Development of Efficient Orthogonal Space Time Block Coding in Massive MIMO Systems

The fifth generation (5G) of wireless networks is cantered on meeting soaring data demands through innovative technologies, among which multiple-input multiple-output (MIMO) systems have emerged as pivotal. Traditional MIMO, with configurations of up to eight antennas, has significantly boosted throughput in dense urban environments without increasing spectrum or power requirements. Massive MIMO, an evolution involving dozens to hundreds of antennas, magnifies these benefits by enhancing spatial multiplexing and link reliability, thus becoming a cornerstone of 5G standards. However, this scaling introduces new challenges in hardware complexity and signal processing. A notable solution explored in this research is the enhancement of orthogonal space-time block coding (OSTBC) through the integration of Hadamard matrices. By embedding the Hadamard structure within traditional extended OSTBC, the system achieves a fourfold increase in transmitter diversity order, which directly translates to improved robustness against fading and channel impairments. Simultaneously, this approach reduces hardware complexity by enabling simpler transmitter architecture without compromising performance. Analytical derivations and simulation results corroborate the effectiveness of this strategy, suggesting that Hadamard-enhanced OSTBC can offer a practical pathway to harness the full potential of massive MIMO in 5G networks. This dual benefit of higher reliability and reduced complexity is especially pertinent as network operators seek scalable, cost-effective solutions to deploy massive MIMO at scale.