A virtual MIMO framework for multipath fading channels

We develop a virtual MIMO (multiple input multiple output) framework for characterizing single-transmitter single-receiver multipath channels. We arrive at four different MIMO channel models depending on the basis functions used to characterize the signal space dimensions. The MIMO representation reveals the relation between the factors that affect system performance and facilitates transceiver design. Specific transceiver structures are represented by special cases of the MIMO models. The framework makes it possible to determine closed form expressions for ergodic and outage capacity for a variety of transceivers. A simple transceiver is proposed that transforms the multipath channel into a virtual multiple antenna array system to which space-time codes can be directly applied.