Chapter 13
Resource Allocation for the Differentially Modulated Cooperation-Aided Cellular Uplink in Fast Rayleigh Fading Channels
13.1 Introduction1
13.1.1 Chapter Contributions and Outline
It was observed in Chapter 12 that the differentially modulated user-cooperative uplink systems employing either the DAF scheme of Section 12.3.2.1 or the DDF scheme of Section 12.3.2.2 were capable of achieving cooperative diversity gain while circumventing the cost and size constraints of implementing multiple antennas in a pocket device. Additionally, by avoiding the challenging task of estimating all the (Nt × Nr) CIRs of multi-antenna-aided systems, the differentially encoded cooperative system may exhibit a better performance than its coherently detected, but non-cooperative, counterpart, since the CIRs cannot be perfectly estimated by the terminals. The CIR estimation becomes even more challenging when the MS travels at a relatively high speed, resulting in a rapidly fading environment. On the other hand, although it was shown in Chapter 12 that a full spatial diversity can usually be achieved by the differentially modulated user-cooperative uplink system, the achievable end-to-end BER performance may significantly depend on the specific choice of the cooperative protocol employed and/or on the quality of the relay channel. Therefore, in the scenario of differentially modulated cooperative uplink systems, where multiple cooperating MSs are roaming in the area between a specific MS and ...
