Journal articles: 'QAM'

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Rakhmania, Amalia Eka, Akhmad Mukhibuddin Harvinanda, Hudiono Hudiono, Aad Hariyadi, Hadiwiyatno, and Mochammad Taufik. "Analisis Kinerja Sistem Modulasi Downlink LTE dan 5G pada Kanal AWGN Berbasis MATLAB." Techné : Jurnal Ilmiah Elektroteknika 22, no. 2 (December 5, 2023): 217–40. http://dx.doi.org/10.31358/techne.v22i2.341.

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Pada penelitian ini dilakukan analisis performansi downlink LTE dan 5G dengan menggunakan MATLAB. Penelitian ini bertujuan untuk menganalisis perbandingan kinerja teknik modulasi QPSK, 16-QAM, dan 64-QAM yang digunakan pada downlink LTE dan teknik modulasi QPSK, 16-QAM, 64-QAM, dan 256-QAM pada downlink 5G yang melalui kanal AWGN untuk mengetahui nilai BER pada teknik modulasi yang digunakan. Teknik multiplexing yang digunakan adalah OFDM dan CP-OFDM untuk downlink LTE dan CP-OFDM untuk downlink 5G dengan variasi cyclic prefix yang digunakan adalah kategori ”normal”. Pada downlink LTE, kinerja modulasi QPSK lebih baik dari 16-QAM dan 64-QAM. Pada OFDM, BER QPSK diperoleh 10-19 pada Eb/No 16 dB, BER 16-QAM diperoleh 10-19 pada Eb/No 20 dB dan BER 64-QAM diperoleh 10-8 pada Eb/No 20 dB. Pada CP-OFDM, BER QPSK diperoleh 10-20 pada Eb/No 16 dB, BER 16-QAM diperoleh 10-19 pada Eb/No 20 dB dan BER 64-QAM diperoleh 10-9 pada Eb/No 20 dB. Pada downlink 5G CP-OFDM, kinerja modulasi QPSK lebih baik dari 16-QAM, 64-QAM dan 256-QAM, BER QPSK diperoleh 10-24 pada Eb/No 16 dB, BER 16-QAM diperoleh 10-23 pada Eb/No 20 dB, BER 64-QAM diperoleh 10-14 pada Eb/No 20 dB, dan BER 256-QAM diperoleh 10-7 pada Eb/No 20 dB.

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Ikhsan, Danang Maulana, and Theophilus Wellem. "SIMULASI SKEMA MODULASI 1024-QAM DAN 4096-QAM PADA SISTEM KOMUNIKASI DIGITAL." Jurnal Indonesia : Manajemen Informatika dan Komunikasi 4, no. 3 (September 10, 2023): 1356–64. http://dx.doi.org/10.35870/jimik.v4i3.321.

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Quadrature amplitude modulation (QAM) is a modulation scheme used by digital communication systems to obtain high data rates in bandwidth-limited channels. M-ary QAM schemes with M values greater than 256 are currently used by wireless network standards, such as WiFi 6 and WiFi 7 (final standard will be released in 2024), which use the 1024-QAM and 4096-QAM modulation schemes, respectively. With the continuous development of technology for digital communication systems, both wireline and wireless, it is essential to research regarding advanced modulation schemes. This study discusses the simulation of the 1024-QAM and 4096-QAM modulation schemes using MATLAB software to compare the performance of the two modulation schemes in data transmission through the AWGN channel without using an error control code. The simulation results show that 4096-QAM is superior to 1024-QAM but requires higher Eb/N0 and SNR values. The Eb/N0 value required by the 4096-QAM to achieve a bit error ratio (BER) of 10-4 is 31 dB, while the 1024-QAM requires an Eb/N0 value of 26 dB.

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Marina, Prieska, Anggun Fitrian Isnawati, and Mas Aly Afandi. "Performance Analysis of FBMC O-QAM System Using Varied Modulation Level." JURNAL INFOTEL 12, no. 2 (May 29, 2020): 45–51. http://dx.doi.org/10.20895/infotel.v12i2.482.

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Communication channels that are affected by various disturbances will cause a high Bit Error Rate (BER). To maximize the performance of the channel in the future, Filter Bank Multicarrier (FBMC) technique is used as a renewal of Orthogonal Frequency Division Multiplexing (OFDM). FBMC has better spectrum efficiency properties due to the nature of orthogonality which only divides bandwidth for sub-channels. The purpose of the research was to knowing the performance of FBMC Offset QAM (FBMC O-QAM) which has a variation of modulation levels of 4-QAM, 16-QAM, and 64-QAM. The Zero Forcing (ZF) method is used to detect the original signal sent by the transmitting antenna. System performance in this study was measured by parameter Bit Error Rate (BER) and channel capacity. The results showed that the FBMC O-QAM system with ZF has decreased BER value on each modulation. At the time of modulation 4 QAM has a BER value of 0.0008945 with an SNR value of 20 dB. Modulation 16 QAM also experienced the same thing when the SNR value of 20 dB has BER value of 0.001856, and at modulation 64 QAM has BER value of 0.01766 at a SNR of 20 dB. Besides decreasing the BER parameters, the FBMC O-QAM ZF system has own characterize in channel capacity. For the 4-QAM has 4.808 b/s/Hz, 16-QAM has 4.627 b/s/Hz, and 64-QAM has 3.903 b/s/Hz at SNR 20 dB. It conclude that 4-QAM has a best channel capacity enhancement. The value of channel capacity generated based on simulations using Zero Forcing shows an increase in value along with an increase in SNR, but has a smaller value compared to channel capacity in theory.

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M. Sana, Ahmed, Amer T. Saeed, and Yaseen Kh. Yaseen. "Investigation on the PAPR performance of odd-bit QAM constellations for DFT spread OFDM systems." Indonesian Journal of Electrical Engineering and Computer Science 21, no. 2 (February 1, 2021): 1005. http://dx.doi.org/10.11591/ijeecs.v21.i2.pp1005-1013.

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Adaptive quadrature amplitude modulation (QAM) is a crucial scheme that enables the modern communication systems to overcome the adverse effects of channel fluctuations and maintain an acceptable spectral efficiency. In order to enhance adaptive modulation even further, adoption of odd-bit QAM constellations alongside even constellations had been suggested to improve the transmission efficiency of adaptive QAM modulation. Hence, odd-bit QAM had been extensively studied, analyzed, and tested by many researchers for various patterns, sizes, and communication systems in terms of bit error rate (BER) and peak to average power ratio (PAPR). However, the PAPR performance of odd-bit QAM constellation with single carrier transmission systems adopted in the uplink of the 4G long term evolution (LTE) standards caught almost no research interest. In this paper, the PAPR performance of both cross and rectangular odd-bit QAM constellations are investigated for DFT-S-OFDM systems. Complementary cumulative distribution functions (CCDFs) and probability density functions (PDFs) curves for PAPR are also obtained. Finally, an equation for PAPR PDF is empirically derived for odd-bit cross QAM based DFT-S-OFDM. The results show that cross odd-bit QAM outperforms the rectangular odd-bit QAM in terms of PAPR by 1.02 dB for 8-QAM and 1.3 dB for 32-QAM. This proves that cross odd-bit QAM is a better choice in terms of PAPR for DFT-S-OFDM systems.

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AL-Rawi, Muhanned. "Data Transmission at 14.4kb/s OVER 32kb/s ADPCM Channel." Technological Engineering 15, no. 2 (December 1, 2018): 27–30. http://dx.doi.org/10.1515/teen-2018-0014.

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Abstract This paper presents new modified QAM modem that operates at data rate of 14.4kb/s to be transmitted over 32kb/s Adaptive Differential Pulse Code Modulation (ADPCM). The purpose of this modified QAM modem is to reduce the nonlinear distortion introduced by ADPCM. The performance of ADPCM is studied considering the standard QAM modem and modified QAM modem with different constellations. The simulation results show that the performance of ADPCM with modified QAM modem is better than its performance with standard QAM modem. Also, the performance with circular constellation is better than rectangular one.

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Ahmad, Husham Jawad. "Performance Evaluation and Simulation of M-Ary Quadrature Amplitude Modulation Schemes with VisSim/Comm Software." Cihan University-Erbil Scientific Journal 3, no. 2 (August 20, 2019): 58–63. http://dx.doi.org/10.24086/cuesj.v3n2y2019.pp58-63.

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M-ary modulation schemes are considered one of widely used digital modulation in practice because of its high efficiency in power and bandwidth. Therefore, this necessity the need to study and evaluate the performance of M-ary schemes using simulation techniques. In this paper, the performance of M-ary modulations schemes M-ary quadrature amplitude modulation (QAM) is considered. Because of its efficiency in power and bandwidth, M-ary QAM (M-QAM) is one of the widely used modulation techniques in practice. Therefore, a need for studying and evaluating the performance of QAM modulation schemes is an important task for designers. In this paper, M-QAM modulation schemes for even number of bits per symbol (16, 62, and 256-QAM) and an odd number of bits per symbol (32- and 128-QAM), over Additive White Gaussian Noise channel, are studied. A VisSim/Comm simulation[1] model for M-QAM is designed. Theoretical and simulation results for bit error ratio (BER) performance of QAM modulation schemes are obtained using VisSim/Comm software. The results are evaluated and compared.

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UJANG, FEBRIZAL, and AINUL YAKIN. "Analisis Perbandingan Kinerja Sistem Radio Over Fiber Modulasi Optik Langsung dan Eksternal." ELKOMIKA: Jurnal Teknik Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronika 11, no. 2 (April 17, 2023): 351. http://dx.doi.org/10.26760/elkomika.v11i2.351.

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ABSTRAKRadio Over Fiber (ROF) adalah sistem komunikasi yang digunakan untuk mentransmisikan sinyal radio frequency (RF) melalui serat optik. Kapasitas dan mobilitas jaringan akses dapat ditingkatkan dengan memanfaatkan sistem ROF. Modulasi sinyal optik dapat dilakukan dengan teknik modulasi optik langsung maupun modulasi optik eksternal. Dalam jurnal ini dilakukan perbandingan kinerja dari kedua teknik modulasi optik tersebut. Input sinyal RF yang digunakan adalah sinyal RF termodulasi 4-QAM, 16-QAM, dan 64-QAM dengan frekuensi 60 GHz. Hasil simulasi menunjukkan bahwa dispersi kromatik menyebabkan terjadinya penurunan daya yang sangat besar pada sinyal RF yang diterima secara berulang. Pada sistem ROF modulasi optik langsung dengan input berupa sinyal RF termodulasi 4-QAM, 16-QAM, dan 64-QAM terjadi penurunan daya pada panjang fiber yang sama yaitu pada Panjang fiber 1 dan 3 km. Pada sistem ROF modulasi optik eksternal terjadi penurunan daya pada titik yang sama yaitu pada pada panjang fiber 1 dan 3 km.Kata kunci: Dispersi, Modulasi Langsung, Modulasi Eksternal, QAM, ROF ABSTRACTRadio Over Fiber (ROF) is a communication system used to transmit radio frequency (RF) signals through optical fiber. The capacity and mobility of access networks can be increased by utilizing ROF systems. Modulation of optical signals can be done with direct optical modulation techniques or external optical modulation. In this journal, the performance of the two optical modulation techniques is compared. The input RF signals used are 4-QAM, 16-QAM, and 64-QAM modulated RF signals with a frequency of 60 GHz. The simulation results show that chromatic dispersion causes a very large power decrease in the received RF signal repeatedly. In the direct optical modulation ROF system with input in the form of 4-QAM, 16-QAM, and 64-QAM modulated RF signals, there is a decrease in power at the same fiber length, namely at 1 and 3 km fiber length. In the external optical modulation ROF system, there is a decrease in power at the same point, namely at a fiber length of 1 and 3 km.Keywords: Dispersion, Direct Modulation, External modulation, QAM, ROF

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Luţă, Alexandru-Daniel, and Paul Bechet. "An Algorithm for Automatic Recogniton of Digital QAM Modulations." International conference KNOWLEDGE-BASED ORGANIZATION 25, no. 3 (June 1, 2019): 36–41. http://dx.doi.org/10.2478/kbo-2019-0114.

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Abstract This paper proposes a new Matlab-developed algorithm for automatic recognition of digital modulations using the constellation of states. Using this technique the automatic distinction between four digital modulation schemes (8-QAM, 16-QAM, 32-QAM and 64-QAM) was made. It has been seen that the efficiency of the algorithm is influenced by the type of modulation, the value of the signal-to-noise ratio and the number of samples. In the case of an AWGN noise channel the simulation results indicated that the value of SNR (signal-to-noise ratio) has a small influence on the recognition rate for lower-order QAM (8-QAM and 16-QAM). The length of the signal may change essentially the recognition rate of this algorithm especially for modulations with a high number of bits per symbol. Consequently, for the 64-QAM modulation in a case of 25dB signal-to-noise ratio the recognition rate is doubled if the sample rate is incresed from 5400 to 80640.

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GOZZELINO, G., D. E. ROMERO TOBAR, N. CHAITIEMWONG, W. HAZELEGER, and R. BEUMER. "Antibacterial Activity of Reactive Quaternary Ammonium Compounds in Solution and in Nonleachable Coatings." Journal of Food Protection 74, no. 12 (December 1, 2011): 2107–12. http://dx.doi.org/10.4315/0362-028x.jfp-11-220.

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Antibacterial polymers suitable for coating applications without leaching of the biocidal component have been obtained by UV copolymerization of acrylic resins with acrylic monomers containing quaternary ammonium moieties. Suitable reactive biocides, based on quaternary ammonium monomers (QAMs), endowed with undecylacryloyl group and alkyl chains with 2 (QAM-C2), 8 (QAM-C8), and 16 (QAM-C16) carbon atoms have been synthesized. Aqueous solutions of QAMs showed biocidal activity against Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes strains both in suspension and adhered to stainless steel surfaces. QAM-C16 and QAM-C8 evidenced higher activity toward bacteria in suspension and on stainless steel, respectively. The QAMs have shown sufficient reactivity to be copolymerized, by UV irradiation, with a commercial urethane acrylic resin for coating. Bioactivity tests, performed on free films of crosslinked coatings containing 1% of copolymerized QAM, have shown an increasing inactivation effect in the order of magnitude L. monocytogenes < E. coli < S. aureus with a maximum activity of the QAM-C8.

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Ni'amah, Khoirun, Muhammad Panji Kusuma Praja, and Yuninda Dwianti Marimbun. "Comparative Analysis of 16-QAM and 64-QAM Modulation in Additive White Gaussian Noise and Rayleigh Fading Channels." CESS (Journal of Computer Engineering, System and Science) 7, no. 1 (December 27, 2021): 90. http://dx.doi.org/10.24114/cess.v7i1.26729.

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This reseach simulates and analyzes paramaters bit error rate (BER) of 16-QAM and 64-QAM modulation on Additive White Gaussian Noise and Rayleigh Fading channels. This research aims to determine 5G modulation with the level of data quality after the transmission process is carried out. The modulation simulation results obtained will be compared with the theoretical bit error rate (BER). The simulation results obtained from the two channel scenarios used are 16-QAM modulation reaching BER 10-4, AWGN channel only requires 15 dB Eb/N0 and for Rayleigh Fading channel it requires 38 dB Eb/N0. The BER theoretical results obtained for the 16-QAM modulation of the AWGN channel have a difference of 3 dB with the simulation results, while for the Rayleigh Fading channel it is 5 dB. Then, the simulation results of 64-QAM modulation AWGN channel to achieve BER 10-4 requires Eb/N0 of 24.6 dB, Rayleigh Fading of 47 dB. The theoretical results of BER obtained for the 64-QAM modulation of the AWGN channel have a difference of 1 dB with the simulation results, while for the Rayleigh Fading channel it is 0.5 dB. In this study, between 16-QAM and 64-QAM 5G modulation is more suitable to use 16-QAM modulation because it requires less power to achieve the desired BER 10-4.

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MUHARRAM, ISNAN, RAMZI ADRIMAN, and NASARUDDIN NASARUDDIN. "Pengaruh Link Relay Terhadap Kinerja Komunikasi Kooperatif Vehicle-to-Vehicle (V2V)." ELKOMIKA: Jurnal Teknik Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronika 10, no. 1 (January 14, 2022): 90. http://dx.doi.org/10.26760/elkomika.v10i1.90.

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ABSTRAKKebutuhan komunikasi bergerak saat ini sangat tinggi, Vehicular Ad-hoc Network (VANET) merupakan metode teknologi telekomunikasi untuk komunikasi bergerak pada kendaraan. Penelitian ini dilakukan untuk mendapatkan metode terbaik dari komunikasi bergerak pada kendaraan dengan mempertimbangkan pengaruh Kecepatan kendaraan dan fading terhadap kinerja jaringan. Metode yang digunakan pada paper ini menggunakan jaringan single-relay yang disimulasikan menggunakan software MATLAB. Parameter kinerjanya adalah Bit Error Rate (BER) dan throughput untuk jaringan sistem komunikasi kooperatif Vehicle to Vehicle (V2V) dengan kondisi link relay Line of Sight (LOS) dan Non Line of Sight (NLOS). Kemudian, modulasi 16-QAM, 32-QAM dan 64-QAM digunakan untuk menguji parameter tersebut. Hasil simulasi menunjukkan bahwa kinerja sistem komunikasi kooperatif V2V dengan modulasi 16-QAM lebih baik dibandingkan 32-QAM dan 64-QAM untuk kondisi LOS dan NLOS. Sehingga usulan penelitian ini dapat menjadi solusi untuk perkembangan sistem komunikasi kooperatif V2V.Kata kunci: VANET, V2V, Link relay, Bit Error Rate (BER), Throughput. ABSTRACTThe need for mobile communication is currently very high; vehicular Ad-hoc Network (VANET) is the telecommunications technology method for mobile communication in vehicles. This research was conducted to obtain the best mobile communication method in vehicles by considering the effect of vehicle speed and fading on network performance. The method used in this paper uses a single-relay network which is simulated using MATLAB software. The performance parameters are Bit Error Rate (BER) and Throughput for the Vehicle to Vehicle (V2V) cooperative communication system network with Line of Sight (LOS) and Non-Line of Sight (NLOS) link relay conditions. Then, 16-QAM, 32-QAM, and 64-QAM modulations were used to test these parameters. The simulation results show that the performance of the V2V cooperative communication system with 16-QAM modulation is better than 32-QAM and 64-QAM for LOS and NLOS conditions so that this research proposal can be a solution for the development of a V2V cooperative communication system.Keywords: VANET, V2V, link relay, Bit Error Rate (BER), Throughput.

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Morais de Oliveira, Flavia Camila, Maria de Lourdes Melo Guedes Alcoforado, Gareguin Markarian, Valdemar Cardoso da Rocha Jr, and Waslon Terllizzie Araújo Lopes. "Combined Polar Codes and 2-12 QAM Applied to 5G Communications." Journal of Communication and Information Systems 38, no. 1 (2023): 120–27. http://dx.doi.org/10.14209/jcis.2023.14.

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The 5th generation of cellular communications systems (5G), standardized by the 3rd Generation Partnership Project (3GPP), uses polar codes in both physical download control channel (PDCCH) and physical download shared channel (PDSCH), combined with some low order modulations, such as QPSK and 16-QAM. Recently, 2-12-QAM modulation was proposed as an energy-efficient scheme when compared to 16-QAM. This article investigates the performance of a communication system using polar codes combined with a 2-12-QAM modulation scheme over channels disturbed by additive white Gaussian noise (AWGN) as well as over channels disturbed simultaneously by Rayleigh fading and AWGN. The 2-12-QAM modulation is compatible with legacy 16-QAM still widely used, and when combined with appropriate error correcting codes produces results that approach the Shannon limit.

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Ali, Ahmed K., and Ergun Erçelebi. "An M-QAM Signal Modulation Recognition Algorithm in AWGN Channel." Scientific Programming 2019 (May 12, 2019): 1–17. http://dx.doi.org/10.1155/2019/6752694.

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Computing the distinct features from input data, before the classification, is a part of complexity to the methods of automatic modulation classification (AMC) which deals with modulation classification and is a pattern recognition problem. However, the algorithms that focus on multilevel quadrature amplitude modulation (M-QAM) which underneath different channel scenarios is well detailed. A search of the literature revealed that few studies were performed on the classification of high-order M-QAM modulation schemes such as 128-QAM, 256-QAM, 512-QAM, and 1024-QAM. This work focuses on the investigation of the powerful capability of the natural logarithmic properties and the possibility of extracting higher order cumulant’s (HOC) features from input data received raw. The HOC signals were extracted under the additive white Gaussian noise (AWGN) channel with four effective parameters which were defined to distinguish the types of modulation from the set: 4-QAM∼1024-QAM. This approach makes the classifier more intelligent and improves the success rate of classification. The simulation results manifest that a very good classification rate is achieved at a low SNR of 5 dB, which was performed under conditions of statistical noisy channel models. This shows the potential of the logarithmic classifier model for the application of M-QAM signal classification. furthermore, most results were promising and showed that the logarithmic classifier works well under both AWGN and different fading channels, as well as it can achieve a reliable recognition rate even at a lower signal-to-noise ratio (less than zero). It can be considered as an integrated automatic modulation classification (AMC) system in order to identify the higher order of M-QAM signals that has a unique logarithmic classifier to represent higher versatility. Hence, it has a superior performance in all previous works in automatic modulation identification systems.

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XU, Chengqian, Xiaoyu CHEN, and Kai LIU. "New Constructions of Perfect 8-QAM+/8-QAM Sequences." IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E97.A, no. 4 (2014): 1012–15. http://dx.doi.org/10.1587/transfun.e97.a.1012.

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Sjödin, Martin, Pontus Johannisson, Jianqiang Li, Erik Agrell, Peter A. Andrekson, and Magnus Karlsson. "Comparison of 128-SP-QAM with PM-16-QAM." Optics Express 20, no. 8 (March 26, 2012): 8356. http://dx.doi.org/10.1364/oe.20.008356.

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Kumar, Arun, Mohit Kumar Sharma, Kanchan Sengar, and Suraj Kumar. "NOMA based CR for QAM-64 and QAM-256." Egyptian Informatics Journal 21, no. 2 (July 2020): 67–71. http://dx.doi.org/10.1016/j.eij.2019.10.004.

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Wongroekdee, Sawitree, Kosin Chaiprathum, Virasit Imtawil, and Puripong Suthisopapan. "LDPC Coded 2^m-ary QAM for Ultra High Speed Communications." Applied Mechanics and Materials 781 (August 2015): 45–48. http://dx.doi.org/10.4028/www.scientific.net/amm.781.45.

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Modern communication systems that employ LDPC codes and QAM modulation can achieve high speed and reliable transmission without bandwidth expansion. In this paper, the performances of LDPC codes with 2m- ary QAM at m>10, which can provide enormous bandwidth efficiency, are studied. Bit error rate performances of various combinations of LDPC codes and order of QAM are provided. From the results, the performance of LDPC coded ultra-high order QAM is excellent making this system very attractive for ultra-high speed communications.

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Aksara, Deschie Tri, Alfredo Bayu Satriya, and Dodi Setiabudi. "ANALISIS PERBANDINGAN BER DAN PAPR DALAM TRANSMISI CITRA PADA SISTEM 4G LTE." Jurnal Arus Elektro Indonesia 6, no. 1 (April 30, 2020): 17. http://dx.doi.org/10.19184/jaei.v6i1.16339.

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Teknologi telekomunikasi saat ini menuntut penggunaan data rate yang tinggi dalam proses pengiriman data. OFDM merupakan teknologi multiplexing yang didasarkan pada penyebaran data yang dimodulasikan pada kecepatan data rendah. OFDM memiliki keunggulan tahan terhadap multipath delay spread, frequency selective fading, serta modulasi dan demodulasi yang efisien. Penelitian ini bertujuan untuk mengetahui karakteristik BER dan PAPR terhadap SNR dan mengetahui perbandingan kinerja teknik modulasi QPSK, 16-QAM dan 64-QAM. Penelitian dijalankan dengan melakukan simulasi pengiriman citra melalui kanal Rayleigh Fading menggunakan modulasi QPSK, 16-QAM, dan 64-QAM. Parameter SNR yang diteliti sebesar 0-16 dB. Hasil simulasi menunjukkan bahwa OFDM memiliki ketahanan noise yang lebih tinggi saat menggunakan modulasi 16-QAM dengan BER = 0 dB saar SNR 10 dB dan rata-rata nilai PAPR yang semakin meningkat dari SNR 0 dB hingga 16 dB.

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Pebriyanti, Cahyani, Nabilah Lestari, Nur Asyiyah, Endah Setyowati, Khanzademma Qeisha Pynda, Daffa' Sami Nasrullah, and Daryan Pratama Alifi. "Studi Komparatif Modulasi M-QAM dan QPSK pada Jaringan 4G-LTE." AVITEC 6, no. 1 (February 1, 2024): 11. http://dx.doi.org/10.28989/avitec.v6i1.2003.

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Kemajuan teknologi telekomunikasi, khususnya jaringan 4G atau LTE (Long Term Evolution), telah mengubah dunia komunikasi seluler secara signifikan. Namun, dengan meningkatnya penggunaan layanan 4G LTE sering kali diikuti oleh gangguan sinyal yang cukup mengganggu. Studi ini menggunakan metode literature review dengan menggali data yang ada sebelumnya, diikuti dengan analisis dan eksplanasi rinci untuk melengkapi penelitian sebelumnya. Penelitian ini berfokus pada berbagai tingkat modulasi, termasuk QPSK, 16-QAM, 64-QAM, dan 256-QAM. Parameter utama yang diamati adalah throughput, yang merupakan ukuran utama untuk mengevaluasi efisiensi teknik pengiriman data dalam berbagai kondisi. Hasilnya menunjukkan bahwa modulasi tingkat tinggi, seperti 256-QAM dan 64-QAM, menunjukkan nilai throughput yang lebih tinggi dibandingkan dengan modulasi QPSK. Diharapkan bahwa penelitian ini akan memberikan gambaran umum tentang hubungan antara modulasi dan teknologi 4G LTE.

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Lin, Chin-Feng, Cheng-Fong Wu, Ching-Lung Hsieh, Shun-Hsyung Chang, Ivan A. Parinov, and Sergey Shevtsov. "Generalized Frequency Division Multiplexing-Based Low-Power Underwater Acoustic Image Transceiver." Sensors 22, no. 1 (December 31, 2021): 313. http://dx.doi.org/10.3390/s22010313.

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In this paper, a low-power underwater acoustic (UWA) image transceiver based on generalized frequency division multiplexing (GFDM) modulation for underwater communication is proposed. The proposed transceiver integrates a low-density parity-check code error protection scheme, adaptive 4-quadrature amplitude modulation (QAM) and 16-QAM strategies, GFDM modulation, and a power assignment mechanism in an UWA image communication environment. The transmission bit error rates (BERs), the peak signal-to-noise ratios (PSNRs) of the received underwater images, and the power-saving ratio (PSR) of the proposed transceiver obtained using 4-QAM and 16-QAM, with perfect channel estimation, and channel estimation errors (CEEs) of 5%, 10%, and 20% were simulated. The PSNR of the received underwater image is 44.46 dB when using 4-QAM with a CEE of 10%. In contrast, PSNR is 48.79 dB when using 16-QAM with a CEE of 10%. When BER is 10−4, the received UW images have high PSNR values and high resolutions, indicating that the proposed transceiver is suitable for underwater image sensor signal transmission.

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Zhang, Qianwu, Hai Zhou, Yuntong Jiang, Bingyao Cao, Yingchun Li, Yingxiong Song, Jian Chen, Junjie Zhang, and Min Wang. "A Simple Joint Modulation Format Identification and OSNR Monitoring Scheme for IMDD OOFDM Transceivers Using K-Nearest Neighbor Algorithm." Applied Sciences 9, no. 18 (September 17, 2019): 3892. http://dx.doi.org/10.3390/app9183892.

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In this study, a joint modulation format identification and optical signal-to-noise ratio (OSNR) monitoring algorithm is proposed and experimentally demonstrated using the k-nearest neighbor algorithm for intensity modulation and direct detection (IMDD) orthogonal frequency division multiplexing (OFDM) systems. A modified amplitude histogram of received signal is employed to serve as the classification feature to simplify the computation. Experimental results show that five common quadrature amplitude modulation (QAM) modulation formats, including 4-QAM, 16-QAM, 32-QAM, 64-QAM and 128-QAM, can be identified under 100% accurate estimation at the received optical power of −11 dBm. Robustness of the proposed scheme to constellation rotation is also experimentally assessed. At the same time, system OSNR monitoring also can be achieved and the average prediction mean square error (MSE) is 0.69 dB2, which is similar to that using an artificial neural network. Computational complexity assessment demonstrated that similar performance but less computing resource consumption can be achieved by using the proposed scheme rather than the artificial neural network-based scheme.

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Wu, Mingwei, Yong Huat Chew, and Tjeng Thiang Tjhung. "Comparison of Quotiently Coherent QAM, Differentially Coherent QAM and Coherent QAM over Rayleigh Flat Fading Channel." International Journal on Wireless & Optical Communications 01, no. 01 (June 2003): 41–52. http://dx.doi.org/10.1142/s0219799503000094.

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Fowdur, Tulsi Pawan, and Madhavsingh Indoonundon. "A Hybrid Statistical and Prioritised Unequal Error Protection Scheme for IEEE 802.11n LDPC Codes." International journal of electrical and computer engineering systems 8, no. 1 (2017): 1–9. http://dx.doi.org/10.32985/ijeces.8.1.1.

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The combination of powerful error correcting codes such as (LDPC) codes and Quadrature Amplitude Modulation (QAM) has been widely deployed in wireless communication standards such as the IEEE 802.11n and DVB-T2. Recently, several Unequal Error Protection schemes which exploit non-uniform degree distribution of bit nodes in irregular LDPC codes have been proposed. In parallel, schemes that exploit the inherent UEP characteristics of the QAM constellation have also been developed. In this paper, a hybrid UEP scheme is proposed for LDPC codes with QAM. The scheme uses statistical distribution of source symbols to map the systematic bits of the LDPC encoded symbols to the QAM constellation. Essentially, systematic symbols having highest probabilities of occurrence are mapped onto the low power region of the QAM constellation and those with a low probability of occurrence are mapped onto the high power region. The decrease in overall transmission power allows for an increased spacing between the QAM constellation points. Additionally, the scheme uses the distribution of the bit node degree of the LDPC code-word to map the parity bits having the highest degree onto prioritised QAM constellation points. Simulations with the IEEE 802.11n LDPC codes revealed that the proposed scheme can provide gains of up to 0.91 dB in Eb/No compared with other UEP schemes for a range of Bit Error Rate (BER) values

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Indoonundon, Madhavsingh, and Tulsi Fowdur. "An unequal error protection scheme for non-binary LDPC using statistical QAM and prioritized mapping." Serbian Journal of Electrical Engineering 15, no. 3 (2018): 301–17. http://dx.doi.org/10.2298/sjee1803301i.

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Low Density Parity Check (LDPC) codes are among the most popular channel codes used nowadays because of their ability to achieve near channel capacity performances. However, with the ever-increasing demand for reliable transmission of data at higher data rates, there is a need to narrow down the gap between the performance of LDPC codes and the channel capacity. LDPC codes and Quadrature Amplitude Modulation (QAM) have been widely deployed in wireless communication standards such as the IEEE 802.11n and Digital Video Broadcasting-Second Generation Terrestrial (DVB-T2). Recently, several Unequal Error Protection (UEP) schemes have been used to enhance the performance of LDPC codes. In this paper an UEP scheme is proposed for Non- Binary LDPC codes with QAM. The scheme uses the statistical distribution of the source symbols to obtain a more efficient statistical QAM constellation. Additionally, it uses the degree distribution of the nodes of the LDPC codeword to achieve prioritized QAM mapping. Simulations revealed that the proposed scheme can provide Eb/N0 gains of up to 0.78 dB and 1.24 dB with 16-QAM and 64-QAM respectively in the range BER?10-2.

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Ramadhan, Gilang, Alfredo Bayu Satriya, and Dodi Setiabudi. "ANALISA KINERJA SISTEM SINGLE CARRIER-FREQUENCY DIVISION MULTIPLE ACCESS UNTUK TRANSMISI CITRA." Jurnal Arus Elektro Indonesia 6, no. 1 (April 30, 2020): 12. http://dx.doi.org/10.19184/jaei.v6i1.16397.

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Teknologi Long Term Evolution (LTE) menggunakan 2 sistem pada sisi yang berbeda, yaitu pada sisi downlink dengan OFDMA dan SC-FDMA pada sisi uplink. SC-FDMA memiliki kelebihan pada sisi efisiensi daya dibandingkan dengan OFDMA. Berdasarkan 3GPP Release 8, modulasi LTE meliputi QPSK, 16-QAM dan 64QAM. Penelitian ini bertujuan untuk mengetahui karakteristik BER dan PAPR terhadap SNR, menganalisis perbandingan BER dan PAPR terhadap SNR pada sistem SC-FDMA, dan mengetahui perbandingan kinerja teknik modulasi QPSK, 16-QAM dan 64-QAM. Hasil kinerja sistem melewati kanal yang berdistribusi Rayleigh. Penelitian dijalankan dengan melakukan simulasi pengiriman citra melalui kanal Rayleigh Fading menggunakan modulasi QPSK, 16-QAM, dan 64-QAM. Parameter SNR yang diteliti sebesar 0-16 dB. Hasil simulasi menunjukkan bahwa SC-FDMA memiliki ketahanan noise yang lebih tinggi saat menggunakan modulasi QPSK dengan BER = 0 dB saat SNR = 13 dB dan PAPR yang stabil di angka 0,9 dB.

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Maharani, Tamara, Muhammad Agus Zainuddin, and Sritrusta Sukaridhoto. "PENGUKURAN PSNR PADA TRANSMISI VIDEO DI KANAL TERAHERTZ MENGGUNAKAN QAM MODULATION." KLIK - KUMPULAN JURNAL ILMU KOMPUTER 7, no. 2 (June 28, 2020): 154. http://dx.doi.org/10.20527/klik.v7i2.319.

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In the current era of communication has various challenges that include the intensity of information exchange more often, the amount of information carried and the speed in exchanging information. Communication is not only in the form of text and sound but also in the form of pictures and videos. This study tries to use digital data in the form of video with the aim of providing a view of the PSNR measurement simulation. The method used is modulation of QAM 64, 256, 1024 and 4096 through terahertz channels (0.1-10 THz). Simulation results show that in QAM 64 the PSNR value is 35.2 dB to 36.6 dB. The PSNR value decreases as the M-ary increases. PSNR at 256 QAM ranges from 25.9 to 26.5 dB. PSNR in QAM 1024 is stable at magnitude 16.3 to 16.5. Whereas PSNR in QAM 4096 ranged from 15.0 to 15.25. From this study shows the greater the value of PSNR, the quality of information sent is increasingly similar. In addition, the higher the M-ary, the data carried will also be large so as to speed up the transmission time.Keywords: Terahertz, QAM, PSNR, Video, Simulation Di era saat ini komunikasi memiliki berbagai tantangan yang meliputi intesitas pertukaran informasi yang lebih sering, besarnya informasi yang dibawa dan kecepatan dalam bertukar informasi. Komunikasi tidak hanya berupa text dan suara namun juga berupa gambar dan video. Penelitian ini mencoba menggunakan data digital berupa video dengan tujuan memberikan pandangan tentang simulasi pengukuran PSNR. Metode digunakan yaitu modulasi QAM 64, 256, 1024 dan 4096 melalui kanal terahertz (0.1-10 THz). Hasil simulasi menunjukkan pada QAM 64 nilai PSNR sebesar 35.2 dB hingga 36.6 dB. Nilai PSNR menurun seiring bertambahnya M-ary. PSNR pada QAM 256 di rentang 25.9 hingga 26.5 dB. PSNR pada QAM 1024 stabil di besaran 16.3 sampai 16.5. Sedangkan PSNR pada QAM 4096 di rentang 15.0 hingga 15.25. Dari penelitian ini menunjukkan semakin besar nilai PSNR maka kualitas informasi yang dikirimkan semakin mirip. Selain itu semakin tinggi M-ary maka data yang dibawa pun juga ikut besar sehingga mempercepat waktu transimisi. Kata kunci: Terahertz, QAM,PSNR, Video, Simulasi

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Chandra, Dikky, Fauzi Aditia Rahmat, Siska Aulia, Firdaus -, and Andre Febrian Kasmar. "Effect of Modulation on Throughput of 4G LTE Network Frequency 1800 MHz." International Journal of Advanced Science Computing and Engineering 5, no. 1 (April 10, 2023): 44–53. http://dx.doi.org/10.62527/ijasce.5.1.121.

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In the development of 4G LTE technology, network speed (Throughput) in several regions has increased or decreased. Network speed (Throughput) certainly cannot be separated from Modulation.Â In modulation there are several kinds of modulation schemes, be it QPSK modulation, 16 QAM modulation, and 64 QAM modulation. The modulation scheme is instrumental in increasing throughput. Based on several previous studies, they only check the Throughput parameters without doing a more in-depth analysis of the modulation scheme which also plays a very important role in network speed (Throughput). For this reason, it is necessary to carry out an analysis related to the effect of modulation on the throughput value. To find out the effect of modulation on throughput, it is necessary to take data in the field, the method used is the Drive Test method. Based on the results of the Drive Test, QPSK modulation has a Throughput value of 5.247.4 Kbps, modulation of 16 QAM has a Throughput value of 27.293.9 Kbps and modulation of 64 QAM has a Throughput value of 65.275.1 Kbps. Based on the data in the field and in terms of calculations, the modulation that most affects the throughput value is the modulation of 64 QAM. Modulating 64 QAM having 64 symbols where each symbol consists of 6 bits will make the data rate at throughput higher. This also applies to the use of modulation of 16 QAM (16 symbols with 4 bits) and QPSK (4 symbols with 2 bits).

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Ari Endang Jayati and Budiani Destyningtias. "Perbandingan Kinerja Generalized Frequency Division Multiplexing Menggunakan Modulasi QAM dan Offset QAM." Jurnal Nasional Teknik Elektro dan Teknologi Informasi 12, no. 1 (February 1, 2023): 1–7. http://dx.doi.org/10.22146/jnteti.v12i1.2548.

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Generalized frequency division multiplexing (GFDM) merupakan sistem multicarrier masa datang yang bersifat nonortogonal. GFDM merupakan teknik transmisi data berbentuk blok yang setiap subcarrier-nya dibentuk dari pulsa berbentuk nonrectangular. Penerapan quadrature amplitude modulation (QAM) mapping untuk GFDM sangat baik karena meningkatkan efisiensi spektrum. QAM juga memiliki keterbatasan, yaitu meningkatnya kompleksitas ketika diimplementasikan. Selain itu, inter-carrier interference (ICI) juga masih ada dan sangat berpengaruh terhadap sistem. Untuk melakukan mitigasi terhadap kelemahan itu, digunakan teknik offset QAM (OQAM) mapping. Kelebihan GFDM/OQAM dibandingkan GFDM/QAM adalah komponen quadrature dan in-phase pada modulasi OQAM tidak mengalami pergeseran pada slot waktu yang sama, out of band (OOB) yang rendah, pesat data yang tinggi, dan bebas ICI. Makalah ini membandingkan dua skenario, yaitu sistem GFDM/OQAM dan sistem GFDM/QAM. Penelitian ini menganalisis kinerja bit error rate (BER) jika sinyal dilewatkan saluran additive white Gaussian noise (AWGN) dan saluran Rayleigh. Hasil simulasi menunjukkan bahwa GFDM/OQAM mempunyai kinerja lebih bagus. Hasil simulasi menunjukkan bahwa agar mendapatkan BER 10-2, terjadi penurunan nilai rasio energi per bit terhadap daya derau ( ) sebanyak 8 dB pada modulasi QAM ke OQAM ketika dilewatkan kanal AWGN. Sementara itu, ketika dilewatkan kanal Rayleigh, untuk mendapatkan nilai BER 10-2, terjadi penurunan nilai sebanyak 9 dB pada modulasi QAM ke OQAM. Selain itu, penelitian ini juga telah berhasil menyelidiki kinerja kedua sistem untuk parameter diagram konstelasi dan spektrum sinyal. Penelitian ini berhasil mendapatkan acuan nilai roll-off factor yang dapat digunakan pada penerapan sistem GFDM/OQAM dengan hasil kinerja terbaik yaitu 0,3. Faktor nilai roll-off factor sangat memengaruhi kinerja pada sistem GFDM.

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PAMBUDI, AFIEF DIAS, SUHARTONO TJONDRONEGORO, and HEROE WIJANTO. "Deteksi Automatis Skema Modulasi Sinyal OFDM menggunakan Ciri Statistik dan Klasifikasi PSO." ELKOMIKA: Jurnal Teknik Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronika 3, no. 2 (July 1, 2015): 133. http://dx.doi.org/10.26760/elkomika.v3i2.133.

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ABSTRAKPengenalan format modulasi dari sinyal yang dideteksi merupakan salah satu bahasan penting pada sistem intelligent receiver yang digunakan untuk aplikasi di bidang militer maupun komersial. Oleh karena itu, pada penelitian ini dilakukan klasifikasi skema modulasi pada sinyal OFDM yaitu QPSK, 16-QAM dan 64-QAM. Sinyal OFDM tersebut disimulasikan melewati kanal frequency selective fading dan additive white gaussian noise. Sistem klasifikasi yang dibuat menggunakan ekstraksi ciri statistik dan pengklasifikasi berupa diagram keputusan dengan threshold yang dioptimasi menggunakan algoritma particle swarm optimization (PSO). Pada proses klasifikasi ditambahkan sistem voting dengan skenario penggunaan jumlah simbol OFDM sebanyak 1, 5, 10, 15 dan 20. Hasil akurasi klasifikasi yang optimum didapatkan pada penggunaan lima simbol OFDM yaitu 100 %, 99 %, 96 % untuk klasifikasi QPSK, 16-QAM, 64-QAM pada minimum SNR receiver standar WiMAX IEEE 802.16e.Kata kunci: klasifikasi skema modulasi OFDM, ciri statistik, PSO.ABSTRACTModulation recognition of the detected signal is one of important topics on intelligent receiver system used for military and commercial applications. (Therefore) This research explored the classifications of the OFDM signal modulation scheme namely QPSK, 16-QAM and 64-QAM. The OFDM signal was simulated to pass through frequency selective fading channel and additive white gaussian noise. The classification system was developed using statistical feature extraction with a decision diagrams (tree diagram) as a classifier optimized by PSO algorithm. The increasing number of OFDM symbols in the classification process that applied a voting system improved the accuracy of the classification of each modulation scheme. The optimum accuracy of the classification had been obtained when five OFDM symbols were applied in the classification scenario. The accuracy was 100% for QPSK classification, 99 % for 16-QAM classification and 96 % for 64-QAM classification on the minimum SNR accepted by the receiver of a system that applied a standard WiMax IEEE 802.16e.Keywords: classification modulation schemes OFDM, statistical characteristics, PSO.

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Yu, Wei, Fusheng Zhu, Jun Wu, Rui Wang, Haoqi Ren, and Zhifeng Zhang. "HARQ-Chaotic: Analog Chaotic Code Applied in HARQ Scheme of Wireless Communication System." Wireless Communications and Mobile Computing 2019 (April 24, 2019): 1–13. http://dx.doi.org/10.1155/2019/3728127.

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This paper proposes a novel symbol-level combining hybrid automatic repeat request (HARQ) scheme based on analog chaotic code and named HARQ-Chaotic. The transmitter of HARQ-Chaotic adopts analog chaotic code to encode Quadrature Amplitude Modulation (QAM) symbols of retransmission packets to combat fading and noise. As the analog chaotic code can only handle sources with amplitudes in the range of [-0.5, 0.5], QAM symbols must be scaled into this range. We derived the optimal scaling factor through theoretical analysis. A joint algorithm combining with novel soft chaotic decoder and novel soft QAM demapper is proposed for the receiver to enhance the performance of the whole communication system. We implemented HARQ-Chaotic with LDPC codes and 16-QAM/64-QAM to carry out simulations in both AWGN channels and multipath fading channels. Massive simulation results demonstrate that the proposed HARQ-Chaotic has 1dB-4dB gain over traditional HARQ-Chase combining (HARQ-CC) scheme in block error rate (BLER) performance.

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Eska, Andrita Ceriana. "Propagation of Mobile Communication with Tree Obstacle used OFDM-QAM at 10 GHz." JURNAL INFOTEL 11, no. 3 (September 30, 2019): 88–92. http://dx.doi.org/10.20895/infotel.v11i3.439.

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This research focused about mobile communication systems at line communication of road. Frequency communication was used 10 GHz. The tree was obstacle at every node of line communication. That communication was modeled with single diffraction. Single knife edge was used for that diffraction model. The communication transmission that used was Orthogonal Frequency Division Multiplexing. The modulation variation that used was consisted of 16 QAM and 64 QAM. Analysis that used was consisted of modulation variation, transmitter power variation, and coverage area variation. The result showed that SNR was decreased when transmitter power was increased, the value BER 64 QAM lower than BER 16 QAM, and percentage of coverage area that obtained was around 96%.

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Wadhwa, Vishwanath, and Dr Mansi Jhamb. "Design Implementation and Performance Analysis of M-QAM and PAM-n Signalling Schemes." International Journal for Research in Applied Science and Engineering Technology 11, no. 7 (July 31, 2023): 938–44. http://dx.doi.org/10.22214/ijraset.2023.54772.

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Abstract: Two circuits have been simulated in the Optisystem 20 software. One circuit has M-QAM and the other has PAM-n. Both the circuits have been compared on the basis of Bits per symbol, signal power,Noise power, etc. The total power and noise power havebeen calculated in the electrical power meter visualizer.In both the circuits, PRBS generator is used to generate the sequence of the bits. In M-QAM,return to zero pulse generator is used and in PAM-n notreturn to zero pulse generator is used. The full width pulse is also known as NRZ (not return to zero) and halfwidth pulse is also known as RZ (return to zero). The main objective of the simulation is to get perfect Eye diagram in the Eye Diagram Anaylzer. The parametriccomparison of different types of QAM have also be doneon the basis of number of samples, sequence length, samples per bit and output power in dBm andcomparison is done by state of art. In the final result, itwill be concluded that M-QAM performs much better than the PAM-n as it is capable of transferring higher data rates. The different types of M-QAM and PAM-n eye diagrams have been plotted like 16-QAM, 64-QAMand PAM-3.

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Laroche, Dominique, Sylvie Chollet-Martin, Pierre Léturgie, Laure Malzac, Marie-Claude Vergnaud, Catherine Neukirch, Lennart Venemalm, Jean-Louis Guéant, and Pascale Nicaise Roland. "Evaluation of a New Routine Diagnostic Test for Immunoglobulin E Sensitization to Neuromuscular Blocking Agents." Anesthesiology 114, no. 1 (January 1, 2011): 91–97. http://dx.doi.org/10.1097/aln.0b013e31820164d2.

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Background Neuromuscular blocking agents (NMBA) are responsible for most immediate hypersensitivity reactions during anesthesia, as a result of the presence of a quaternary ammonium ion. The aim of this study was to evaluate the diagnostic performance of a commercial immunoglobulin E (IgE) test (quaternary ammonium morphine [QAM]) for diagnosing sensitivity to NMBA. Methods We tested 168 patients exposed to NMBAs during anesthesia. Of those patients, 54 had an uneventful procedure and 114 had immediate hypersensitivity reactions, and 57 patients had positive skin tests to the administered NMBA, whereas 57 had negative skin tests. Specific IgE concentrations determined with the QAM method based on a morphine solid phase were compared with those obtained with a recommended experimental method with a choline solid phase. Results For the QAM test, a 0.35 kUA/l positivity cutoff was chosen from the receiver operating characteristics curve. QAM-specific IgE was found in 84.2% of skin test-positive reactors (80.7% with the recommended method; no significant difference), and binding was inhibited by the culprit NMBA in 80% of cases. The frequency of QAM-specific IgE positivity was significantly higher in skin test-negative reactors (24.6%) than in controls (9.3%), suggesting NMBA sensitivity. Conclusion Sensitivity of the QAM test (84.2%), together with its simplicity and suitability for routine laboratory use, makes it a valuable tool, in conjunction with skin tests, for diagnosing NMBA sensitivity in patients who react after NMBA injection. The QAM test is of particular interest when skin tests are not available or not reliable or give results poorly compatible with mediator release or clinical features.

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Zeng, Fan Xin, Zhen Yu Zhang, and Lin Jie Qian. "Mappings from Binary Variables to QAM Symbols and Improvement of Peak Envelope Power of OFDM Systems." Applied Mechanics and Materials 644-650 (September 2014): 4205–9. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.4205.

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This paper establishes a mapping relationship from independent binary variables to QAM symbols. By these proposed mappings square QAM constellation can be produced by binary signals rather than quaternary signals, which is advantageous to operation of those apparatuses driven only by binary signals. As one of applications of these presented mappings, we give an example to verify improvement of upper bounds of peak envelope power in an OFDM communication system employing QAM complementary sequences.

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Yadav, R. Meghana. "TURBO Coded OFDM Improves BER Performance Evaluation for Digital Video Broadcasting." International Journal for Research in Applied Science and Engineering Technology 9, no. 9 (September 30, 2021): 1950–54. http://dx.doi.org/10.22214/ijraset.2021.38220.

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Abstract: Turbo coded Orthogonal Frequency Division Multiplexing (OFDM) is attractive technique for high data rate in wireless communication applications, mobile communications (4G) and Wireless Metropolitan Area Networks (WMAN) and Digital Video Broadcasting (DVB). The performance of TURBO Coded 16 QAM and 64 QAM schemes with OFDM for high speed data rate applications is compared which is used in digital video broadcasting. BER analysis is used to assess the system's performance. Due to the high data rate of 64 QAM, attaining BER of ૚૙ି૝ requires Eb/No of 0.9 dB in 16QAM, whereas obtaining BER of ૚૙ି૝ requires 0.17 dB in 64QAM. By using OFDM removes Inter Symbol Interference (ISI) and Adjacent Channel Interference (ACI). Keywords: Wireless communication, mobile communication, OFDM, QAM, TURBO Encoding

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Sun, Qiu Dong, Zheng Guo Liu, Wen Xin Ma, and Jiang Wei Huang. "The Equivalent Proving of Two Typical Vector Composing PM Circuits and their Characteristic Analysis." Advanced Materials Research 298 (July 2011): 193–96. http://dx.doi.org/10.4028/www.scientific.net/amr.298.193.

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PM, Vector Composing, Armstrong PM, QAM-based PM, Equivalent Analysis Abstract. Both the Armstrong phase modulation (PM) and QAM-based PM are typical vector composing circuits in the course “Radio Frequency Circuits”. Due to having innate defects of nonlinear phase distortion and parasitical AM, the characteristics of Armstrong PM are not good unless the modulation exponent is small enough. Therefore, the Armstrong PM is an approximate circuit. The QAM- based PM is a quite different circuit from the Armstrong PM, and its defects are not given in general teaching material. The equivalence of two circuits is proved in this paper by mathematical method. So, the QAM-based PM has same pros and cons with Armstrong PM and can be replaced with the latter completely.

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Wang, Jingjing, Na Li, Wei Shi, Yangyang Ma, Xiulong Liang, and Xinli Dong. "Capacity of 60 GHz Wireless Communications Based on QAM." Journal of Applied Mathematics 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/815617.

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With apparent advantages of the several GHz license-free spectrums, 10 W maximum transmit power, and so forth, 60 GHz wireless communication technology has become the first choice for Gbps level short-range wireless communications. This paper researches 60 GHz wireless communications over the additive white Gaussian noise channel. Channel capacity with quadrature amplitude modulation (QAM) is investigated for the unlicensed 59–64 GHz radio spectrum set aside by FCC. Moreover, the capacity with QAM is compared to that with phase shift keying (PSK). It is shown that QAM is capable of providing Gbps data rate and outperforms PSK especially when the modulation order is large. The results prove that QAM is an attractive scheme for 60 GHz wireless communications.

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Amillia, Fitri. "Analisis Kinerja Transmisi Citra Melalui Kanal Mobile To Mobile Pada Sistem Orthogonal Frequency Division Multiplexing (OFDM)." Jurnal Sains dan Teknologi Industri 15, no. 2 (June 23, 2018): 131. http://dx.doi.org/10.24014/sitekin.v15i2.5107.

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ABSTRAK Long Term Evolution (LTE) merupakan teknologi nirkabel generasi keempat (4G) memberikan layanan aplikasi multimedia berupa gambar, video dan audio berkualitas tinggi dan kecepatan internet yang tinggi menggunakan teknik transmisi Orthogonal Frequency Division Multiplexing (OFDM). Pada sistem ini menggunakan kanal mobile to mobile, dimana pemancar dan penerima serta entitas jaringan selalu bergerak. Pergerakan pengguna atau obyek di sekitarnya menyebabkan terjadinya pergeseran frekuensi (Doppler shift) yang dapat mempengaruhi kinerja sistem komunikasi. Dengan adanya permasalahan tersebut perlu dilakukan penelitian analisis kinerja transmisi citra melalui kanal mobile to mobile pada sistem OFDM. Hasil perbandingan transmisi masing-masing citra yang berbeda ukuran dalam pixel yang melalui kanal mobile to mobile menggunakan teknik modulasi 4 QAM lebih cepat mendekati nilai standard BER sebesar 10-3 daripada teknik modulasi 16 QAM. Sistem kinerja transmisi citra pada teknik modulasi 4 QAM menunjukkan kinerja transmisi lebih baik disebabkan rendahnya nilai rata-rata Eb/No 16.61 dB mampu memberikan persentase error yang cukup kecil dari pada menggunakan teknik modulasi 16 QAM nilai rata-rata Eb/No yaitu 25.71 dB. Kata Kunci: OFDM, Citra, Transmisi, kanal mobile to mobile, QAM

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Wang, Hsiao-Chi, Tung-Lin Liu, Yuan-Wei Wu, and Hsi-Pin Ma. "A Power-Efficient Soft-Output Detector for Spatial-Multiplexing MIMO Communications." Journal of Electrical and Computer Engineering 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/938490.

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VLSI implementation of a configurable power-efficient MIMO detector is proposed to support4×4spatial multiplexing and modulation from QPSK to 64-QAM. A novel tree search algorithm is proposed to enable the detector to provide soft outputs and to be implemented in parallel and pipelined hardware architecture. The frame error rate (FER) of the detector approaches the quasi-optimal sphere decoder, with 0.5-dB degradation. Moreover, the proposed detector can operate at the optimal voltage under different configurations and detect/recover timing error at run time by a novel adaptive voltage scaling technique with double sampling circuitry. The proposed detector, using TSMC 0.18 μm single-poly six-metal CMOS process with a core area of1.17×1.17 mm2, provides fixed throughput of 45 Mbps in 64-QAM configuration, 120 Mbps in 16-QAM configuration, and 60 Mbps in QPSK configuration. The normalized power efficiency of the design for 64-QAM and 16-QAM configurations is 1.56 Mbps/mW and 2.53 Mbps/mW, respectively. Compared with the conservative margin-based design, the proposed design achieves a 48.8% power saving.

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Fauzan, Rafi Ardhan, and Theophilus Wellem. "SIMULASI SKEMA UNIVERSAL FILTERED MULTI-CARRIER (UFMC) PADA SISTEM KOMUNIKASI DIGITAL." Jurnal Indonesia : Manajemen Informatika dan Komunikasi 4, no. 3 (September 10, 2023): 1380–88. http://dx.doi.org/10.35870/jimik.v4i3.340.

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Universal Filtered Multi-Carrier (UFMC) is a multi-carrier modulation scheme that is an alternative to the Orthogonal Frequency Division Multiplexing (OFDM) scheme currently used in 4G communication systems and wireless local area networks (WLAN). The weakness of OFDM lies in the high peak-to-average power ratio (PAPR) value and out-of-band (OOB) emission which can cause interference between carriers. UFMC is one of the schemes used to overcome the weaknesses of OFDM. This research aims to study the performance of UFMC for data transmission on AWGN channel with 256-QAM, 1024-QAM, and 4096-QAM modulation. In addition, 256-point, 512-point, and 1024-point FFTs were also used to see the effect on the achievable bit error rate (BER) and PAPR value. The simulation results show that for all simulated FFT sizes and QAM values, 256-QAM produces the lowest BER value. Using a 1024-point FFT, a BER of 10-3 can be achieved with an SNR of 20 dB. The lowest PAPR value obtained in the simulation is 7.1891 dB.

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Gao, Xiao Peng, Si Yuan Wang, and Han Wan. "Accelerate Demodulation of Quadrature Amplitude Modulation Using GPU." Applied Mechanics and Materials 325-326 (June 2013): 907–11. http://dx.doi.org/10.4028/www.scientific.net/amm.325-326.907.

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Quadrature amplitude modulation (QAM) is widely used in communication systems. The traditional QAM demodulation method was implemented in hardware. This paper proposes a demodulation algorithm using GPU. The GPU algorithm is easier to add new features than hardware implementation and reaches 57x speed up compared with the serial algorithm on CPU. It is shown that the QAM demodulation algorithm gained significant performance increase due to the natural parallism of the GPU, using Compute Unified Device Architecture (CUDA).

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Anthony Prathap, Joseph, T. S.Anandhi, K. Ramash Kumar, and B. Srikanth. "Performance evaluation and analysis of 64-quadrature amplitude modulator using Xilinx Spartan FPGA." International Journal of Engineering & Technology 7, no. 2.8 (March 19, 2018): 570. http://dx.doi.org/10.14419/ijet.v7i2.8.10523.

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This paper proposes the design of 64-Quadrature Amplitude Modulation using the Very High Speed Integrated Circuit Hardware Description Language (VHDL) coding and XILINX SPARTAN Field Programmable Gate Array (FPGA) real-time implementation for validation. QAM is used in modern digital communication applications like set-top box, satellite TV, wireless and cellular technology etc. In this paper, 64-QAM is implemented and compared with three different XILINX SPARTAN FPGA devices say 3A DSP, 3E and 6E. The power, current and thermal parameters are performed and compared. The power consumed for the design of 64 QAM using the Xilinx SPARTAN 6E FPGA device is 0.014W and 15.9 C/W of Effective TJA for the XILINX SPARTAN 3A DSP FPGA. The device utilization of the 64-QAM design using the XILINX SPARTAN 3A DSP is low.

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Pamungkas, Wahyu, Anggun Fitrian Isnawati, and Adi Kurniawan. "Modulasi Digital Menggunakan Matlab." JURNAL INFOTEL - Informatika Telekomunikasi Elektronika 4, no. 2 (November 10, 2012): 1. http://dx.doi.org/10.20895/infotel.v4i2.102.

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In telecommunication systems, the determination of the modulation system is an important method in the process of sending information from transmitter to receiver. In the simulation that is done using QPSK modulation system (Quadrature Phase Shift Keying), 8-QAM (Quadrature Amplitude Modulation), 16-QAM (16-Quadrature Amplitude Modulation) that uses AWGN (Additive White Gaussian Noise) channel in the transmission system uses MATLAB software. The execution of the simulation is aimed to describe how the characteristics of the waveform of each block of the modulator, to add noise in the AWGN channel and demodulator. Performance of modulation system testing is used BER (bit error ratio) method. Looking of the faults of comparison bits results of before and after the transmitted bits by using Monte Carlo simulation model. Testing on this simulation using the input data as much as 10.000 data symbols randomly and the level of Eb/No that is various for each modulation used. Performance results BER with the level of Eb / No at 1 dB of the simulated system modulation on the BER values obtained for QPSK 0.0570, 8-QAM at 0.1085 while the 16-QAM at 0.1582 and then the performance of QPSK modulation is the best. If the Eb / No is increased to 8 dB then the becomes BER QPSK smaller modulation is equal to 0.00035, the 8-QAM BER obtained at 0.0076, while the 16-QAM modulation to be 0.0139

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ZENG, Fanxin. "Comments on “New Constructions of Perfect 8-QAM+/8-QAM Sequences”." IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences E98.A, no. 6 (2015): 1334–38. http://dx.doi.org/10.1587/transfun.e98.a.1334.

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Chen, Chia-Yi, Po-Yi Wu, Hai-Han Lu, Ying-Pyng Lin, Tai-Wei Jhang, and Cheng-Ling Ying. "Hybrid lightwave subcarrier CATV/16-QAM/16-QAM OFDM transmission system." Optics Letters 38, no. 22 (November 4, 2013): 4538. http://dx.doi.org/10.1364/ol.38.004538.

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Maeda, K., K. Utsumi, and K. Fujito. "Error statistic of QAM channel in AM/QAM hybrid optical transmission." IEEE Photonics Technology Letters 8, no. 10 (October 1996): 1403–5. http://dx.doi.org/10.1109/68.536669.

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Ahn, Seongjin, and Dongweon Yoon. "Circular $\theta$ -QAM: A Circle-Shaped QAM for Higher-Order Modulation." IEEE Access 7 (2019): 149005–12. http://dx.doi.org/10.1109/access.2019.2946339.

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Lv, Xin-Rong, Youming Li, and Yu-Cheng He. "Efficient Impulsive Noise Mitigation for OFDM Systems Using the Alternating Direction Method of Multipliers." Mathematical Problems in Engineering 2018 (June 7, 2018): 1–11. http://dx.doi.org/10.1155/2018/4968682.

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An efficient impulsive noise estimation algorithm based on alternating direction method of multipliers (ADMM) is proposed for OFDM systems using quadrature amplitude modulation (QAM). Firstly, we adopt the compressed sensing (CS) method based on the l1-norm optimization to estimate impulsive noise. Instead of the conventional methods that exploit only the received signal in null tones as constraint, we add the received signal of data tones and QAM constellations as constraints. Then a relaxation approach is introduced to convert the discrete constellations to the convex box constraints. After that a linear programming is used to solve the optimization problem. Finally, a framework of ADMM is developed to solve the problem in order to reduce the computation complexity. Simulation results for 4-QAM and 16-QAM demonstrate the practical advantages of the proposed algorithm over the other algorithms in bit error rate performance gains.

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Dr. Atul Suryavanshi. "Optimized Adaptive Huffmann Coding For Paper Reduction in OFDM Systems." International Journal of New Practices in Management and Engineering 2, no. 04 (December 31, 2013): 13–18. http://dx.doi.org/10.17762/ijnpme.v2i04.23.

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The main defect of OFDM systems is its high peak-to-average power ratio (PAPR). To decrease PAPR, Adaptive Huffman coding is essential. Encoding is transferred by two encoding techniques Huffman coding and Adaptive Huffman coding at the transmitter side. Mapping is done by QAM 16 and PSK 16.The PAPR results of Huffman and adaptive Huffman coding with QAM 16 and PSK 16 is compared. Simulation results shows that the Adaptive Huffman coding along with QAM 16 produces fruitful results in comparison with Huffman coding and adaptive Huffman coding with PSK 16.

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Yang, Zhuwen, and Guofa Cai. "Design of a New Non-Coherent Cross-QAM-Based M-ary DCSK Communication System." Electronics 11, no. 19 (September 29, 2022): 3128. http://dx.doi.org/10.3390/electronics11193128.

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In this paper, a new non-coherent cross-quadrature amplitude modulation (XQAM)-based M-ary differential chaos shift keying (XQAM-MDCSK) system is proposed. In such a system, an autocorrelator is adopted at the receiver to obtain the channel compensation value. This framework can be extended to various amplitude phase shift keying-based MDCSK systems, such as star QAM-based MDCSK (star QAM-MDCSK) and square QAM-based MDCSK (SQAM-MDCSK) systems. Moreover, the bit error rate (BER) expression of the proposed XQAM-MDCSK system is derived over a multipath Rayleigh fading channel. Results show that the proposed XQAM-MDCSK system can achieve better BER performance and a lower peak-to-average power ratio (PAPR) compared to the star QAM-MDCSK system. Furthermore, we also show that the performance of the proposed system can be close to that of a system with perfect channel state information (CSI).

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Journal articles on the topic 'QAM'

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