03798nas|a2200481 i 4500 20260818171352.0 030926s2002 th u m rtt 00| a1eng d .b11900350 AIT Thesis no.TC-02-19 Parames Foomooljareon The peak to average power ratio reduction in OFDM systems Bangkok : Asian Institute of Technology, 2002 58 leaves Thesis ; no. TC-02-19 A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology Thesis (M.Eng.) - Asian Institute of Technology, 2002 Orthogonal Frequency Division Multiplexing or OFDM is a form of multi-carrier modulation technique. High spectral efficiency, robustness to channel fading, immunity to impulse interference, uniform average spectral density, capability of handling very strong echoes and less non linear distortion are among the favorite properties of OFDM. Even though there are many advantages of OFDM, it has two main drawbacks: high Peak to Average Power Ratio (PAPR) and frequency offset. In this thesis, the issue of PAPR reduction in OFDM is discussed. The effect of modulation schemes on PAPR is illustrated at the beginning of the thesis. Two new algorithms are proposed to reduce the PAPR. The first algorithm, Lookup Table Approach, is carried out by selecting the input sequences properly using a lookup table. The second algorithm, Envelope Scaling Approach, is to scale the input envelope for some subcarriers before they are transformed to the time domain by Inverse Fast Fourier Transform (IFFT). Simulation results show that PAPR can be reduced significantly with both schemes. The BER performance for multipath fading channel of the proposed schemes is insignificantly different when comparing to adaptive Partial Transmitted Sequence (PTS). The costs of the proposed schemes are information rate in the Lookup Table approach and the complexity in the Envelope Scaling Approach respectively. Coding theory Modulation theory Fernando, W.A.C., Chairperson Ahmed, Kazi Mohiuddin, Examination Committee Erke, Tapio J., Examination Committee Royal Thai government Fellowship, Scholarship donor Advance Info Service Plc., Scholarship donor Asian Institute of Technology. Thesis ; no. TC-02-19 Full-Text http://203.159.5.9/ait-thesis/detail.php?q=B07581 .b11900350 mnait u 240703 0 030926 m a u 4 mnait mnait mnarc mnarc mnarc 20 40 Barcode : 30050120809958 CREATED : 2002-04-29 RECORD # : i12356815 LPATRON : 1024601 LCHKIN : 2013-09-23 # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 4 TOT RENEW : 4 Barcode : 30050120809966 CREATED : 2002-04-29 RECORD # : i12356827 LPATRON : 1019544 LCHKIN : 2009-09-17 # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 6 TOT RENEW : 8 Barcode : 30050160044912 CREATED : 2016-03-03 RECORD # : i12889106 LPATRON : 0 LCHKIN : - # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 0 TOT RENEW : 0 Barcode : 30050211033419 CREATED : 2021-04-30 RECORD # : i13341455 LPATRON : 0 LCHKIN : - # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 0 TOT RENEW : 0 Barcode : 30050211032338 CREATED : 2021-01-11 RECORD # : i1335338x LPATRON : 0 LCHKIN : - # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 0 TOT RENEW : 0 86059 86059 0 0 0 0 MAIN MAIN mnait 2026-08-18 50.00 0 AIT Thesis no.TC-02-19 30050120809958 2026-08-18 17:13:52 1 2026-08-18 20 0 0 0 0 MAIN MAIN mnait 2026-08-18 50.00 0 AIT Thesis no.TC-02-19 30050120809966 2026-08-18 17:13:52 2 2026-08-18 20 0 0 0 0 MAIN MAIN mnarc 2026-08-18 0 AIT Thesis no.TC-02-19 30050160044912 2026-08-18 17:13:52 2026-08-18 40 0 0 0 0 MAIN MAIN mnarc 2026-08-18 50.00 0 AIT Thesis no.TC-02-19 30050211033419 2026-08-18 17:13:52 3 2026-08-18 20 0 0 0 0 MAIN MAIN mnarc 2026-08-18 50.00 0 AIT Thesis no.TC-02-19 30050211032338 2026-08-18 17:13:52 4 2026-08-18 20