Article,
Mobiles Energy Consumption in LTE Uplink Networks
Int. J. on Recent Trends in Engineering and Technology,, 10 (2): 13 (January 2014)
Abstract
3GPP has standardized different multicarrier access methods in the downlink
and uplink for LTE. While Orthogonal Frequency Division Multiple Access (OFDMA) is
chosen in the downlink, Single Carrier Frequency Division Multiple Access (SC-FDMA) is
chosen in the uplink due to its low Peak-to-Average Power Ratio (PAPR) which plays a
crucial role in the User Equipment’s (UE) power consumption. This paper presents two set
of analysis- first being the performance and comparison of Best-Effort Resource Block (RB)
Scheduling algorithms based on the Resource Block usage ratio and their impact on the
overall throughput. The second is to determine the Signal-to-Interference-plus-Noise Ratio
(SINR) per RB per UE. As the SINR at any instant is directly proportional to the power of
the UE/RB, under this assumption the UE/RB power can be reduced. Based on the
minimum SINR/UE/RB that can be achieved, the power control is then introduced on each
of the UE/RB to obtain the least possible power for transmitting the data while maintaining
the throughput. A Channel Quality Indicator (CQI) table is used as a reference to obtain the
new SINR for each UE/RB. The difference between the new and the old SINR is calculated
which gives the amount by which the UE/RB power can be reduced without affecting the
throughput. The results obtained show a reduction in the power consumption by upto 28%.
