VTechWorks is currently accessible only on the VT network (campus, VPN). Elements deposit is now enabled. We are working to restore full access as soon as possible.
 

Channel modeling and interference rejection for CDMA automatic vehicle monitoring systems

Simple item page
dc.contributor.authorZheng, Raymond Sihaoen
dc.contributor.departmentElectrical Engineeringen
dc.date.accessioned2014-03-14T21:40:19Zen
dc.date.adate2009-07-11en
dc.date.available2014-03-14T21:40:19Zen
dc.date.issued1994en
dc.date.rdate2009-07-11en
dc.date.sdate2009-07-11en
dc.description.abstractIt is desirable to develop a universal digital receiver which is capable of operating with many different wireless communication systems. Time Dependent Adaptive Filter (TDAF) Processing represents an effective approach for CDMA interference rejection. This technique is especially appropriate at the mobile receiver where there is little prior knowledge of the spreading codes of the other users. This thesis presents enhanced forms of the Time Dependent Adaptive Filter (TDAF), which is an optimal periodically time-varying adaptive filter. It is able to fully exploit the cyclostationarity and spectral correlation in certain DS-SS signals. It is shown how multiple AVM service providers can exist in adjacent channels within the ISM band. It is demonstrated that using the realistic channel models the TDAF can provide substantial improvement in interference rejection over the conventional correlation receiver. Computationally efficient TDAF structures have been also proposed to handle the case of different code repeat intervals for different systems. Results of CDMA overlay system simulation have shown that TDAF processing can achieve tremendous gain in narrowband interference rejection compared to notch/matched filter processing. An input signal which has 45 dB narrowband interference-to-signal power ratio (J/S), the SIR of the TDAF processed output signal can be 20 dB, a 65 dB improvement. The use of TDAF processing and a spectral shaping filter can minimize the impact of adjacent channel interference. Even in an environment which has a 30 dB adjacent channel J/S, the SIR at output is demonstrate to be a 50 dB improvement. System performance shows little degradation by adjacent channel and narrowband interference.en
dc.description.degreeMaster of Scienceen
dc.format.extentviii, 102 leavesen
dc.format.mediumBTDen
dc.format.mimetypeapplication/pdfen
dc.identifier.otheretd-07112009-040511en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-07112009-040511/en
dc.identifier.urihttp://hdl.handle.net/10919/43690en
dc.language.isoenen
dc.publisherVirginia Techen
dc.relation.haspartLD5655.V855_1994.Z556.pdfen
dc.relation.isformatofOCLC# 32457422en
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subject.lccLD5655.V855 1994.Z556en
dc.subject.lcshCode division multiple accessen
dc.subject.lcshMobile communication systemsen
dc.titleChannel modeling and interference rejection for CDMA automatic vehicle monitoring 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_1994.Z556.pdf
Size:
4.1 MB
Format:
Adobe Portable Document Format
Description:
Download

Collections

Masters Theses