LTE Advanced: 3GPP Solution for IMT-Advanced

12.4 Machine Type Communications

One of the interesting areas being worked at in 3GPP TSG RAN is the features for the support of Machine Type Communications (MTC). This type of communications does not require human interaction and can be viewed as data communications between devices and a server, or device to device. Some examples of MTC services include sensors, security and public safety, tracking, payment, monitoring, remote managements and diagnostics, and smart grid. Typical characteristics of machine type communications include low cost, low mobility, delay tolerant, large number of devices, small and infrequent data transmission, high reliability, time-controlled operation and group-based communications.

With the widespread introduction of LTE and decommissioning of legacy systems, migration of MTC devices to LTE is under investigation by cellular operators. To ensure that there are no coverage holes with such migration, LTE must provide the same or larger system coverage compared to legacy systems such as GSM or UMTS. This will allow LTE deployment using existing cellular sites. Typically, system coverage is limited by the uplink due to the limited transmission power of the device. Table 12.2 provides uplink link budget comparison of LTE to several cellular systems (UMTS, CDMA1x, and GSM) that are currently used for machine type communications [4]. From the Table 12.2, it is seen that LTE provides comparable link budget to existing cellular systems. Thus, the coverage hole ...