Space Time Trellis Coding (STTC) is an extension of Trellis Coded Modulation to multiple transmit antennas. It combines the advantages of transmit diversity and TCM in an ingenious way to obtain reliable, high data rate transmission in wireless channels without feedback from the receiver.

STTC was first introduced by Tarokh et al in 1998 [3]. They derived design criteria for STTC over slow flat fading, fast flat fading and spatially correlated channels assuming high SNRs. They constructed codes that provided a good trade-off between data rate, diversity advantage, and trellis complexity.

Some of the seminal literature on STTC is listed below.

References 

[1] Baro, S.; Bauch, G.; Hansmann, A, “Improved codes for space-time trellis-coded modulation”, IEEE Communications Letters, Volume: 4 Issue: 1, Jan. 2000 Page(s): 20 -22

[2] Firmanto, W.; Vucetic, B.S.; Yuan, J, “Space-time TCM with improved performance on fast fading channels”, IEEE Communications Letters, Volume: 5 Issue: 4, Apr 2001 Page(s): 154 -156

[3] Tarokh, V, Seshadri, N and Calderbank, A.R, “Space-Time Trellis Codes for High Data Rate Wireless Communication: Performance Criterion and Code Construction”, IEEE Transactions on Information Theory, Volume 44, No 2, March 1998.

[4] Tarokh, V.; Naguib, A.; Seshadri, N.; Calderbank, A.R., “Space-time codes for high data rate wireless communication: performance criteria in the presence of channel estimation errors, mobility, and multiple paths”, IEEE Transactions on Communications, Volume: 47 Issue: 2, Feb 1999 Page(s): 199 -207