Equal power allocation of IDMA systems: feasibility, optimality, and throughput

Authors:
Mark S. K. Lau;Wuyi Yue;Li Ping
Affiliations:
School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore;Department of Intelligence and Informatics, Konan University, Kobe, Japan;Department of Electronic Engineering, City University of Hong Kong, Hong Kong
Venue:
IEEE Transactions on Wireless Communications
Year:
2009

Citing 8
Cited 0

Mitigating multiple access interference and intersymbol interference in uncoded CDMA systems with chip-level interleaving

IEEE Transactions on Wireless Communications
Interleave division multiple-access

IEEE Transactions on Wireless Communications
Optimal transmitter power control in interleave division multiple access (IDMA) spread spectrum uplink channels

IEEE Transactions on Wireless Communications
Power control and capacity of spread spectrum wireless networks

Automatica (Journal of IFAC)
Iterative multiuser joint decoding: optimal power allocation and low-complexity implementation

IEEE Transactions on Information Theory
Interleave-division multiple access and chip-by-chip iterative multi-user detection

IEEE Communications Magazine
Iterative turbo decoder analysis based on density evolution

IEEE Journal on Selected Areas in Communications
Analysis and optimization of CDMA systems with chip-level interleavers

IEEE Journal on Selected Areas in Communications

Quantified Score

Hi-index	0.01

Visualization

Abstract

Equal power allocation (EPA) has been truly successful when applied in IS-95 CDMA. It is therefore worthwhile to see whether EPA is also applicable in IDMA systems, which can be considered as a special case of the direct-sequence CDMA. However, the applicability of EPA in IDMA systems must be considered in light of two fundamental problems. First, EPA is not efficient in suppressing multi-user interference and hence often results in severe performance degradation (infeasibility). Second, EPA schemes often require higher received power than other schemes that allow unequal received powers (sub-optimality). In this paper, we derive the necessary and sufficient conditions for the feasibility and optimality of IDMA systems having equal received powers. The conditions show how feasibility and optimality are related to system parameters such as number of users, code rate and bit-error rate target. The conditions also suggest an upper limit on the throughput of IDMA systems with equal received powers. The results obtained in this paper may provide a theoretical foundation for designing future EPA schemes for IDMA.