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Home > Peak to Average Power Ratio Reduction in Orthogonal Frequency Division Multiplexing Systems

Peak to Average Power Ratio Reduction in Orthogonal Frequency Division Multiplexing Systems

Thesis Info

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External Link

Author

Khalid, Seema

Program

PhD

Institute

University of Engineering and Technology

City

Taxila

Province

Punjab

Country

Pakistan

Thesis Completing Year

2009

Thesis Completion Status

Completed

Subject

Applied Sciences

Language

English

Link

http://prr.hec.gov.pk/jspui/handle/123456789/1666

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726849079

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One of the major drawbacks of OFDM has been the high peak-to-average power ratio (PAPR) that is characteristic of signals with multiple sub-carriers. The high PAPR requires additional back off to achieve linear amplification at the transmitter end which results in inefficient power consumption. This inefficient power consumption is the major impediment in implementing OFDM in portable device. Previous efforts to address this problem have been principally directed at two areas, the reduction of signal PAPR and various methods of achieving linear and efficient power amplification (PA). However, all approaches suffer due to various deficiencies such as complexity, computational time, memory requirements, data rate loss and high distortion. Therefore, this thesis aimed at finding the solution of power control problem by reducing the PAPR of the signal. Two novel techniques are proposed in this thesis. One of the techniques is based on distortion class named as Zero Forcing Peaks (ZFP) and the other is based on Selected Mapping (SLM) technique from probabilistic class. In this thesis a new concept of using Learning Vector Quantization (LVQ) along with SLM has been introduced which is named as LVQ-SLM and can be considered as a major contribution of this thesis. Further two different architectures are proposed for LVQ-SLM and their practicability is investigated by synthesizing these architectures on Field Programmable Gate Arrays FPGA. Result obtained using second technique is quite encouraging. An efficient implementation of SLM is achieved by using LVQ network as it reduces PAPR with minimal computational complexity. The only constrain which has been noted when the number of sub carriers and modulation order increase, the on-chip memory to store prototype vectors and computational requirements also increase. High capacity low power Content addressable memory (CAMs) based hardware can be used to solve this constrain which has also been proposed in this thesis.
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قاضی سلیمان منصور پوری

قاضی سلیمان صاحب منصور پوری
وہ مشرقی فاضل جس کی موت پر آج ہم کو ماتم کرنا ہے وہ قاضی محمد سلمان منصور پوری سابق جج پٹیالہ اور سیرت کی مشہور کتاب ’’رحمۃ للعالمین‘‘ کے مصنف ہیں، وہ علم و عمل، زہد و کمال اور فضل و ورع دونوں کے جامع تھے، روشن دل اور دماغ تھے، ان کے جدید و قدیم دونوں خیالات حداعتدال پر تھے، عربی زبان اور علوم دین کے مبصر عالم تھے، توراۃ و انجیل پر فاضلانہ و ناقدانہ نگاہ رکھتے تھے، غیرمسلموں سے مناظرہ کے شائق تھے، مگر ان کے مناظرہ کا طرز سنجیدگی، متانت اور عالمانہ وقار کے ساتھ تھا، مسلکاً اہل حدیث تھے، مگر اماموں اور مجتہدوں کی دل سے عزت اور ان کی محنتوں اور جانفشانیوں کی پوری قدر کرتے تھے۔
وہ ندوۃ العلماء کے دیرینہ رکن تھے اور اسی وساطت سے ان سے تعارف حاصل ہوا، اور تعارف نے باہم انس و مودّت کی صورت پیدا کی، جب مل جاتے دیر تک ہم ذوقی کا لطف قائم رہتا، سیرۃ، جدید مناظرات و کلام اور محاسن اسلام کے مختلف پہلوؤں پر گفتگو رہتی، اور اس لطف میں تھوڑی دیر کے لئے ہر چیز فراموش ہوجاتی، چند سال ہوئے کہ دارالمصنفین بھی ان کے فیض قدوم سے منور ہوا تھا، بلند قامت، خوش رو، خوش لباس، وجیہ، گھنی داڑھی، سپید صافہ باندھا کرتے تھے۔
ان کی مستقل تصنیفات میں رحمۃ للعالمین، الجمال والکمال (تفسیر سورۂ یوسف) اور سفرنامۂ حجاز، یادگار ہیں، ان کے علاوہ چھوٹے بڑے بیسوں رسائل ان کے قلم سے نکلے، مگر سب سے زیادہ ’’رحمۃ للعالمین‘‘ نے قبولیت حاصل کی، اسلامی مدرسوں میں داخل ہوئی، کورسوں میں شامل ہوئی، لوگوں نے ذوق و شوق سے پڑھا، خدا رحمۃ للعالمین کے مصنف کو اپنی رحمت عالم سے نوازے۔
سات آٹھ برس ہوئے کہ وہ ایک دفعہ...

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