HSPA+ Evolution to Release 12: Performance and Optimization

3 Multicarrier and Multiantenna MIMO

Antti Toskala, Jeroen Wigard, Matthias Hesse, Ryszard Dokuczal, and Maciej Januszewski

3.1 Introduction

This chapter presents HSPA multicarrier and multiantenna Multiple Input Multiple Output (MIMO) capabilities introduced in Releases 7 onwards all the way to the ongoing Release 12 work on uplink enhancements involving uplink multicarrier operation. Release 99 contained support for base station transmit diversity (both closed and open loop, as covered in [1]), but Release 5 HSDPA and 6 HSUPA were basically designed around a single antenna, single frequency band, and single-carrier operation. This chapter first covers the multicarrier operation introduced with dual-carrier downlink and then extends to more carriers in downlink and also to the dual-carrier uplink operation. This chapter then continues with the multiband capabilities and is concluded with MIMO operation introduced originally in Release 7 and finalized with Release 11 uplink MIMO.

3.2 Dual-Cell Downlink and Uplink

Following the development of the baseband processing capabilities, including handling of larger bandwidths, the work in 3GPP turned towards enabling a single device to use larger bandwidth than the original WCDMA bandwidth of 5 MHz. The definition of, for example, 10 MHz bandwidth with the new chip rate was not a very attractive approach since that would have been a non-backwards compatible solution, not allowing legacy devices to access such a carrier. Thus the ...