Download or read book Peak to Average Power Ratio PAPR Reduction in MIMO OFDM System written by Gangat Mohsin Salim and published by . This book was released on 2016-06-07 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Peak to Average Power Ratio Reduction in OFDM Systems written by Anusha Chacko and published by LAP Lambert Academic Publishing. This book was released on 2015-04-17 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Orthogonal Frequency Division Multiplexing (OFDM) is a promising technology in wireless communication. High Peak-to-Average Power Ratio (PAPR) is one of the challenging issues of OFDM systems. High PAPR forces the High Power Amplifier (HPA) to operate in its linear region with wide dynamic range, where the power efficiency is very poor. This book gives an overview of different PAPR reduction techniques. And deals in detail with the efficient use of Selected Mapping (SLM) and Partial Transmit Sequence (PTS)technique to reduce high PAPR in OFDM systems.
Download or read book Peak to Average Power Ratio Reduction for MIMO OFDM Systems written by Isabela Braz and published by . This book was released on 2010 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wireless OFDM and MIMO OFDM Communications written by P. Mukunthan and published by LAP Lambert Academic Publishing. This book was released on 2014-06-14 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present wireless systems aim for two conflicting goals, viz., providing quality of service such as delay, fairness to users, and maximizing the throughput of the system. Several techniques have been developed for increasing bandwidth with high data rate. Among these techniques, Orthogonal Frequency Division Multiplexing (OFDM) is a special form of multicarrier technique where all the subcarriers are orthogonal to each other. OFDM offers higher data rate and high immunity to the multipath fading channel without degrading the Bit Error Rate (BER) performance. It has gained popularity for broadband communication system because of its high spectral efficiency and capacity to combat multipath fading. At the same time, it has some limitations such as Inter-Symbol Interference (ISI), Inter-Carrier Interference (ICI) and high Peak-to-Average Power Ratio (PAPR). This book contain seven chapters and an attempt has been made in this research work to enhance the power amplifier efficiency and reduce the high PAPR of the OFDM and MIMO-OFDM systems through modified PTS approach combined with some PAPR reduction techniques.
Download or read book Fast Peak power Reduction for MIMO OFDM Systems with Diversity written by Theodoros Tsiligkaridis and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A robust peak-power reduction technique called active constellation extension (ACE) reduces the peak-to-average power ratio (PAPR) of single-input single-output (SISO) orthogonal frequency-division modulated (OFDM) signals by extending the outer constellation points in a way that minimizes the PAPR of an OFDM transmit signal, without reducing the bandwidth or increasing bit error rate (BER). Recent work includes extensions of the concept of ACE using a modi ed smart gradient-project algorithm for MIMO-OFDM systems. We extend the e cient ACE smart gradient-project (SGP) method to space-time block coded (STBC), space-frequency block coded (SFBC) and V-BLAST OFDM systems. The proposed peak-power reduction method can be applied to any space-time-frequency (STF) block code, and its performance is bounded by the code structure. Simulations show PAPR reduction gains of 4.19 and 3.57 dB under QPSK for Alamouti STBC and SFBC, respectively. In addition, we extend the e cient ACE-SGP method to rotated constellations for SISO-OFDM systems, an alternative method recently invented for providing diversity. Simulation results show approximately 3.46 dB and 2.08 dB of PAPR reduction for QPSK and 16-QAM original constellations, respectively, for 256 subcarriers. Results also show that 4.29 dB and 3.41 dB of PAR reduction are obtained for QPSK and 16-QAM original constellations, respectively, for 1024 subcarriers. Furthermore, we show how the PAPR reduction method known as tone injection can be a very practical transmission scheme for coded-OFDM systems, with a slight compromise of the BER performance. This is accomplished by developing e cient, near-optimal, convolutional and LDPC decoders for the extended non-bijective constellations introduced by tone injection. Simulation results for convolutional and LDPC coded-OFDM systems show BER performance comparable to conventional coded OFDM with greatly reduced PAPR. Furthermore, results show that the PAPR performance obtained is very close to the 64-QAM single-carrier peak-power performance. So, the peak-power problem is solved for large constellations.
Download or read book Peak to Average Power Ratio Reduction in STBC MIMO OFDM written by Kishor Gannamaneni and published by . This book was released on 2014 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: Orthogonal frequency division multiplexing (OFDM) is an advanced 3G/4G scheme which achieves high data rate and combats multipath fading. However, OFDM systems suffer from nonlinear peak to average power ratio (PAPR) and carrier frequency offsets (CFO). These two factors lead to degraded performance and thereby reducing the system efficiency. OFDM with multiple antennas both at transmitter and receiver and space-time block coding is used to increase the channel capacity and receiver diversity. Space-time block coding is used to increase data rate and for reliable communications. With space-time block coding we can take advantage of both space and time. It is also possible to implement spatial multiplexing using space-time block coding. However, MIMO-OFDM also suffers from high PAPR value. Many methods have been proposed to reduce the PAPR problem in OFDM. Distortion techniques, coding techniques and scrambling techniques are some of those methods. These methods can be extended to MIMO-OFDM. Distortion techniques can reduce the PAPR, but in turn it increases bit error rate. Coding techniques have limitations with number of subcarriers. Scrambling techniques can reduce the PAPR effectively. In this paper we used SLM and PTS methods to reduce the PAPR problem in MIMO-OFDM. The bit error rate performance for each method is plotted and compared with each other. BER performance of MIMO is compared with SIMO and MISO.
Download or read book An Investigation of Peak To Average Power Reduction written by Yi Wang and published by LAP Lambert Academic Publishing. This book was released on 2010-06 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) technology is one of the most attractive candidates for fourth generation(4G)mobile radio communication. It effectively combats the multipath fading channel and improves the bandwidth efficiency. At the same time, it also increases system capacity so as to provide a reliable transmission. However, the main drawback of MIMO-OFDM system is high peak-to-average power ratio (PAPR) for large number of sub-carriers, which result in many restrictions for practical applications. Coding, phase rotation and clipping are among many PAPR reduction schemes that have been proposed to overcome this problem. In this thesis, we will mainly investigate the PAPR reduction performance with two different PAPR reduction methods: partial transmit sequence (PTS) and selective mapping(SLM). These two methods are sub- entities of phase rotation scheme. In addition, several corresponding modified algorithms are studied with respect to balanced performance and applicability.
Download or read book PAPR Reduction Techniques Analysis and Applications written by Dr. RAJKUMAR L. BIRADAR and published by Archers & Elevators Publishing House. This book was released on with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reducing the Peak to Average Power Ratio of MIMO OFDM Using Particle Swarm Optimization Based PTS written by Asim M. Mazin and published by . This book was released on 2013 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis we proposed PSO based PTS to accomplish the lowest Peak-to-Average Power Ratio of MIMO-OFDM system. We applied the PSO based PTS on each antenna of the system in order to find the optimal phase factors which is a straightforward method to get the minimum PAPR in such a system. The performance of PSO based PTS algorithm in MIMO-OFDM with a wide range of phase factor tends to give a high performance according to the simulation results. In addition, there is no need to increase the number of particles of the PSO algorithm to enhance the performance of the system, which keeps the complexity of finding the minimum PAPR reasonable.
Download or read book PAPR Reduction Channel Estimation Techniques For MIMO OFDMA Systems written by D. M. Motiur Rahaman and published by . This book was released on 2014-08-09 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Peak to Average Power Ratio Reduction for Coded MIMO OFDM written by Harish Reddy and published by . This book was released on 2003 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selective Mapping technique for PAPR reduction in LTE OFDM Systems written by Neelam Dewangan and published by GRIN Verlag. This book was released on 2012-11-22 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Master's Thesis from the year 2012 in the subject Engineering - Communication Technology, grade: none, , course: M.Tech, language: English, abstract: As a promising technique, OFDM has been widely used in emerging broadband communication systems, such as digital audio broadcasting (DAB), high-definition television (HDTV), wireless local area network (IEEE 802.11a and HIPERLAN/2). However, as the OFDM signals are the sum of signals with random amplitude and phase, they are likely to have large PAPR that requires a linear high-power- amplifier (HPA) with an extremely high dynamic range, which is expensive and inefficient. Furthermore, any amplifier nonlinearity causes intermodulation products resulting in unwanted out-of-band power. A number of approaches have been proposed to deal with the PAPR problem, including clipping, clipping-and-filtering (CF), coding, companding transform, active constellation extension (ACE), selected mapping (SLM), partial transmit sequence (PTS), and so on. This thesis proposes an improvement in Selected Mapping technique and Simulation results are compared to existing techniques namely Exponential Companding Transform, Repeated Clipping and Filtering and Adaptive Active Constellation Extension. The improvements which are proposed in classical Selective Mapping technique satisfies the PAPR Reduction criteria with reducing the computational complexity. Also this new scheme has an important advantage of avoiding the extra bits along with the transmitted OFDM signal .This scheme can also be applied to the multiple transmitting antenna cases.
Download or read book Peak to average Power Ratio and Intercarrier Interference Reduction Techniques in MIMO OFDM System written by Sharifah Kamilah Syed Yusof and published by . This book was released on 2006 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Peak to Average Power Ratio Reduction and Error Control in MIMO OFDM HARQ System written by Francisco Alberto Sandoval Noreña and published by . This book was released on 2019 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Enhanced Peak to Average Power Ratio PAPR Algorithm in Long Term Evolution LTE Standard written by Mohanad Janat and published by . This book was released on 2014 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Long Term Evolution (LTE), is an OFDM based system considered the 4G standard that supports high mobility up to 350km/h and high bandwidths. However, LTE suffers from high peak to average power ratio (PAPR) which critically affects the system performance by increasing the bit error rate and decreasing the spectral efficiency. Many solutions have been introduced to the LTE standard to overcome this issue. A hardware solution has been suggested utilizes high power amplifiers with very wide linearity area covering the high peak area of the OFDM symbol, but, the solution is expensive rendering it not affordable by end users. Thus, PAPR reduction algorithms come into place to resolve the issue by manipulating the OFDM symbols blocks produced by MIMO-OFDM systems. The result is an increase in the efficiency of the whole system by reducing PAPR. However, a lot of these algorithms suffer increasing computational complexity to achieve high PAPR reduction performance which affects the overall circuitry complexity. A modified algorithm has been proposed in this research that aims to achieve high PAPR reduction performance while keeping the computational complexity level as low as possible. A modified Cross Antenna Rotation and Inversion (CARI) is introduced in this work, where the normal CARI operations are applied to the first two blocks in the space domain which maintains the circuitry complexity lower than the original CARI, followed by a rotation in the space and frequency domains, hence, utilizing the degree of freedom inherent in both OFDM-MIMO space and frequency domains. The proposed PAPR reduction scheme has been evaluated using Matlab simulator. For simulation approach, the performance metric considered is the Complementary Cumulative Distribution Function CCDF averaged our 105 OFDM symbols. The results have shown that the proposed scheme has better performance by gain of 0.18dB than original CARI at CCDF=10-3 and the sub-blocks M=8. The bench marking against Individual SLM the proposed scheme has shown better performance by gain of 0.5dB than Individual SLM at CCDF=10-3 and the sub-blocks M=8, and finally with concurrent SLM the proposed scheme has better performance by gain of 0.8dB Individual SLM at CCDF=10-3 and the sub-blocks M=8.
Download or read book Peak to average Power Ratio PAPR Reduction Using OFDM Null Subcarriers written by Bo Wang and published by . This book was released on 2011 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Machine Learning and Cognitive Computing for Mobile Communications and Wireless Networks written by Krishna Kant Singh and published by John Wiley & Sons. This book was released on 2020-07-08 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Communication and network technology has witnessed recent rapid development and numerous information services and applications have been developed globally. These technologies have high impact on society and the way people are leading their lives. The advancement in technology has undoubtedly improved the quality of service and user experience yet a lot needs to be still done. Some areas that still need improvement include seamless wide-area coverage, high-capacity hot-spots, low-power massive-connections, low-latency and high-reliability and so on. Thus, it is highly desirable to develop smart technologies for communication to improve the overall services and management of wireless communication. Machine learning and cognitive computing have converged to give some groundbreaking solutions for smart machines. With these two technologies coming together, the machines can acquire the ability to reason similar to the human brain. The research area of machine learning and cognitive computing cover many fields like psychology, biology, signal processing, physics, information theory, mathematics, and statistics that can be used effectively for topology management. Therefore, the utilization of machine learning techniques like data analytics and cognitive power will lead to better performance of communication and wireless systems.
