Symbol timing for multiple antenna OFDM systems

Accurate symbol timing in multiple-input multiple-output (MIMO) OFDM systems allows for guard-intervals (GIs), which are short compared to the channel´s rms delay spread. These short GIs improve the effective throughput of these kind of systems. This paper proposes different timing approaches for MIMO OFDM systems, which apply knowledge about the channel impulse response. The techniques differ in complexity and performance. From a numerical performance study it is concluded that for single-cluster channels and moderate delay spreads the low-complex algorithms can be applied without considerable loss in performance. For high delay spreads and multiple clusters, however, the proposed algorithm, which attempts to maximize the signal-to-inference ratio, is shown to be preferable