A Multi-Cell Space-Time-Coded Transmission Scheme for Single Frequency Networks

Single Frequency Networks (SFN) in combination with a multi-carrier transmission scheme such as OFDM are often proposed as a means to provide continuous coverage of broadcast applications over a large area. While this combination does succeed in providing continuous coverage, it has certain limitations. Specifically, at points where signals from multiple base-stations are received, the overall signal-to-noise ratio can be poor because of relative phase differences. In this paper, we show how, through the use of orthogonal space-time codes, this limitation of SFN's can be overcome to improve their overall performance. This scheme could be viewed as an "open-loop" implementation of multi-cell cooperative transmission.