Single-Input and Single-Output (SISO) is a part of MIMO systems with one transmit antenna and one receive antenna, while MIMO can have more than one transmit antennas and more than one receive antennas.

## System Model Edit

In wireless cellular networks, the received signal in SISO is given by

- $ y_k = P_k h_k x_k + n_k $

where $ P_k $ is the transmit power, $ h_k $ is the scalar fading wireless channel, $ x_k $ is the scalar transmit signal, and $ n_k $ is the scalar noise signal.

## Ergodic Capacity Edit

The ergodic capacity of the SISO system is given by

- $ C = \log_2(1 + P_k |h_k|^2) $

which is achievable throughput without knowing full instantaneous channel state information.