dietcha
2012-06-15, 08:17 PM
Single Carrier Frequency Division Multiple Access (SC-FDMA) is the access
scheme chosen by 3GPP for uplink UTRAN Long Term Evolution project.
As SC-FDMA provides intra-cell orthogonality, one of the main reasons for
performance degradation is the inter-cell interference.
This degradation is accentuated by the frequency reuse factor of 1 deployed in
the system, which makes the Power Control (PC) functionality a critical issue.
Recently, a PC formula containing an open loop and a closed loop component
has been standardized. The open loop power control (OLPC) compensates
for slow varying pathloss and shadowing, while the closed loop power control
(CLPC) implementation is vendor specific and still under research. It allows
to compensate for fast variations and manage the interference.
In this thesis, the OLPC is studied in detail to obtain a reference performance,
then two CLPC techniques are proposed with the aim of improving it. All
techniques are implemented on a static simulator that models slow variations.
The comparison of the result among the different techniques is carried out by
considering key performance indicators like the cell outage and cell throughput
The results show a gain compared to the OLPC of up to 22 % of in outage
user throughput with a 5 % in cell. Alternatively, it is possible to tune the
parameters of the proposed techniques to obtain more gain in cell at the cost
of a reduction of the gain in outage.
http://projekter.aau.dk/projekter/files/14523970/Advanced_Power_Control_for_UTRAN_LTE_UL.pdf
scheme chosen by 3GPP for uplink UTRAN Long Term Evolution project.
As SC-FDMA provides intra-cell orthogonality, one of the main reasons for
performance degradation is the inter-cell interference.
This degradation is accentuated by the frequency reuse factor of 1 deployed in
the system, which makes the Power Control (PC) functionality a critical issue.
Recently, a PC formula containing an open loop and a closed loop component
has been standardized. The open loop power control (OLPC) compensates
for slow varying pathloss and shadowing, while the closed loop power control
(CLPC) implementation is vendor specific and still under research. It allows
to compensate for fast variations and manage the interference.
In this thesis, the OLPC is studied in detail to obtain a reference performance,
then two CLPC techniques are proposed with the aim of improving it. All
techniques are implemented on a static simulator that models slow variations.
The comparison of the result among the different techniques is carried out by
considering key performance indicators like the cell outage and cell throughput
The results show a gain compared to the OLPC of up to 22 % of in outage
user throughput with a 5 % in cell. Alternatively, it is possible to tune the
parameters of the proposed techniques to obtain more gain in cell at the cost
of a reduction of the gain in outage.
http://projekter.aau.dk/projekter/files/14523970/Advanced_Power_Control_for_UTRAN_LTE_UL.pdf