Aspects of Control Signaling in Wireless Multiple Access Systems

Abstract: From its first appearance, wireless communications has changed thelife for many people worldwide. Currently, more than half of the world's population are using wireless devices for various purposes on a daily basis. While the early wireless systems could provide simple and specific low-rate services, today's systems can support a variety of more advanced services some of which require high data rate communications. This includes for example web-browsing and streaming multimedia applications. To meet the high demands on the current systems, many technical solutions have been proposed. Many of these solutions are powerful in the sense of boosting the system performance, but on the other hand, they impose a substantial control signaling overhead on the system. The control signaling refers to sending the control information that is necessary to establish and/or maintain the connection as opposed to the payload data that is transmitted during the connection.In this thesis, we are interested in evaluating the relations between the gain of deploying new techniques and the amount of control signaling overhead they incur. Moreover we are interested in finding efficient algorithms that can potentially reduce the control signaling overhead. More specifically, we first focus on the part of the control signaling overhead that concerns sending the scheduling assignments that describe how the channel resources are allocated among the users. We compare two ways for the signaling of scheduling assignments and we will study how different parameters such as scheduling granularity impact the control signaling overhead. We also provide two schemes that reduce the control signaling overhead substantially. We then provide an algorithm for fast blind identification of channel codes. This algorithm is very useful in improving the so-called blind decoding performance. This is essential since blind decoding is used to achieve adaptive modulation and coding in the control channel of some of the wireless communication systems such as 3GPP Long Term Evolution.