رسالة جامعية
Diversity performance of DS-CDMA systems in multipath fading channels
| العنوان: | Diversity performance of DS-CDMA systems in multipath fading channels |
|---|---|
| المساهمون: | Efthymoglou, George P., Florida Atlantic University (Degree grantor), Helmken, Henry (Thesis advisor), College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science |
| بيانات النشر: | Florida Atlantic University |
| المجموعة: | FAU Digital Collections (Florida Atlantic University Digital Library) |
| مصطلحات موضوعية: | Mobile communication systems, Wireless communication systems, Radio wave propagation |
| الوصف: | In this dissertation, new semi-analytical expressions for the diversity bit error rate performance of asynchronous direct sequence-code division multiple access (DS-CDMA) systems in multipath fading channels are derived. Also, the PN acquisition time of a DS system with offset frequency periods greater than the code period in a AWGN channel is measured via laboratory experiments. In Part I we consider DS-CDMA systems operating in a cellular environment with multipath reception. Multipath propagation is exploited through the use of RAKE receivers. Coherent, differentially coherent and noncoherent binary demodulation schemes are considered. The multiple access interference is modeled as AWGN, conditioned on the fading statistics of the received signal. The mobile radio channel introduces selective fading, and is modeled as a tapped delay line. The amplitude of each resolvable path is statistically described by the Nakagami distribution, which is a general solution to the random vector problem that causes rapid fading. However, we assume independent but nonidentical fading along the RAKE branches. Therefore our analysis supports unequal mean powers and different amount of fading in the multipath components combined by the receiver. Also, the results can be easily extended to account for diversity from multiple antennas or coding in the generalized Nakagami multipath fading environment. In Part II we consider a land mobile satellite channel. First, a laboratory experiment is setup to evaluate the PN acquisition performance of a digital IF receiver in a AWGN channel with large Doppler offset. The digital conversion receiver uses the inherent aliasing property of sampling to realize the baseband conversion using a single analog-to-digital converter. Thereafter, digital signal processing on the I and Q samples enable for design trade-offs in the acquisition of the PN code with Doppler periods greater than the code period. Two code phase selection criterions, namely the maximum criterion and the threshold crossing ... |
| نوع الوثيقة: | thesis |
| وصف الملف: | 156 p.; application/pdf |
| اللغة: | English |
| الإتاحة: | http://purl.flvc.org/fcla/dt/12516Test https://fau.digital.flvc.org/islandora/object/fau%3A9407/datastream/TN/view/Diversity%20performance%20of%20DS-CDMA%20systems%20in%20multipath%20fading%20channels.jpgTest |
| حقوق: | Copyright © is held by the author, with permission granted to Florida Atlantic University to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder. ; http://rightsstatements.org/vocab/InC/1.0Test/ |
| رقم الانضمام: | edsbas.F61F2759 |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |