper we have studied about Spatial Modulation (SM) in MIMO system. Spatial modulation is a unique and newly proposed technique. Spatial modulation is a multiple input multiple output technique which provides higher throughput and gain as compared to Quadrature Amplitude Modulation. Spatial modulation is a technique which enhances the performance of MIMO system. Spatial modulation and MIMO technique are used to attracted research for its high energy and spectral efficiency because it is working on single RF chain. This paper has considered the advantages of spatial modulation and MIMO systems, using different technique to improve the bandwidth efficiency. Some of such MIMO systems applications are discussed wherein become a requirement for an emerging wireless communication system.

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Chen, Jixiang, Hua Yu, Quansheng Guan, Gang Yang, and Ying-Chang Liang. "Spatial Modulation Based Multiple Access for Ambient Backscatter Networks." IEEE Communications Letters 26, no. 1 (January 2022): 197–201. http://dx.doi.org/10.1109/lcomm.2021.3124277.

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Zhong, Caijun, Xiaoling Hu, Xiaoming Chen, Derrick Wing Kwan Ng, and Zhaoyang Zhang. "Spatial Modulation Assisted Multi-Antenna Non-Orthogonal Multiple Access." IEEE Wireless Communications 25, no. 2 (April 2018): 61–67. http://dx.doi.org/10.1109/mwc.2018.1700062.

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Renzo, Marco, Harald Haas, and Peter Grant. "Spatial modulation for multiple-antenna wireless systems: a survey." IEEE Communications Magazine 49, no. 12 (December 2011): 182–91. http://dx.doi.org/10.1109/mcom.2011.6094024.

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An, Zhecheng, Jun Wang, Jintao Wang, Su Huang, and Jian Song. "Mutual Information Analysis on Spatial Modulation Multiple Antenna System." IEEE Transactions on Communications 63, no. 3 (March 2015): 826–43. http://dx.doi.org/10.1109/tcomm.2014.2387171.

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Rubin, Ofira, and Dani Cherkassky. "Spatial active noise reduction with multiple error microphones." Journal of the Acoustical Society of America 129, no. 4 (April 2011): 2584. http://dx.doi.org/10.1121/1.3588544.

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Journal articles on the topic 'Multiple Active Spatial Modulation'

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