Multiple antennas increase capacity and reliability.
Multiple antennas at transmitter and receiver provide diversity gain, array gain and spatial multiplexing (capacity grows ~min(N_t,N_r) lines). Techniques: beamforming, Alamouti coding, massive MIMO in 5G with dozens of antenna elements, MU-MIMO serving users simultaneously. Needs channel estimation.
Wi-Fi 6 routers use 4×4 MIMO for multi-gigabit throughput.
MIMO uses several antennas to increase capacity and reliability, which is now standard in Wi-Fi and 5G.
Multiple antennas increase capacity and reliability.
MIMO uses several antennas to increase capacity and reliability, which is now standard in Wi-Fi and 5G.
Sending different data streams from different antennas at the same time and frequency, which increases capacity when the channel is rich in paths.
It can use the same total power, but it needs more processing and antenna space, and the gain depends on channel conditions.
Typical applications include increasing the data rate of a Wi-Fi router with multiple antennas, using spatial multiplexing to send separate streams in a dense city and improving reliability with receive diversity on a base station.
Study "Fading and multipath" first (topic 92 of 101 in Signals, Control & Comms). It covers the groundwork this topic builds on.
Spatial streams. Channel matrix H. Precoding.
Wi-Fi 6 routers use 4×4 MIMO for multi-gigabit throughput.
The next topic is "Cellular systems", which builds directly on this one.
It is classed as Advanced in Signals, Control & Comms (topic 93 of 101). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Signals, Control & Comms.
Want to practise? Open the interactive course for quick checks, quizzes, simulations and progress tracking.