Random matrix theory and wireless communications
Communications and Information Theory
Particle swarm optimization for multiuser asynchronous CDMA detector in multipath fading channel
WSEAS Transactions on Computers
Optimum pilot-to-data power ratio for partial RAKE receiver in nakagami-m fading channels
IEEE Transactions on Wireless Communications
Random DS/CDMA for the amplify and forward relay channel
IEEE Transactions on Wireless Communications
IEEE Transactions on Information Theory
Employing LSF at transmitter eases MMSE adaptation at receiver in asynchronous CDMA systems
EURASIP Journal on Wireless Communications and Networking
Asymptotic analysis of outage region in CDMA MIMO systems
IEEE Transactions on Information Theory
Asynchronous CDMA systems with random spreading-part I: fundamental limits
IEEE Transactions on Information Theory
Effect of chip-level asynchronism on a CDMA-based overlay system for optical network management
IEEE Journal on Selected Areas in Communications - Special issue on next-generation broadband optical access network technologies
Power control and capacity of spread spectrum wireless networks
Automatica (Journal of IFAC)
Admission control in UMTS in the presence of shared channels
Computer Communications
| Hi-index | 755.02 |
The performance of linear multiuser receivers in terms of the signal-to-interference ratio (SIR) achieved by the users has been analyzed in a synchronous CDMA system under random spreading sequences. In this paper, we extend these results to a symbol-asynchronous but chip-synchronous system and characterize the SIR for linear receivers-the matched-filter receiver the minimum mean-square error (MMSE) receiver and the decorrelator. For each of the receivers, we characterize the limiting SIR achieved when the processing gain is large and also derive lower bounds on the SIR using the notion of effective interference. Applying the results to a power controlled system, we derive effective bandwidths of the users for these linear receivers and characterize the user capacity region: a set of users is supportable by a system if the sum of the effective bandwidths is less than the processing gain of the system. We show that while the effective bandwidth of the decorrelator and the MMSE receiver is higher in an asynchronous system than that in a synchronous system, it progressively decreases with the increase in the length of the observation window and is asymptotic to that of the synchronous system, when the observation window extends infinitely on both sides of the symbol of interest. Moreover, the performance gap between the MMSE receiver and the decorrelator is significantly wider in the asynchronous setting as compared to the synchronous case