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7 articles for “QPSK”
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Research ArticleOpen accessEvery word in the titleSoftware Defined Radio Implementation of a QPSK Modulator/Demodulator in an Extensive Hardware Platform Based on FPGAs Xilinx ZYNQSérgio Bimbi Junior, Vitor Chaves de Oliveira, Gunnar Bedicks JuniorSoftware Defined Radio (SDR) technology enables wireless devices deployment with support to multiple interfaces in modulation formats and it has gained importance due to the current wireless standards proliferation. In order to activate these functionalities it is necessary to apply SDR inside a reconfigurable hardware such as the Field Programmable Gate Array (FPGA). In this study, design procedures developments are … …Journal of Computer Science, Vol. 11, Issue 4 · 2 Jun 2015 · 8,813 accessesView PDFCite
Research ArticleOpen accessIn the keywordsAdaptive Channel Estimation for Multiuser Underwater Communication SystemsS. Aliesawi, C. C. Tsimenidis, B. S. Sharif, M. JohnstonProblem statement: Multiple Access Interference (MAI) signals and poor estimation of the unknown channel parameters in the presence of limited training sequences are two of the major problems that degrade the systems’ performance. Two synchronous multiuser receivers with Rake reception of Interleave Division Multiple Access (IDMA) and Code Division Multiple Access (CDMA) systems, in conjunction with channel estimation, are considered … …American Journal of Engineering and Applied Sciences, Vol. 4, Issue 4 · 20 Feb 2012 · 7,355 accessesView PDFCite
Research ArticleOpen accessIn the keywordsPerformance Analysis of IEEE 802.16d using Forward Error CorrectionVenkatesh Sekar, V. Palanisamy, K. BaskaranProblem statement: Worldwide Interoperability for Microwave Access is the broadband wireless technology for terrestrial broadcast services in Metropolitan Area Networks. This BWA technology is based on Orthogonal Frequency Division Multiplex (OFDM) technology and considers the radio frequency range up to 2-11 GHz and 10-66 GHz. The objective of this research work is the performance analysis of AWGN, SUI-1 and SUI-2 … …Journal of Computer Science, Vol. 7, Issue 3 · 9 Mar 2011 · 7,336 accessesView PDFCite
Research ArticleOpen accessIn the keywordsImplementation of a Novel Concatenated FEC by RS and Irregular Turbo Codes on OFDM SystemsA. Shanmugam, A. R. Abdul Rajak, S. Vishwanath, R. UpendraCode Division Multiple Access (CDMA) performs well in a multi-cellular environment where a single frequency is used in all cells. Code Division Multiple Access (CDMA) has severe problems associated with multipath and Channel news. One possible problem is that the receiver may require a very large dynamic range in order to handle the large signal strength variation among users. Due … …American Journal of Applied Sciences, Vol. 2, Issue 5 · 31 May 2005 · 7,039 accessesView PDFCite
Research ArticleOpen accessIn the keywordsIntelligent Digital Signal Modulation Recognition using Machine LearningMudhafar Haji Mala Abd, Sadegh AminifarInrecent years, modulation type recognition has received a lot of attentionacross the board. There are several methods to detect modulation types, butthere are only a few effective methods to handle signals with a higher level ofnoise. This study introduces an approach to verify the ability of differentmachine learning algorithms to automatically manage noise in detecting digitalmodulations. This research examines two … …Journal of Computer Science, Vol. 18, Issue 10 · 26 Sep 2022 · 6,095 accessesView PDFCite
Research ArticleOpen accessIn the keywordsComparison of Bit Error Rate Performance of Multi Tone Channel Utilising De-OQPSK and De-Off Set 16 QAM with Guard IntervalIbrahim A.Z. QatawnehDigital communications systems use Multi tone Channel (MC) transmission techniques with differentially encoded and differentially coherent demodulation. Today there are two principle MC application, one is for the high speed digital subscriber loop and the other is for the broadcasting of digital audio and video signals. In this study the comparison of multi carriers with OQPSK and Offset 16 QAM … …Journal of Computer Science, Vol. 1, Issue 3 · 30 Sep 2005 · 6,847 accessesView PDFCite
Research ArticleOpen accessIn the abstractReduction of PAPR by Using Clipping and Filtering for Different Modulation SchemesArun Kumar, Manisha GuptaOrthogonal Frequency Division Multiplexing (OFDM) is one of the most advanced technologies for high speed data access in mobile communication. It’s significantly increases the capacity, data-rate etc. but one of its disadvantage is high Peak Average Power Ratio (PAPR) which reduce the performance of transmitter amplifier. In this study, PAPR is reduced by using a clipping and filtering technique for … …American Journal of Applied Sciences, Vol. 13, Issue 2 · 13 Feb 2016 · 8,360 accessesView PDFCite