VOL. 11, NO. 13, JULY 2016 ISSN 1819-6608
ARPN Journal of Engineering and Applied Sciences
©2006-2016 Asian Research Publishing Network (ARPN). All rights reserved.
www.arpnjournals.com
8216
AN EFFICIENT POWER CONTROL DETECTION SCHEME FOR MIMO
TRANSMISSION IN LTE
Vanitha Rani Rentapalli, Sowjanya B. and B. T. P. Madhav
Department of Electronics and Communication Engineering, K L University, AP, India
E-Mail: btpmadhav@kluniversity.in
ABSTRACT
In this paper author’s proposed an efficient ordering scheme for interference cancellation, which is determined for
multiple antenna systems using transmission power control. Based on this approach, the fixed ordering algorithm is first
designed, for which the geometric mean is used for channel gain coverage. Simulation results shows that proposed
ordering schemes using QR-decomposition require a reduced computational complexity results with improved error
performance. In this article an overview of power control in LTE uplink MIMO schemes including receivers suitable for
uplink MIMO are also presented, and their link performances are compared.
Keywords: detection ordering, MIMO, OSIC, power allocation, QR-decomposition.
INTRODUCTION
Global System for Mobile Communications
(GSM) has evolved into Enhanced Data Rates for GSM
Evolution (EDGE), while on top of these Wideband Code
Division Multiple Access (WCDMA) technology is
introduced, evolving into networks such as High Speed
Packet Access (HSPA).
Long Term Evolution (LTE) is a system currently
under standardization. It has the goals of achieving peak
data rates of 100 Mbps in downlink (DL) and 50 Mbps in
uplink (UL). The ambitious data rate target of the 4th
generation mobile communication systems can only be
achieved by using an efficient air interface advanced
Multiple Input Multiple Output (MIMO) antenna
techniques, and wide spectrum allocation for high data rate
transmissions. The goal of power control is to transmit at
the right amount of power needed to support certain data
rate. Too much power generates unnecessary interference,
while too little power results in an increased error rate
resulting in larger transmission delays and lower
throughputs. MIMO system is practical transreceiver
implementation for their great potential of enhancing the
system performance. Data stream with smallest SINR
(Signal to Interference Noise Ratio) degrades the overall
error performance so an attractive system is designed for
enhancing the system performance is B-OSIC (BLAST
Ordered Successive Interference Cancellation). The
computational complexity and feed back overhead is
decreased by adopting the PA (Power Allocation) scheme
with B-OSIC receiver. In this paper BER (Bit Error Rate)
minimization condition is derived from the convexity of
the Q-function in the PA scheme. This scheme is
adaptively updates the threshold to conform the superiority
of the adaptive design. The performance of a number of
receivers for UL data channel is evaluated using link
simulations, which shows that significant performance
gain is achievable when an advanced receiver such as the
turbo equalization receiver is used at the eNB (eNodeB).
This paper investigates in detail about how the
power control detection scheme in MIMO based systems
support certain data rate. Section II describes the average
interference level received at eNB is reduced by
performing slow power control in UE Uplink
transmission. The PA scheme for average BER
minimization can be obtained from QR decomposition is
explained Section III, Performance evaluation is discussed
in section IV, simulation results have been shown in V,
and finally section VI provides conclusion for this paper.
[1-3]
LTE-Uplink power control
The cellular systems are generally coverage
limited in the uplink due to limited UE transmit power.
The LTE uplink uses orthogonal (Single Carrier-
Frequency Division Multiple Access) SC-FDMA high
levels of interference from neighbouring cells can limit the
uplink coverage if UEs in the neighbouring cells are not
power controlled. Power control is responsible for
managing the transmitting (Power Spectral Density) PSD
of each user. By performing the slow power control
scheme on each UE uplink transmission power, the
average inter-cell interference level received at the
eNodeB is effectively reduced.
Uplink power control for LTE is the set of
algorithms and tools by which the transmit power for
different uplink physical channels and signals are
controlled are received at the cell site with appropriate
power. This means that the transmission should be
received with sufficient power to allow for proper
demodulation of the corresponding information. Power
control is responsible for managing the transmitting PSD
of each user.
In LTE-UL SC-FDMA introduces (Inter Symbol
Interference) ISI in dispersive channels. Thus, a desired
MIMO receiver should address both ISI and spatial-
multiplexing interference. Link simulation results are
provided to demonstrate the performance of UL data
channel and also compare the