Cellular CDMA Capacity with Out-of-Band Multihop Relaying
IEEE Transactions on Mobile Computing
Introduction to Space-Time Wireless Communications
Introduction to Space-Time Wireless Communications
Asymptotic Performance Analysis of Blind Minimum Output Energy Receivers for Large DS-CDMA Systems
IEEE Transactions on Signal Processing
Collaborative beamforming for distributed wireless ad hoc sensor networks
IEEE Transactions on Signal Processing
Multiuser detection for cooperative networks and performance analysis
IEEE Transactions on Signal Processing
Optimizing the ARQ performance in downlink packet data systems with scheduling
IEEE Transactions on Wireless Communications
Opportunistic multipath for bandwidth-efficient cooperative multiple access
IEEE Transactions on Wireless Communications
The performance of multi-user cooperative diversity in an asynchronous CDMA uplink
IEEE Transactions on Wireless Communications - Part 2
IEEE Transactions on Information Theory
The art of signaling: fifty years of coding theory
IEEE Transactions on Information Theory
Linear multiuser receivers: effective interference, effective bandwidth and user capacity
IEEE Transactions on Information Theory
Large system performance of linear multiuser receivers in multipath fading channels
IEEE Transactions on Information Theory
Distributed space-time-coded protocols for exploiting cooperative diversity in wireless networks
IEEE Transactions on Information Theory
Cooperative diversity in wireless networks: Efficient protocols and outage behavior
IEEE Transactions on Information Theory
Outage analysis of coded cooperation
IEEE Transactions on Information Theory
Asymptotic spectral efficiency of multiuser multisignature CDMA in frequency-selective channels
IEEE Transactions on Information Theory
Capacity bounds for Cooperative diversity
IEEE Transactions on Information Theory
Achieving Wireline Random Access Throughput in Wireless Networking Via User Cooperation
IEEE Transactions on Information Theory
A simple transmit diversity technique for wireless communications
IEEE Journal on Selected Areas in Communications
Asymptotic analysis and design of multiuser cooperative DS-CDMA systems
ICC'09 Proceedings of the 2009 IEEE international conference on Communications
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In this paper, the performance of the cooperative multiuser direct-sequence code-division multiple-access (DS-CDMA) system is analyzed in the asymptotic regime where both the spreading codes and the number of users grow unboundedly large with the same ratio. Assuming that each terminal is paired with another user which, in addition to transmitting its own data, estimates and relay the information transmitted from its partner, a simple approximate signal-to-interference-plus-noise ratio (SINR) expression is derived that is independent from the spreading codes and explicitly accounts for the effects of the multiple-access interference (MAI) and the relay noise. The so-obtained SINR expression is then computed based entirely on the available local information and without any knowledge about the interfering users. The results obtained above are then used to optimally design the cooperative system. In particular, it is shown how the amount of cooperation between each collaborating pair can be adjusted to simultaneously achieve a preassigned target SINR for both users. Based on the local information, the globally optimal amount of the relay power is obtained that maximizes the achieved SINR at the access point. It is shown that increasing the relay power does not necessarily result in improving the quality of reception at the access point and, to maximize each user's SINR, its relay power should be carefully adjusted based on the environmental parameters such as the interpartner channel link and the powers of MAI and the relay noise. The connection between the cooperative and the conventional multiuser systems is also studied and simulations are used to demonstrate the validity of the analytical results.