  In this paper we present several strategies for multiple relay networks which
are constrained by a half-duplex operation, i. e., each node either transmits
or receives on a particular resource. Using the discrete memoryless multiple
relay channel we present achievable rates for a multilevel partial
decode-and-forward approach which generalizes previous results presented by
Kramer and Khojastepour et al.. Furthermore, we derive a compress-and-forward
approach using a regular encoding scheme which simplifies the encoding and
decoding scheme and improves the achievable rates in general. Finally, we give
achievable rates for a mixed strategy used in a four-terminal network with
alternately transmitting relay nodes.
