The 3rd Generation Partnership Project (3GPP) long term evolution (LTE) system, introduced as 3GPP release 8, is an improved universal mobile telecommunication system (UMTS). An LTE system offers high peak data rates, low latency, improved system capacity, and low operating cost resulting from simple network architecture. In the LTE system, an evolved universal terrestrial radio access network (E-UTRAN) includes a plurality of evolved Node-Bs (eNBs) communicating with a plurality of mobile stations, referred as user equipment (UE). 3GPP introduces new features to help LTE system operators to further optimize network planning in a cost-effective way. Minimization of Drive Test (MDT) is one of the features where UEs collect measurements and report measurement information to their serving eNBs.
MDT has been worked on in 3GPP to help with network optimization. Network optimization is traditionally done by manual drive testing, which is costly and causes additional CO2 emissions. The essence of MDT feature is to provide for normal mobile terminals the possibility to record and log information relevant to the radio communication of the mobile terminals, correlated with the geographical location of the mobile terminals. MDT feature enables UEs to perform Operations, Administration, and Maintenance (OAM) activities, such as neighborhood detection, measurements, logging and recording for OAM purposes, which includes radio resource management (RRM) and optimization purposes.
While studying the possible scope of minimization of drive test (e.g., 3GPP TR 36.805), it has been found beneficial to include Quality of Service (QoS) measurements for MDT, and in particular a throughput measurement. It is assumed that it would be desirable to as much as possible mimic manual drive testing. It would be desirable to provide the possibility to measure throughput, and while the UE pass through a network doing frequent handovers. Note that it is expected that frequent handover may affect TCP performance and lead to reduced user-experienced throughput.
Several definitions of throughput measurements exist in 3GPP TR36.314, TR 32.425, and TR 32.451. However, there is no definition supports well all the MDT requirements. It is an objective of the current invention to propose a throughput measurement definition, which fulfills well all the MDT requirements with minimum complexity.