Improved design criteria and new trellis codes for space-time coded modulation in slow flat fading channels

• Published in: IEEE communications letters Vol. 5; no. 7; pp. 313 - 315
• Main Authors: Meixia Tao, Cheng, R.S.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.07.2001; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Channels; Computer simulation; Convolutional codes; Criteria; Derivation; Diversity methods; Exact sciences and technology; Fading; Information, signal and communications theory; MIMO; Modulation; Modulation coding; Modulation, demodulation; Rayleigh channels; Receiving antennas; Signal and communications theory; Signal to noise ratio; Slot antennas; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Transmitting antennas; Trellis codes; Performance evaluation; MIMO system; Error probability; Simulation; Coding; Rayleigh channels; Diversity; Signal processing; Trellis code; Space time; Digital transmission
• ISSN: 1089-7798; 1558-2558
• DOI: 10.1109/4234.935753

The design criteria for space-time codes under slow flat Rayleigh fading environments are well known to be the rank criterion and the determinant criterion. However, the derivation of these two criteria is based on the assumption that the signal-to-noise ratio (SNR) is sufficiently high. Hence these criteria are loose when the SNR does not satisfy this assumption. In this letter, we consider this practical issue and derive tighter design criteria for moderate and low SNRs. Some new space-time trellis codes are found based on the new criteria through computer search. Simulation results show that these codes outperform existing codes under their designed SNR conditions.