This blog is by Harri Holma of the Nokia Siemens Networks Radio research team in Finland.
It has been a couple of years since Nokia Siemens Networks started to use the term Smart Scheduler in the context of LTE. The scheduler is the piece of software within the base station that allocates frequency resources to the users of a radio cell. A smart implementation of the scheduler is therefore essential to deliver high data rates and high cell capacity. This is exactly where the Nokia Siemens Networks Smart Scheduler has been making a difference in actual network performance since 2010.
Scheduling algorithms have not been defined in 3GPP. They are vendor specific, so there is some room for confusion about differing terminology and assumptions about gains.
With the new Nokia Siemens Networks whitepaper “LTE: Smart Scheduler” we aim to create common ground for meaningful discussions about scheduling in LTE. In particular we discuss the function and benefits of various features such as Frequency Selective Scheduling (FSS), which a truly Smart Scheduler must provide. Architectural alternatives, such as distributed and centralized approaches, are compared, taking into account related backhaul requirements as well as the standardization required for related interfaces.
The whitepaper also provides a preview of the future of scheduling in LTE and LTE-Advanced. For example, the implicit coordination via FSS will be complemented by explicit coordination in multi-cell and HetNet environments. The X2 interface will evolve to the enhanced X2+ interface, and centralized architectures in multivendor environments will require the standardization of a new X3 interface. It also covers a new study item on enhanced CoMP for LTE, which was initiated in June 2013 as part of 3GPP, and aims to evaluate the benefits of multi-cell scheduling with non-ideal backhaul.
With our new whitepaper we aim to provide a concise and compact overview of the complex topic of scheduling in LTE. We hope you enjoy reading it.