Super-quasi-orthogonal space-time trellis codes for four transmit antennas

Abstract

Abstract-We introduce a new family of space-time trellis codes that extends the powerful characteristics of super-orthogonal space-time trellis codes to four transmit antennas. We consider a family of quasi-orthogonal space-time block codes as building blocks in our new trellis codes. These codes combine set partitioning and a super set of quasi-orthogonal space-time block codes in a systematic way to provide full diversity and improved coding gain. The result is a powerful code that provides full rate, full diversity, and high coding gain. It is also possible to maintain a tradeoff between coding gain and rate. Simulation results demonstrate the good performance of our new super-quasi-orthogonal space-time trellis codes.

Improved super-orthogonal codes through generalized rotations

“…For this code, , . This code gives about 1 dB gain over the code given in [1], which also outperforms the code in [4] which uses a quasi-orthogonal code.…”

Impact of spatial channel correlation on super quasi-orthogonal space-time trellis codes

“…The only constraints for the rotation parameters Θ 1 and Θ 2 of the constituent QSTBCs proposed in [7] and [8] are such that they must not expand the original signal constellation. But as we have shown above, the rotation parameters essentially influence the interference parameter of the constituent codes and therefore also influence the performance of the resulting S-QSTTCs at least on spatially correlated channels.…”

“…2 that the EA-type S-QSTTC performs better than the ABBAtype S-QSTTC, because now both constituent EA-type QSTBCs have smaller mean values of X on correlated channels than the ABBA-type QSTBCs. As demonstrated in [8] the performance of an S-QSTTC can be improved using full-diversity QSTBCs with multi dimensional signal rotation. However, in this case the transmitter is more complex, because higher order symbol constellations have to be decoded.…”

“…In [8] S-QSTTC have been introduced as an extension of S-OSTTC for two transmit antennas to four transmit antennas. These S-QSTBCs can be used to obtain a new family of trellis codes which provide the diversity of the original QSTBC at full data rate and provide additional coding gain [8].…”

“…Parameterized STBCs which provide additional transmit matrices have been introduced in [7] and [8] to increase the data rate. These parameterized STBCs are called super orthogonal STBCs (S-OSTBCs) in case of 2 transmit antennas.…”