This study develops a new class of super-orthogonal trellis codes for four transmit antennas based on double space–time codes. The transmit antennas are divided into two groups, each having two transmit antennas. The information bits are demultiplexed into two streams; each is encoded independently using a super-orthogonal trellis code and then is transmitted from the corresponding antenna group. The resultant parallel-trellis code structure offers a higher data rate and, at the same time, it has a smaller number of parallel branches in the trellis encoder compared to a single stream encoder. The decoding is done using the maximum likelihood (ML) decoder with an interference cancellation algorithm.

It is shown that the proposed scheme reduces the required number of overall calculations by about half compared with super-orthogonal space–time trellis codes (SO-STTC) and super-orthogonal trellis coded spatial modulation (SOTC-SM).

The performance of the designed codes is simulated and shows that an improvement in the frame error rate (FER) is achieved at 4 and 5 b/s.Hz compared with SO-STTC and SOTC-SM, while at 6 b/s.Hz, it achieved an improvement in the lower and medium range of signal-to-noise ratio (SNR) ($<22$ dB).

这项研究基于双时空码为四个发射天线开发了一类新的超正交网格码。发射天线分为两组，每组都有两个发射天线。信息位被多路分解为两个流。每个都使用超正交网格码独立编码，然后从相应的天线组发送出去。所得到的并行网格编码结构提供了更高的数据速率，同时，与单个流编码器相比，其在网格编码器中具有较少数量的并行分支。使用具有干扰消除算法的最大似然（ML）解码器完成解码。

结果表明，与超正交时空网格码（SO-STTC）和超正交网格编码空间调制（SOTC-SM）相比，该方案将所需的总体计算数量减少了大约一半。

对设计代码的性能进行了仿真，结果表明，与SO-STTC和SOTC-SM相比，在4 b / s.Hz和5 b / s.Hz时，帧错误率（FER）有所提高。 ，在中低信噪比（SNR）（$<22$ D b）。