Chapter 9 - The IEEE 802.16m Physical Layer (Part I)

Abstract

A good and robust design of the physical layer ensures that the system can normally operate and can provide the maximum throughput and lowest latency under various operating conditions. The physical layer processes both control- and data-plane signals; however, due to different design requirements and reliability and performance criteria, the procedures tend to be different. The physical layer of the IEEE 802.16m is based on the IEEE 802.16-2009 standard, there are new or modified functional components that contribute to significantly increased performance of the IEEE 802.16m relative to the legacy standard. During the design of IEEE 802.16m, an attempt was made to identify the shortcomings of the legacy standard and to replace the inefficient protocols with new or improved procedures. In some cases, such as frame structure, subchannelization and permutation, and control signaling, there have been great changes from the corresponding legacy frameworks which make the mixedmode operation of the new and legacy systems more complex. However, extreme modifications were necessary to fulfill the IMT-Advanced requirements and to allow future enhancements of the radio air interface. The main criteria in the design of the new physical layer were to increase the application throughput and capacity, reduce access latency, support higher user mobility, minimize intracell and intercell interference, improve reliability of control and data channel coverage (especially at the cell edge), and reduce the complexity and signaling overhead.