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Journal articles on the topic 'Pulse-code modulation'

Author: Grafiati

Published: 4 June 2021

Last updated: 20 February 2023

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1

Chen, Der Chin, and Jing Yuan Su. "Near-Infrared Electro-Optics Modulation Coding Technology Using the Aperture Module with the Changeable Stop." Applied Mechanics and Materials 284-287 (January 2013): 2872–75. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.2872.

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In this paper we demonstrate a new technology in which we use the spatial optical modulation with trigger pulse width and pulse width modulation of light source (LED,LD) to build the near-infrared electro-optics modulation coding system (NIEOMCS). Using the optical coupler to let the pulse modulation near infrared LED collimated light of transmitter enter into an optical fiber and spatial optical modulator, the electro-optics modulation signal is then detected by the photodiode of the receiver. Because of aperture module with three changeable stop sizes and three duty cycles of light signal, there are 27 kinds of code modes in this system. When the receiver aperture is smaller than the correlation length of fading and the observation interval is shorter than the correlation time of fading, the modulation code error rate of the modulation system occurring is less than 0.2%.

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2

B.P., Gbaranwi, and Kabari L.G. "A Comparative Analysis of Image Compression using PCM and DPCM." British Journal of Computer, Networking and Information Technology 4, no. 1 (July 20, 2021): 60–67. http://dx.doi.org/10.52589/bjcnit-kyur6rdw.

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The quality of the signal is essential in digital communication and signal processing. The transmission channel is also important. Modulation is used for effectively transmission of signal. There exist several types of modulation techniques. One of such is the pulse code modulation (PCM). The performance of PCM is however affected by quantization error and noise in the transmission channel, which affects the quality of the output. Against this backdrop, this paper presents the use of differential pulse code modulation (DPCM) so as to address the limitation of pulse code modulation. The simulation environment is MATLAB 2018a. The MATLAB Simulink is used to design the PCM and DPCM systems using appropriate digital processing blocks. The DPCM system shows a significant improvement in terms of error reduction and quality of output.

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3

Whalen, D. H., E. R. Wiley, Philip E. Rubin, and Franklin S. Cooper. "The Haskins Laboratories’ pulse code modulation (PCM) system." Behavior Research Methods, Instruments, & Computers 22, no. 6 (November 1990): 550–59. http://dx.doi.org/10.3758/bf03204440.

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4

Sulaeman, Enceng, Ashari Ashari, Griffani Megiyanto Rahmatullah, and Rifa Hanifatunnisa. "Pembangkitan Sinyal Pulse Code Modulation Berbasis OMAP-L318." JTERA (Jurnal Teknologi Rekayasa) 5, no. 2 (December 26, 2020): 215. http://dx.doi.org/10.31544/jtera.v5.i2.2020.215-220.

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5

O'Reilly, J. J., and Wang Yichao. "Line code design for digital pulse-position modulation." IEE Proceedings F Communications, Radar and Signal Processing 132, no. 6 (1985): 441. http://dx.doi.org/10.1049/ip-f-1.1985.0084.

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6

Liu, Yang, and Guoan Zhang. "Research on Modulations of Wireless Optical Communication System Based on RS Code under Weak Turbulence Atmosphere Channel." Applied Mechanics and Materials 556-562 (May 2014): 4945–49. http://dx.doi.org/10.4028/www.scientific.net/amm.556-562.4945.

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The free space optical (FSO) system model is analyzed based on on-off keying (OOK), pulse position modulation (PPM), differential pulse position modulation (DPPM) and digital pulse interval modulation (DPIM) under the weak turbulence atmosphere. To improve the system performance, one effective way is to use forward error correction (FEC).The bit error rate (BER) calculating formula of uncoded system is derived under all above the modulations firstly, then as a benchmark, under the case of independent with identical distribution, the average bit error rates of RS coded system are derived, respectively. Simulations of the average bit error rate performance of these systems are done. Simulation results show that, PPM has the best bit error rate performance, RS coded is efficient to get the code gain and to improve jamming-rejection capability of system.

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7

Wang, Xuanyin. "ON HYDRAULIC MANIPULATOR CONTROL WITH GENRALIZATION PULSE CODE MODULATION." Chinese Journal of Mechanical Engineering 38, supp (2002): 203. http://dx.doi.org/10.3901/jme.2002.supp.203.

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8

Tomar, Geetam Singh, and Marcus L. George. "Hardware Implementation of Pulse Code Modulation Speech Compression Algorithm." Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology 2, no. 1 (June 30, 2012): 19–26. http://dx.doi.org/10.14257/ajmscahs.2012.06.02.

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9

Azizi, Farouk, Hui Lu, Hillel J. Chiel, and Carlos H. Mastrangelo. "Chemical neurostimulation using pulse code modulation (PCM) microfluidic chips." Journal of Neuroscience Methods 192, no. 2 (October 2010): 193–98. http://dx.doi.org/10.1016/j.jneumeth.2010.07.011.

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10

Bessonov, Yu L., A. Kh Zabrodskiĭ, V. P. Konyaev, V. N. Luk'yanov, S. A. Pashko, V. V. Os'kina, N. V. Shelkov, S. D. Yakubovich, and S. V. Yastrebov. "Direct pulse-code modulation of high-power heterolaser radiation." Soviet Journal of Quantum Electronics 20, no. 10 (October 31, 1990): 1295–96. http://dx.doi.org/10.1070/qe1990v020n10abeh007472.

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11

Maulana, Fajar, Rifa Hanifatunnisa, and Enceng Sulaeman. "Simulasi sistem pembangkit line code pada transmisi Pulse Code Modulation berbasis program C." JITEL (Jurnal Ilmiah Telekomunikasi, Elektronika, dan Listrik Tenaga) 2, no. 1 (March 30, 2022): 67–74. http://dx.doi.org/10.35313/jitel.v2.i1.2022.67-74.

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Konsep dasar dari simulasi sistem pembangkitan line code untuk transmisi Pulse Code Modulation (PCM) yaitu bagian transmisi dari encoding dan decoding pada PCM yang mana mempunyai tugas mengubah bentuk sinyal agar tidak berubah pada saat proses pengiriman. Salah satu pemahaman mengenai sistem komunikasi umumnya dengan instrument sentuhan langsung. Namun, kegiatan praktik menjadi kurang maksimal apalagi dikala pandemi seperti ini yang kegiatan praktik menjadi lebih efisien dan performa yang menurun dari instrument yang memadai juga salah satu penyebabnya. Pada penelitian ini disimulasikan sistem pembangkitan line code pada transmisi PCM yang dapat mengubah bentuk biner dari hasil pengkodean menjadi bentuk line code yang tertuang dalam pemograman bahasa C dengan aplikasi simulasi program. Pengujian dilakukan dengan memasukan 17 deretan data hasil kuantisasi Pulse Amplitudo Modulation (PAM) menjadi bentuk biner yang nantinya akan diubah menjadi bentuk line code. Deretan biner yang digunakan dengan panjang 7-bit yang mana 6-bit sebagai data 1-bit sebagai penanda most significant bit (MSB). Hasil pengujian menunjukan bentuk line code yang telah diimplementasikan sesuai dengan dasar teori.

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12

Wei, Chuan Ting, Quan Li Ning, and Dong Chen. "Research on Multi-Fuze Co-Channel Interference Suppression Based on Pseudorandom Code Phase Modulation." Applied Mechanics and Materials 539 (July 2014): 190–93. http://dx.doi.org/10.4028/www.scientific.net/amm.539.190.

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This paper introduces the working principle of the pseudorandom code phase modulation pulse, analyzes the theoretical foundation of multi-fuze co-channel interference suppression achieved by phase modulation of the signals through pseudorandom coding, and through the calculation and analysis of simulation, verifies the feasibility of the multi-fuze co-channel interference suppression based on pseudorandom code phase modulation.

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13

Lim, Hyung-Chul, Jong Uk Park, Mansoo Choi, Eunseo Park, Ki-Pyoung Sung, and Jung Hyun Jo. "Pulse Broadening Effects on Ranging Performance of a Laser Altimeter with Return-to-Zero Pseudorandom Noise Code Modulation." Sensors 22, no. 9 (April 25, 2022): 3293. http://dx.doi.org/10.3390/s22093293.

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A laser altimeter using code modulation techniques receives a backscattered pulse wider than the transmitted rectangular pulse when scanning a rough or sloped target surface. This leads to degrading the ranging performance in terms of signal-to-noise ratio (SNR) and detection probability. Unlike the pulsed techniques, little work has focused on the pulse broadening effect of the code modulation techniques. In this study, mathematical models were derived to investigate the pulse broadening effect on the ranging performance of a return-to-zero pseudorandom noise (RZPN) laser altimeter. Considering that the impulse response can be approximated by a Gaussian function, the analytical waveform was derived using a new flat-topped multi-Gaussian beam (FMGB) model. The closed-form expressions were also analytically derived for a peak cross-correlation, SNR, and detection probability in terms of the pulse broadening effect. With the use of a three-dimensional model of asteroid Itokawa for practical surface profiles, the analytical expressions were validated by comparing to the results obtained from numerical simulations. It was also demonstrated that the pulse broadening effect dropped down the peak cross-correlation and then deteriorated the ranging performance. These analytical expressions will play an important role in not only designing a laser altimeter using the RZPN code modulation technique but also analyzing its ranging performance.

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14

Lim, Hyung-Chul, Jong Uk Park, Mansoo Choi, Eunseo Park, Ki-Pyoung Sung, and Jung Hyun Jo. "Pulse Broadening Effects on Ranging Performance of a Laser Altimeter with Return-to-Zero Pseudorandom Noise Code Modulation." Sensors 22, no. 9 (April 25, 2022): 3293. http://dx.doi.org/10.3390/s22093293.

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A laser altimeter using code modulation techniques receives a backscattered pulse wider than the transmitted rectangular pulse when scanning a rough or sloped target surface. This leads to degrading the ranging performance in terms of signal-to-noise ratio (SNR) and detection probability. Unlike the pulsed techniques, little work has focused on the pulse broadening effect of the code modulation techniques. In this study, mathematical models were derived to investigate the pulse broadening effect on the ranging performance of a return-to-zero pseudorandom noise (RZPN) laser altimeter. Considering that the impulse response can be approximated by a Gaussian function, the analytical waveform was derived using a new flat-topped multi-Gaussian beam (FMGB) model. The closed-form expressions were also analytically derived for a peak cross-correlation, SNR, and detection probability in terms of the pulse broadening effect. With the use of a three-dimensional model of asteroid Itokawa for practical surface profiles, the analytical expressions were validated by comparing to the results obtained from numerical simulations. It was also demonstrated that the pulse broadening effect dropped down the peak cross-correlation and then deteriorated the ranging performance. These analytical expressions will play an important role in not only designing a laser altimeter using the RZPN code modulation technique but also analyzing its ranging performance.

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15

Uddin, Shahnawaz, Iffat Ansari, and Sameena Naaz. "Low Bit Rate Speech Coding Using Differential Pulse Code Modulation." Advances in Research 8, no. 3 (January 10, 2016): 1–6. http://dx.doi.org/10.9734/air/2016/30234.

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16

Yu, Nanjun, Pengzhao Wang, and Zhiyi Zhuang. "Design of Digital Pulse-Position Modulation System." Journal of Physics: Conference Series 2093, no. 1 (November 1, 2021): 012030. http://dx.doi.org/10.1088/1742-6596/2093/1/012030.

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Abstract Pulse-Position Modulation (PPM) is a modulation method that only makes every pulse in the carrier pulse sequence change with time but without changing the shape and amplitude of the pulse signal. In this paper, a PPM system is designed. Firstly, an appropriate mathematical model is established to represent PPM transmission, and the shape of the pulse signal is designed. After that, we write the code and add a white Gaussian noise channel. Then the transmission process is simulated and visualized. At last, the error rate of the scheme is analyzed and discussed through MATLAB simulation then compared with other modulation methods. The goal of this paper is to study PPM by designing a PPM system fully. Besides, our method is compared with other modulation methods to understand the advantages and disadvantages of PPM. This may help other scholars to design and research the PPM system.

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17

Khazraei, Simin, Mohammad Reza Pakravan, and Mohammad Amin Shoaie. "Efficient modulation technique for optical code division multiple access networks: differential pulse position modulation." IET Optoelectronics 8, no. 5 (October 1, 2014): 181–90. http://dx.doi.org/10.1049/iet-opt.2013.0076.

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18

Dong In Kim. "Combined binary pulse position modulation/biorthogonal modulation for direct-sequence code division multiple access." IEEE Transactions on Communications 47, no. 1 (1999): 22–26. http://dx.doi.org/10.1109/26.747809.

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19

BAI, ZHIQUAN, SHAOYI XU, WEIHUA ZHANG, and KYUNGSUP KWAK. "PERFORMANCE ANALYSIS OF A NOVEL M-ARY CODE SELECTED DS-BPAM UWB COMMUNICATION SYSTEM." Journal of Circuits, Systems and Computers 15, no. 03 (June 2006): 455–66. http://dx.doi.org/10.1142/s0218126606003155.

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A novel M-ary direct sequence ultra wideband (UWB) communication system based on the selection of the direct sequence code is studied in this paper. The proposed M-ary code selected direct sequence bipolar pulse amplitude modulation scheme can achieve high bit rate without increasing the system bandwidth or changing the pulse shape. With the increase of the modulation level M, the system bit error rate will be improved even at lower signal to noise ratio per bit. The exact bit error probability is derived over the AWGN channel and correlation receivers. Both Monte-Carlo simulation and the theoretical analysis prove the efficiency of this M-ary UWB system.

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20

Abbas, Huda Saleh, Mark A. Gregory, and Michael W. Austin. "A New Prime Code for Synchronous Optical Code Division Multiple-Access Networks." Journal of Computer Networks and Communications 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/3192520.

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A new spreading code based on a prime code for synchronous optical code-division multiple-access networks that can be used in monitoring applications has been proposed. The new code is referred to as “extended grouped new modified prime code.” This new code has the ability to support more terminal devices than other prime codes. In addition, it patches subsequences with “0s” leading to lower power consumption. The proposed code has an improved cross-correlation resulting in enhanced BER performance. The code construction and parameters are provided. The operating performance, using incoherent on-off keying modulation and incoherent pulse position modulation systems, has been analyzed. The performance of the code was compared with other prime codes. The results demonstrate an improved performance, and a BER floor of 10−9 was achieved.

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21

Mohammed Ahmed, Ahmed. "BER Improvement Using Error Concealment Technique for Pulse Code Modulation System." Diyala Journal of Engineering Sciences 11, no. 1 (March 1, 2018): 61–63. http://dx.doi.org/10.24237/djes.2018.11110.

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The output of pulse code modulation (PCM) encoder is statistically described; this description is used at the receiver to reduce the error of the received signal. Recently, PCM is the most important form of pulse modulation. Bit errors occur at the transmission of information through the communication system and the amount of error depends on the characteristics of the channel. In this paper, the voice message is sampled greater than Nyquist rate and quantized with scalar quantizer, then the quantized levels are encoded with resolution B bits assigned to each level. The binary data are mapped and transmitted over Gaussian noise channel. The system was designed without channel coding. At the receiver the statistical description is exploited to conceal the errors. The results show that a significant improvement gained in bit error rate that was reduced from 0.078 to 0.052 at 0 dB of Eb N0⁄ by soft decoding, compared to hard decoding.

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22

Ahmed, Iftekhar Uddin, Abdul Kadar Muhammad Masum, and S. M. A. Motakabber. "The proposed model of pulse code modulation encoder for voice frequencies." International Journal of Scientific World 3, no. 1 (April 26, 2015): 152. http://dx.doi.org/10.14419/ijsw.v3i1.4495.

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<p>In this paper, we have developed a hardware-based model of pulse code modulation (PCM) system for voice frequencies. Firstly, we have constructed sample and hold circuit using triggered semiconductor switch (e.g., MOSFET), which is capable of sampling voice signals at 8 kHz according to Nyquist theory. Then an Analogue to Digital Converter (ADC) Integrated Circuit (IC) is introduced to quantize and to digitize of the output of the sample and hold as pulse amplitude modulation (PAM). The converted outputs are 8-bit digital parallel value per sample at a frequency of 8 kHz. Finally, a parallel to serial converter logic is constructed which remains the voice frequency at the accurate time without any delay. The principle feature of this PCM system is that during a final interval of time, it makes a waveform into 8 bit serial code word. An 8-bit shift register with decade counter and flip-flop based logic are providing to this wave-from one after another without any interruptions of the sequences.</p>

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23

Tomar, Rime Raj Singh, and Kapil Jain. "Lossless Image Compression using Differential Pulse Code Modulation and Its purpose." International Journal of Smart Business and Technology 3, no. 1 (June 30, 2015): 15–22. http://dx.doi.org/10.21742/ijsbt.2015.3.1.02.

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24

George, Marcus L., and Geetam Singh Tomar. "Hardware Implementation of Adaptive-Differential Pulse Code Modulation Speech Compression Algorithm." International Journal of Smart Device and Appliance 2, no. 2 (December 30, 2014): 1–10. http://dx.doi.org/10.21742/ijsda.2014.2.2.01.

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25

Zaki, Fayez. "Sequentially Adaptive Differential Pulse Code Modulation Using Adaptive LSP Filters.(Dept.E)." MEJ. Mansoura Engineering Journal 16, no. 2 (August 8, 2021): 1–18. http://dx.doi.org/10.21608/bfemu.2021.187940.

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26

Wang, Xuanyin. "RESEARCH ON THE HYDRAULIC SERVO CONTROL WITH GENERALIZED PULSE CODE MODULATION." Chinese Journal of Mechanical Engineering 36, no. 12 (2000): 14. http://dx.doi.org/10.3901/jme.2000.12.014.

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27

Xiang Jingsong, 向劲松, 吴涛 Wu Tao, 黄胜 Huang Sheng, and 刘焕淋 Liu Huanlin. "Slot Synchronization Aided by Serial Concatenated Pulse Position Modulation Code System." Acta Optica Sinica 36, no. 8 (2016): 0806006. http://dx.doi.org/10.3788/aos201636.0806006.

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28

Tomar, Rime Raj Singh, and Kapil Jain. "Lossless Image Compression using Differential Pulse Code Modulation and Its Purpose." International Journal of Signal Processing, Image Processing and Pattern Recognition 8, no. 9 (September 30, 2015): 249–56. http://dx.doi.org/10.14257/ijsip.2015.8.9.26.

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29

Tomar, Rime Raj Singh, and Kapil Jain. "Lossless Image Compression Using Differential Pulse Code Modulation and Its Application." International Journal of Signal Processing, Image Processing and Pattern Recognition 9, no. 1 (January 31, 2016): 197–202. http://dx.doi.org/10.14257/ijsip.2016.9.1.18.

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30

Wu, Yung-Gi. "Differential pulse code modulation predictor design procedure using a genetic algorithm." Optical Engineering 42, no. 6 (June 1, 2003): 1649. http://dx.doi.org/10.1117/1.1572889.

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31

Daut, David G. "Double predictor differential pulse code modulation algorithm for image data compression." Optical Engineering 32, no. 7 (1993): 1514. http://dx.doi.org/10.1117/12.138573.

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32

Zhenming, Gao. "A matched filter using charge coupled device for pulse-code modulation." Journal of Electronics (China) 2, no. 3 (July 1985): 269–72. http://dx.doi.org/10.1007/bf02783098.

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33

Tang, Yu. "Simulation Research on how to Improve the Range Resolution of Pulse Compression Radar Based on Phase Coding." Applied Mechanics and Materials 143-144 (December 2011): 634–38. http://dx.doi.org/10.4028/www.scientific.net/amm.143-144.634.

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Phase coded radar signal is one of the pulse-pulse modulation signal in the radar system. Based on the characteristics of matched filtering, we theoretically analyze the basic principle of the phase coded compression radar system. In the Matlab platform, we set up a simulation model which is used for matching filter, when the radar transmitting signal is Barke code signal. The simulation results show that Echo signal can obtain certain pulse compression ratio. By the matched filter, the main lobe amplitude of 13 bits Barker code signal is 22 times the rate of side-lobe. 13 bits Barker codes by the matched filter have the maximum pulse compression ratio.

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34

Huang, Qiongdan, Yong Li, Yaoping Zeng, and Yinjuan Fu. "Design and Characteristic Analysis of Multicarrier Chaotic Phase Coded Radar Pulse Train Signal." International Journal of Antennas and Propagation 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/724294.

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By introducing phase code into multicarrier orthogonal frequency division multiplex signal, the multicarrier phase coded (MCPC) radar signal possesses a good spectrum utilization rate and can achieve a good combination of narrowband and wideband processing. Radar pulse train signal not only reserves the high range resolution of monopulse signal, but also has the same velocity resolution performance as continuous wave signal does. In this study, we use the chaotic biphase code generated by Chebyshev mapping to conduct a phase modulation on MCPC pulse train so as to design two different types of multicarrier chaotic phase coded pulse train signal. The ambiguity functions of the two pulse train signals are compared with that of P4 code MCPC pulse train. In addition, we analyze the influences of subcarrier number, phase-modulated bit number, and period number on the pulse train’s autocorrelation performance. The low probability of intercept (LPI) performance of the two signals is also discussed. Simulation results show that the designed pulse train signals have a thumbtack ambiguity function, a periodic autocorrelation side lobe lower than P4 code MCPC pulse train, and excellent LPI performance, as well as the feature of waveform diversity.

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Hussein, Yasmeen M., Basman M. Al-Nedawe, Ammar Hussein Mutlag, and Ameer K. Jawad. "Application of Error Correction Codes RS and LDPC to Enhance the Dicode Pulse Position Modulation." Journal of Hunan University Natural Sciences 49, no. 1 (January 28, 2022): 161–69. http://dx.doi.org/10.55463/issn.1674-2974.49.1.21.

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Dicode Pulse Position Modulation (DiPPM) has been presented as a new coding technique with several improvements over earlier PPM formats. Few analyses and experimental results have been published because it is a new coding scheme. To overcome the problem of bandwidth utilization in current PPM formats, DiPPM can be employed. The line rate is twice as fast as the original data rate. In order to increase DiPPM's error performance, two types of Forward Error Correction (FEC) codes, Reed-Solomon (RS) code and low-density parity-check (LDPC) code, are investigated in this article. When RS and LDPC function at their optimal parameters, the results show an improvement in DiPPM system error performance. The error performance of an uncoded DiPPM system was compared to that of a DiPPM-encoded LDPC system and a system utilizing the Reed-Solomon algorithm. Transmission efficiency is measured by the number of photons per pulse and bandwidth widening. When the bandwidth is 1x103 times or more than the initial data rate, DiPPM with LDPC code exceeds uncoded DiPPM and DiPPM with RS, using 1.821 x 103 photons per pulse, with a codeword length of 27 and code rate of 0.75.

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Jiang, Hongyan, Ning He, Xin Liao, Wasiu Popoola, and Sujan Rajbhandari. "The BER Performance of the LDPC-Coded MPPM over Turbulence UWOC Channels." Photonics 9, no. 5 (May 16, 2022): 349. http://dx.doi.org/10.3390/photonics9050349.

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Turbulence-induced fading is a critical performance degrading factor for underwater wireless optical communication (UWOC) systems. In this paper, we propose a quasi-cyclic (QC) low-density parity-check (LDPC) code with multiple-pulse-position modulation (MPPM) to overcome turbulence-induced fading. MPPM is adopted as a compromise between the low-power efficiency of on–off keying (OOK) and the low bandwidth efficiency of pulse position modulation (PPM). The bit error rate (BER) performance of LDPC-coded MPPM over turbulence UWOC channels is investigated. The log-likelihood ratio (LLR) of MPPM is derived, and a simplified approximation is used for iterative decoding. Subsequently, the closed-form expression of the BER, without forward error correction (FEC) code, is obtained for the generalized-gamma (GG) fading model. Finally, Monte-Carlo (MC) simulation results are provided to demonstrate the correctness of the derived closed-form expressions and the effectiveness of the LDPC code with simplified LLR to improve the BER performance for different MPPM formats over fading channels.

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37

Han, Yang, Djordjevic, Yue, Wang, Qu, and Anderson. "Joint Probabilistic-Nyquist Pulse Shaping for an LDPC-Coded 8-PAM Signal in DWDM Data Center Communications." Applied Sciences 9, no. 23 (November 20, 2019): 4996. http://dx.doi.org/10.3390/app9234996.

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M-ary pulse-amplitude modulation (PAM) meets the requirements of data center communication because of its simplicity, but coarse entropy granularity cannot meet the dynamic bandwidth demands, and there is a large capacity gap between uniform formats and the Shannon limit. The dense wavelength division multiplexing (DWDM) system is widely used to increase the channel capacity, but low spectral efficiency of the intensity modulation/direct detection (IM/DD) solution restricts the throughput of the modern DWDM data center networks. Probabilistic shaping distribution is a good candidate to offer us a fine entropy granularity and efficiently reduce the gap to the Shannon limit, and Nyquist pulse shaping is widely used to increase the spectral efficiency. We aim toward the joint usage of probabilistic shaping and Nyquist pulse shaping with low-density parity-check (LDPC) coding to improve the bit error rate (BER) performance of 8-PAM signal transmission. We optimized the code rate of the LDPC code and compared different Nyquist pulse shaping parameters using simulations and experiments. We achieved a 0.43 dB gain using Nyquist pulse shaping, and a 1.1 dB gain using probabilistic shaping, while the joint use of probabilistic shaping and Nyquist pulse shaping achieved a 1.27 dB gain, which offers an excellent improvement without upgrading the transceivers.

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38

Kwang Soon Kim, D. M. Marom, L. B. Milstein, and Y. Fainman. "Hybrid pulse position modulation/ultrashort light pulse code-division multiple-access systems-part I: fundamental analysis." IEEE Transactions on Communications 50, no. 12 (December 2002): 2018–31. http://dx.doi.org/10.1109/tcomm.2002.806501.

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39

Kord, Reem, Heba Afify, and Manal Abdel Wahed. "Towards Improved Lossless Compression for Mammogram Images using Differential Pulse Code Modulation." Current Medical Imaging Reviews 14, no. 6 (October 31, 2018): 969–75. http://dx.doi.org/10.2174/1573405614666180530081826.

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40

Zhang, Lu, Xiaodan Pang, Oskars Ozolins, Aleksejs Udalcovs, Richard Schatz, Urban Westergren, Gunnar Jacobsen, et al. "Digital mobile fronthaul employing differential pulse code modulation with suppressed quantization noise." Optics Express 25, no. 25 (December 7, 2017): 31921. http://dx.doi.org/10.1364/oe.25.031921.

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Norris, J. F., and D. F. Lovely. "Real-time compression of myoelectric data utilising adaptive differential pulse code modulation." Medical & Biological Engineering & Computing 33, no. 5 (September 1995): 629–35. http://dx.doi.org/10.1007/bf02510779.

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Nah, Jihah, and Jongweon Kim. "Raw Data Recovery from Pulse Code Modulation Pieces in the BitTorrent Environment." International Journal of Multimedia and Ubiquitous Engineering 9, no. 5 (May 31, 2014): 241–50. http://dx.doi.org/10.14257/ijmue.2014.9.5.24.

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Kim, Gunzung, and Yongwan Park. "Suitable Combination of Direct Intensity Modulation and Spreading Sequence for LIDAR with Pulse Coding." Sensors 18, no. 12 (November 30, 2018): 4201. http://dx.doi.org/10.3390/s18124201.

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In the coded pulse scanning light detection and ranging (LIDAR) system, the number of laser pulses used at a given measurement point changes depending on the modulation and the method of spreading used in optical code-division multiple access (OCDMA). The number of laser pulses determines the pulse width, output power, and duration of the pulse transmission of a measurement point. These parameters determine the maximum measurement distance of the LIDAR and the number of measurement points that can be employed per second. In this paper, we suggest possible combinations of modulation and spreading technology that can be used for OCDMA, evaluate their performance and characteristics, and study optimal combinations according to varying operating environments.

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Middlebrooks, John C. "Auditory Cortex Phase Locking to Amplitude-Modulated Cochlear Implant Pulse Trains." Journal of Neurophysiology 100, no. 1 (July 2008): 76–91. http://dx.doi.org/10.1152/jn.01109.2007.

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Cochlear implant speech processors transmit temporal features of sound as amplitude modulation of constant-rate electrical pulse trains. This study evaluated the central representation of amplitude modulation in the form of phase-locked firing of neurons in the auditory cortex. Anesthetized pigmented guinea pigs were implanted with cochlear electrode arrays. Stimuli were 254 pulse/s (pps) trains of biphasic electrical pulses, sinusoidally modulated with frequencies of 10–64 Hz and modulation depths of −40 to −5 dB re 100% (i.e., 1–56.2% modulation). Single- and multiunit activity was recorded from multi-site silicon-substrate probes. The maximum frequency for significant phase locking (limiting modulation frequency) was ≥60 Hz for 42% of recording sites, whereas phase locking to pulses of unmodulated pulse trains rarely exceeded 30 pps. The strength of phase locking to frequencies ≥40 Hz often varied nonmonotonically with modulation depth, commonly peaking at modulation depths around −15 to −10 dB. Cortical phase locking coded modulation frequency reliably, whereas a putative rate code for frequency was confounded by rate changes with modulation depth. Group delay computed from the slope of mean phase versus modulation frequency tended to increase with decreasing limiting modulation frequency. Neurons in cortical extragranular layers had lower limiting modulation frequencies than did neurons in thalamic afferent layers. Those observations suggest that the low-pass characteristic of cortical phase locking results from intracortical filtering mechanisms. The results show that cortical neurons can phase lock to modulated electrical pulse trains across the range of modulation frequencies and depths presented by cochlear implant speech processors.

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Karar, Abdullah S., Raymond Ghandour, Ibrahim Mahariq, Shadi A. Alboon, Issam Maaz, Bilel Neji, and Julien Moussa H. Barakat. "A Programmable Mode-Locked Fiber Laser Using Phase-Only Pulse Shaping and the Genetic Algorithm." Photonics 7, no. 3 (September 4, 2020): 69. http://dx.doi.org/10.3390/photonics7030069.

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A novel, programmable, mode-locked fiber laser design is presented and numerically demonstrated. The laser programmability is enabled by an intracavity optical phase-only pulse shaper, which utilizes the same linearly chirped fiber Bragg grating (LC-FBG) from its two opposite ends to perform real-time optical Fourier transformation. A binary bit-pattern generator (BPG) operating at 20-Gb/s and producing a periodic sequence of 32 bits every 1.6 ns, is subsequently used to drive an optical phase modulator inside the laser cavity. Simulation results indicate stable programmable intensity profiles for each optimized user defined 32 code words. The laser operated in the self-similar mode-locking regime, enabling wave-breaking free operation. The programmable 32 bit code word targeting a specific intensity profile was determined using 100 generations of the genetic algorithm. The control of ultrashort pulse intensity profiles on the picosecond and femtosecond time scales is difficult. The process of stretching and compressing the pulse in the time domain allows for a slower BPG to impose a predefined phase modulation prior to pulse compression. This results in control over the fine features of the intensity profile of the compressed pulse on a picosecond or femtosecond time scale inside the laser cavity. The stability of the proposed scheme depends on the consistency and accuracy of the BPG rise and fall times in practice.

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Kandouci, Chahinaz. "Performances enhancement of underwater wireless optical communications (UWOC) using pulse position modulation." Journal of Optical Communications 43, no. 2 (November 22, 2021): 289–94. http://dx.doi.org/10.1515/joc-2021-0176.

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Abstract In this work, we study the performance analysis of underwater optical wireless communication (UOWC) transmission link by incorporating optical code division multiple access (OCDMA) using pulse position modulation (PPM) to enhance the channel range and cardinality. Bit error rate (BER) variations are examined versus the range, modulation type (on–off keying (OOK), quadrature amplitude modulation (QAM), etc.), number of users as well as the channel attenuation caused by different water types. The power and transmitter inclination angle limitation, of the enhanced system, are also presented in order to determine the threshold for which the minimum BER 10−9 is achievable.

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Doherty, E. Thomas, and Thomas Shipp. "Tape Recorder Effects on Jitter and Shimmer Extraction." Journal of Speech, Language, and Hearing Research 31, no. 3 (September 1988): 485–90. http://dx.doi.org/10.1044/jshr.3103.485.

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To test for possible contamination of acoustic analyses by record/reproduce systems, five sine waves of fixed frequency and amplitude were sampled directly by a computer and recorded simultaneously on four different tape formats (audio and FM reel-to-reel, audio cassette, and video cassette using pulse code modulation). Recordings were digitized on playback and with the direct samples analyzed for fundamental frequency, amplitude, jitter, and shimmer using a zero crossing interpolation scheme. Distortion introduced by any of the data acquisition systems is negligible when extracting average fundamental frequency or average amplitude. For jitter and shimmer estimation, direct sampling or the use of a video cassette recorder with pulse code modulation are clearly superior. FM recorders, although not quite as accurate, provide a satisfactory alternative to those methods. Audio reel-to-reel recordings are marginally adequate for jitter analysis whereas audio cassette recorders can introduce jitter and shimmer values that are greater than some reported values for normal talkers.

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Ahmed, Ali H., and Loay E. George. "Color Image Compression Based on Wavelet, Differential Pulse Code Modulation and Quadtree Coding." Research Journal of Applied Sciences, Engineering and Technology 14, no. 2 (February 15, 2017): 73–79. http://dx.doi.org/10.19026/rjaset.14.3992.

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LIU, Rong. "Control strategy for electro-hydraulic position servo system with generalized pulse code modulation." Chinese Journal of Mechanical Engineering (English Edition) 20, no. 03 (2007): 50. http://dx.doi.org/10.3901/cjme.2007.03.050.

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Elsabrouty, Maha, Martin Bouchard, and Tyseer Aboulnasr. "Receiver-based packet loss concealment for pulse code modulation (PCM G.711) coder." Signal Processing 84, no. 3 (March 2004): 663–67. http://dx.doi.org/10.1016/j.sigpro.2003.10.021.

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