Whenever size, power, or other constraints preclude the use of multiple transmit antennas, wireless systems cannot benefit from the well-known advantages of space-time coding methods. Cooperation between wireless users has been proposed as a means to provide transmit diversity in the face of this limitation. Cooperation involves two single-antenna users forming a partnership, in which each achieves diversity by using their partner's antenna as a relay. Previously proposed user cooperation methods involve a user repeating in some form the symbols transmitted by its partner. In this dissertation, we present a new paradigm for cooperative communication: coded cooperation . A significant departure from previous methods, coded cooperation integrates user cooperation with channel coding. Instead of repeating some form of the received information, the user decodes the partner's transmission and transmits additional parity symbols (e.g. incremental redundancy) according to some overall coding scheme. This framework maintains the same information rate, code rate; bandwidth, and transmit power as a comparable non-cooperative system. To characterize performance, we develop analytical bounds for bit and block error rates, which are confirmed by simulations. In addition, we develop outage probability expressions for non-ergodic fading, which show that coded cooperation achieves full diversity (i.e., diversity order two for two cooperating users). Finally, we extend the coded cooperation framework to a multi-user (i.e., ad hoc) network, and consider both distributed and centralized protocols for partner assignment and cooperation.
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