Positioning and Multimedia Broadcast/Multicast Services

In this chapter, we take a top-down systems approach to describe two important service enablers of LTE/LTE-Advanced that both started in LTE Rel-9 and have been enhanced ever since in the later releases. The UE positioning and location-based services as well as the evolved multimedia broadcast/multicast service are considered the key enablers of various services in modern cellular systems. There are numerous applications that rely on these functionalities to provide the users with the best quality of experience and ease of access to location-optimized and customized content. This chapter begins with the description of the positioning standard for LTE/LTE-Advanced systems. We review the positioning requirements, positioning architectures, and signaling. The coordinate systems and the transformations used in positioning systems are described in detail. There are many different use cases for positioning information. The positioning functions may be used internally by the EPS, value-added network services, the UE itself, or through the network by a third-party. We will then describe the E-MBMS feature in LTE/LTE-Advanced. We will review the requirements, architecture, and functional elements as well as physical and MAC layer aspects of E-MBMS. The E-MBMS bearer service is the service provided by the packet-switched domain to E-MBMS user services in order to deliver IP multicast datagrams to multiple receivers using minimal network and radio resources. An E-MBMS user service is a service provided to the end-user by means of the MBMS bearer service and possibly other EPS bearers. The E-MBMS is a point-to-multipoint service in which data is transmitted from a single source entity to multiple recipients. Transmitting the same data to multiple recipients allows the sharing of network resources. The E-MBMS for EPS bearer service supports broadcast mode over E-UTRAN and UTRAN. The E-MBMS is realized by the addition of a number of new features and new functional entities to the 3GPP network architecture. An E-MBMS counting function was introduced that allows counting the number of connected mode users that are either receiving or are interested to receive particular MBMS services. In LTE Rel-11, E-UTRAN MBMS is enhanced to ensure MBMS service continuity when multi-carrier functionality is deployed in an MBMS service area.