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H Ybrid Qam - Fsk Hqfm Ofdm T Ransceiver With L Ow Papr

Thesis Info

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Author

Latif, Asma

Program

PhD

Institute

Ghulam Ishaq Khan Institute of Engineering Sciences and Technology

City

Swabi

Province

KPK

Country

Pakistan

Thesis Completing Year

2009

Thesis Completion Status

Completed

Subject

Applied Sciences

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/2073/1/22S.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726353280

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Orthogonal Frequency Division Multiplexing (OFDM) is an attractive multicarrier technique for mitigating the effects of multipath delay spread of radio channel, and hence accepted for several wireless standards as well as number of mobile multimedia applications. Alongside its advantages such as robustness against multipath fading, spectral efficiency and simple receiver design, OFDM has two major limitations. One of these is its sensitivity to carrier frequency offsets (CFO) caused by frequency differences between the local oscillators in the transmitter and the receiver and the other is high peak to average power ratio (PAPR). This high PAPR is due to the summation of sinc-pulses and non-constant envelope. Therefore, RF power amplifiers (PA) have to be operated in a very large linear region. Otherwise, the signal peaks get distorted, leading to intermodulation distortion (IMD) among the subcarriers and out-of-band radiation. A simple way to avoid is to use PA of large dynamic range but this makes the transmitter 1 Dr. Nasir D. Gohar is currently Professor/HoD, Communication Systems Engineering Department at NUST School of Electrical Engineering and Computer Science, Islamabad. ivcostly. Thus, it is highly desirable to reduce the PAPR. In order to reduce the PAPR, several techniques have been proposed such as clipping, coding, peak windowing, Tone Reservation (TR), Tone Injection (TI), Selected Mapping (SLM) and Partial Transmit Sequence (PTS). After studying these schemes, it was found that most of these methods are unable to achieve simultaneously a large reduction in PAPR with low complexity, low coding overhead and without performance degradation and transmitter/ receiver symbol handshake. In this study, an OFDM transceiver is proposed which makes use of hybrid modulation scheme instead of conventional modulator like QAM or PSK. In addition to improved BER performance both in AWGN and frequency selective fading channel, it exhibits low PAPR. The modified OFDM transceiver makes use of multilevel QAM constellations, where the level of QAM is decided by specific number of bits chosen arbitrarily from a group of bits to be encoded in the QAM symbol. The simulated results show that PAPR is considerably reduced, though at the cost of a slight increase in detection complexity. Like PTS or SLM, it works with arbitrary number of subcarriers but needs no side information to be transmitted. It is also shown that PAPR reduction capability of the proposed system is comparable to PTS. However, to further reduce the PAPR, one has to alter this hybrid MQAM/LFSK (HQFM) signal sets like in PTS, but there is no need of transmitting any additional side information. At the receiver, these deformations can be removed in one or two iterations, thus, original data retrieved but with a little increase in the receiver complexity.
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حضرت پیر جلیل احمد اخون

حضرت پیر جلیل اخون
بخشش لئی ہے نیک شگون
پیر نیاز محمد نے جد ایتھے لائیاں تلیاں
دین نبیؐ دی شمع نال چا روشن کیتیاں گلیاں
ایڈی دین دی خدمت کیتی داد دتی سی ولیاں
دین دی خدمت کارن ہر کوئی آپ دا سی ممنون
ایڈے زاہد عالم کامل وچ زمانے فردا
قدراں دے نال جانے ہر کوئی گلہ نہ کوئی کردا
حافظ، قاری، عالم، کامل ہر کوئی پانی بھردا
باقی سب ستارے نیں تے آپ انہاندے ’’مون‘‘
بابا جی دے بیٹے سارے پیار بھرے نے بھائی
پیر جلیل نے ودھ انہاں توں بہتی شہرت پائی
ایڈے زاہد، کامل، اکمل، فقر دی جوت جگائی
آپ دی جے کر محفل بہئے ملدا بڑا سکون

شیخ کبیر اختر سائیں توں فیض روحانی پائے
ایڈا ادب تے خدمت کیتی بن مخدوم سی آئے
خالی کدی نہ پرتے جیہڑے خدمت دے وچ آئے
فائدہ ہر نوں ملدا جیویں فائدہ دیوے زمین وہون
ایڈا وڈا دین دا مرکز بچے پڑھن ہزاراں
فقہ ، حدیث ، قرآن، فقر دیاں لگیاں موج بہاراں
رم جھم رحمتاں برسن ایتھے ہووے شفا بیماراں
کامل پیر دے چرناں وچ ناں وڑدا شیطان ملعون
ظاہر باطن فیض انہاندا ہر ہر جائیں ملدا
جھنڈا لایا بدر عالم جو اجے وی ایتھے ہلدا
آپ دی جامع دا پڑھیا تے علم دریا تھیں ٹھلدا
لکھ ہنیریاں گھلن قائم رہے گا دین دا ایہہ ستون
دستار مبارک جبہ عاصا بوہت حضرت نوں سجدا
تکدا جیہڑا ہک واری اوہ ویکھ ویکھ ناں رجدا
شہرت ملدی نال نصیباں ، کرم ہے سوہنے رب دا
مفتی خلیق ہے آپ نوں جیویں موسیٰ نوں ہارون

تفسیر‘‘محاسن التاویل’’ میں جلال الدین قاسمی کے منہج کا تحقیقی مطالعہ

Brought up in the context of a very critical time of Islamic history, Imām Muḥammad Jalāl’uddīn Qāsimī (1866-1914) played a vital role to reform and purify the ongoing mindset of the Muslims in Syria in his time. He was a man believed in an independent thinking in the light of the Qur’ān and Sunnah. He taught the people to get rid of the backwardness and blind imitation (Taqlīd). For this purpose of his, he presented the works of the previous leading Islamic Scholars as they were. He was expert in various fields of knowledge like Qur’ān, Ḥadīth and their Sciences, Jurisprudence, Dialectic, etc. One of his masterpieces is his exegesis known as “Maḥāsin al-Tāwīl”. It is a great exegetical work; as most of the exegetical aspects are entertained in it. It has nine or seventeen volumes according to its two different editions, including a whole volume of preamble containing eleven Rules of Quranic Sciences. Although the critics object to his copying the long paragraphs of the prominent Islamic Scholars without commenting or editing and on his long discussions that deviate the reader from the actual purpose of the Holy Qur’ān, but to present the material in this way for the purpose of reformations of Muslims and to bring them back to the way of Salaf through their words, in that crucial time, justifies the significance of the work. In this article, the author probes to present the mythology adopted by Imām Qāsimī in his exegesis and its scholarly merits.

Resistance Against NEO-Colonialism in a Small Place by Jamaica Kincaid and Devil on the Cross by Ngugi Wa Thiong'O

A Study of Saraiki Speaker' Attitudes towards English Lexical Borrowing in Saraiki Language Attitude towards a language is considered to be a premise which particularly highlights linguistic behavior that may be favorable or unfavorable. Pakistan being a multilingual country has a diglossic situation where two or three languages are used by the same speech community. Nevertheless, these vernaculars vary in prestige, rank, and effectiveness which authorize them either as greatly prestigious or poorly valued languages. In Pakistan, English is taken as a highly esteemed while Saraiki as a less privileged language. This specific study aimed to explore Saraiki speakers’ attitudes towards English lexical borrowing in Saraiki language. The data of this specific research was gathered through the administration of close ended questionnaire survey upon a total of 150 randomly chosen educated sample of both gender and of different age groups. By using SPSS version 22, the collected data was computed, evaluated as well as tabulated. This study discovered a difference in the speakers’ attitudes based on the demographic profile such as age and gender. The findings and outcomes recommend that the study respondents conveyed highly positive attitude towards English lexical borrowing in Saraiki language. This could be documented to the fact that participants were highly motivated towards English language, some recommendations are finally proposed.