MIMOjärjestelmien

MIMOjärjestelmien, which stands for Multiple-Input Multiple-Output systems, is a wireless communication technology that utilizes multiple antennas at both the transmitter and receiver. This spatial diversity allows for significant improvements in data throughput and link reliability. By transmitting different versions of the same data stream, or entirely different data streams, across multiple antennas, MIMO systems can exploit the spatial dimension to overcome limitations imposed by fading and interference.

The core principle behind MIMO is the creation of independent spatial channels. When signals are transmitted from multiple antennas and arrive at multiple receiver antennas, they take different paths through the environment. These multipath propagation effects, which are typically detrimental in single-antenna systems, can be leveraged by MIMO to create distinct channels. Signal processing techniques are then employed at the receiver to separate these individual streams, effectively increasing the overall data rate.

There are several key techniques within MIMO. Spatial Multiplexing, for instance, sends independent data streams from each transmit antenna, thereby increasing spectral efficiency. Space-Time Coding combines spatial and temporal coding to improve error resilience, while transmit diversity techniques send redundant copies of the data across antennas to enhance robustness against fading. MIMO systems are a fundamental component of modern wireless standards such as Wi-Fi (802.11n, 802.11ac, 802.11ax) and cellular technologies (4G LTE, 5G NR), contributing significantly to their enhanced performance and capacity.