Abstract
An algorithm for designing spreading sequences for an overloaded multicellular synchronous DS-CDMA system on uplink is introduced. The criterion used to measure the optimality of the design is the total weighted square correlation (TWSC) assuming the channel state information known perfectly at both transmitter and receiver. By using this algorithm it is possible to obtain orthogonal generalized WBE sequences sets for any processing gain. The bandwidth of initial generalized WBE signals of each cell is preserved in the extended signal space associated to multicellular system. Mathematical formalism is illustrated by selected numerical examples.
Highlights
Due to the emerging demand on new multimedia applications, generation wireless systems are expected to support higher data rates
The recent literature on designing codes for uplink overloaded CDMA systems can be divided into two general categories: those that assume random signature sequences and those that target the optimization of given criterion
Real sequences, which meet the lower bound of total squared correlation (TSC) and total weighted square correlation (TWSC), are called Welch bound equality (WBE) and generalized WBE sequences, respectively
Summary
Due to the emerging demand on new multimedia applications, generation wireless systems are expected to support higher data rates This goal is challenging for the systems that are power, bandwidth, and complexity limited. The recent literature on designing codes for uplink overloaded CDMA systems can be divided into two general categories: those that assume random signature sequences and those that target the optimization of given criterion. By solving an inverse eigenvalue problem of the structured block matrices, an algorithm that overcomes the limitations of previous algorithms is derived. It is based on majorization theory and it allows obtaining generalized WBE sequences for any signal space dimensionality of each cell under TWSC criterion.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: EURASIP Journal on Wireless Communications and Networking
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
