4-PSK Balanced STTC with Two Transmit Antennas
In this paper we introduce a new class of space-time trellis codes (STTC). We call them balanced STTC (B-STTC) because the points of the constellation are used with the same probability. Comparing to known codes, the balanced codes offer the best performance. Therefore, the systematic search for good codes can be reduced to this class. We present here the design of the 4-PSK balanced STTC with 2 transmit antennas. A complete list of the best 4-state and several 16-state good balanced codes are also given.