پديد آورنده :
غلامي، محمد
عنوان :
كدهاي با ماتريس بررسي توازن خلوت بر پايه مفهوم شيب
گرايش تحصيلي :
رياضي كاربردي گرايش كد گذاري
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده علوم رياضي
صفحه شمار :
[هشت]، 176، [II]ص: جدول، نمودار
يادداشت :
ص.ع به: فارسي وانگليسي
استاد راهنما :
مرتضي اسماعيلي
استاد مشاور :
محمدعلي خسروي فرد
واژه نامه :
انگليسي به فارسي
توصيفگر ها :
كدLDPC , نظريه گراف , گراف استوانه اي , گراف ساختاري و گراف تنر
تاريخ نمايه سازي :
88/2/21
استاد داور :
فرشاد لاهوتي، معصومه نصيري، غلامرضا اميدي، بهناز عمومي
عنوان فرعي :
،يا، كدهاي خلوت خوش ساختار با كمر بالا
تاريخ ورود اطلاعات :
1396/07/18
كد ايرانداك :
ID231 دكتري
چكيده فارسي :
به فارسي وانگليسي: قابل رويت در نسخه ديجيتال
چكيده انگليسي :
Slope based Low density Parity check Codes Mohammad Gholami m gholami@math iut ac ir March 2009 Doctor of Philosophy Thesis Department of Mathematical Sciences Isfahan University of Technology Isfahan 84156 83111 IranSupervisor Dr Moreteza Esmaeili emorteza@cc iut ac ir Advisor Dr Mohammad Ali Khosravifard khosravi@cc iut ac ir Dept of Mathematical Sciences Isfahan University of Technology Isfahan 84156 83111 Iran Dept of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Abstract A column weight two parity check matrix H is represented by a graph known asstructure graph In this thesis construction and analysis of slope based low densityparity check LDPC codes having a cylinder structure graph is considered In par ticular design of codes with maximum possible girth is addressed Depending onthe row weight of H three types of codes referred to as type I type II and type IIIcodes with maximum girth 16 24 and 12 respectively are distinguished Deterministiclow complexity algorithms constructing such codes are given The convolutional codesassociated with these three types of codes are analyzed and it is shown that the freedistance of a so constructed convolutional code is equal with the minimum distance ofthe corresponding block code Replacing cylinder structure graphs with the cylinder structure graphs having diam eters we obtain two classes of variable high rate slope based column weight two codeswith maximum girths 20 and 16 These ve classes of maximum girth column weight two codes outperform their al gebraic and random like counterparts when applied on an AWGN channel and decodedwith sum product iterative decoding algorithm The de nition of structure graphs is extended to a new concept referred to as block structure graphs representing codes having parity check matrices with arbitrary columnweight and consisting of circulant matrices Using this and the slope concept we designcodes of girth at most 18 Simulation results con rm that from performance perspectivethe constructed codes outperform their LDPC pseudo random counterparts Key WordsLDPC codes Tanner graph girth Convolutional codes Quasi Cyclic codes slope 1
استاد راهنما :
مرتضي اسماعيلي
استاد مشاور :
محمدعلي خسروي فرد
استاد داور :
فرشاد لاهوتي، معصومه نصيري، غلامرضا اميدي، بهناز عمومي
