Construction of High Rate Super-Orthogonal Space-Time Block Codes

It is standard practice to integrate outer trellis codes with inner space-time block codes to increase coding gain, but the drawback is a decrease in rate. Jafarkhani and Seshadri [1] have introduced an alternative method of combining multiple inner orthogonal space-time codes with outer trellis codes that both preserves rate and increases coding gain. However their work is limited to orthogonal codes, for which the achievable rate is typically low. This paper presents a method of achieving higher transmission rates by integrating higher rate non-orthogonal space with outer trellis codes, and new methods are introduced to avoid catastrophic codes. The method is presented with reference to the particular example of the Silver Code, but it applies to all multiplexed orthogonal designs and to more general codes.