Optimum linear single user detection in direct-sequence spread-spectrum multiple access systems

Simple item page
dc.contributor.authorAue, Volkeren
dc.contributor.committeechairReed, Jeffrey H.en
dc.contributor.committeememberWoerner, Brian D.en
dc.contributor.committeememberVanLandingham, Hugh F.en
dc.contributor.departmentElectrical Engineeringen
dc.date.accessioned2014-03-14T21:39:52Zen
dc.date.adate2009-07-10en
dc.date.available2014-03-14T21:39:52Zen
dc.date.issued1995-09-10en
dc.date.rdate2009-07-10en
dc.date.sdate2009-07-10en
dc.description.abstractAfter Qualcomm's proposal of the IS-95 standard, <i>code-division multiple access</i> (CDMA) gained popularity as an alternative multiple-access scheme in cellular and <i>personal communication systems</i> (PCS). Besides the advantage of allowing asynchronous operation of the users, CDMA <i>direct-sequence spread spectrum</i> (DS-SS) offers resistance to frequency selective fading and graceful degradation of the performance as the number of users increases. Orthogonality of the signals in time-division multiple access and frequency-division multiple access is inherent from the nature of the multiple access scheme. In a CDMA system, orthogonality of the signals is not guaranteed in general. Consequently, the performance of conventional correlation receivers suffers. Sub-optimum receivers which use knowledge of the interfering signals have been investigated by other researchers. These receivers attempt to cancel the multi-user interference by despreading the interfering users. Hence, these receivers require knowledge about all the spreading codes, amplitude levels, and signal timing, and are, in general, computationally intensive. In this thesis, a technique is presented for which a high degree of interference rejection can be obtained without the necessity of despreading each user. It is shown that exploiting spectral correlation can help mitigate the effects of the multiple-access interference. If <i>code-on-pulse</i> DS-SS modulation is used, a cyclic form of the Wiener filter provides substantial improvements in performance in terms of bit error rate and user capacity. Furthermore, it is shown, that a special error-criterion should be used to adapt the weights of the filter. The computational complexity of the receiver is equivalent to that of conventional equalizers.en
dc.description.degreeMaster of Scienceen
dc.format.extentx, 68 leavesen
dc.format.mediumBTDen
dc.format.mimetypeapplication/pdfen
dc.identifier.otheretd-07102009-040247en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-07102009-040247/en
dc.identifier.urihttp://hdl.handle.net/10919/43609en
dc.language.isoenen
dc.publisherVirginia Techen
dc.relation.haspartLD5655.V855_1995.A94.pdfen
dc.relation.isformatofOCLC# 35920307en
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectcode-division multiple accessen
dc.subjectcode-on-pulse DS-SS modulationen
dc.subjectCDMAen
dc.subject.lccLD5655.V855 1995.A94en
dc.titleOptimum linear single user detection in direct-sequence spread-spectrum multiple access systemsen
dc.typeThesisen
dc.type.dcmitypeTexten
thesis.degree.disciplineElectrical Engineeringen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
LD5655.V855_1995.A94.pdf
Size:
2.21 MB
Format:
Adobe Portable Document Format
Download

Collections

Masters Theses