In this paper, we propose a simple diversity-four, two-antenna, two-tone, space-frequency code that combines modulation and coding with knowledge of reduced channel state information at the transmitter. This can find effective application in broadband wireless systems employing MIMO-OFDM. We compare the performance of the proposed code with other diversity-four codes that employ varying amounts of feedback. We show that this code provides an efficient trade-off between performance and feedback rate, which is very modest, while retaining implementation simplicity. © 2007 IEEE.