TY - GEN
T1 - An enhanced zero-forcing equalizer for combinerless LINC-OFDM systems
AU - Cheng, Sheng Lung
AU - Wu, Wen-Rong
AU - Hsu, Ying Pei
PY - 2014/6/25
Y1 - 2014/6/25
N2 - The energy efficiency of OFDM systems is known to be low due to the high peak-to-average power ratio problem. The linear-amplification-with-nonlinear-component (LINC) technique can solve the problem by decomposing the input signal into two constant-envelop component signals and applying high-efficient nonlinear amplifiers. However, the power combiner, a key component used to combine the amplified signals, is difficult to implement. Combinerless LINC systems employ two transmit antennas such that two component signals can be naturally combined at the receiver. Unfortunately, the performance of combinerless LINC-OFDM systems is seriously degraded if difference exists, even small, between the two channels that the two component signals propagate. In this paper, we propose an enhanced zero-forcing equalizer to solve this problem. The main idea is to reduce a self-interference induced by the channel difference. A closed-form expression for the optimum parameter of the proposed equalizer is also derived. Simulations show that the proposed equalizer can effectively enhance the performance of combinerless LINC-OFDM systems.
AB - The energy efficiency of OFDM systems is known to be low due to the high peak-to-average power ratio problem. The linear-amplification-with-nonlinear-component (LINC) technique can solve the problem by decomposing the input signal into two constant-envelop component signals and applying high-efficient nonlinear amplifiers. However, the power combiner, a key component used to combine the amplified signals, is difficult to implement. Combinerless LINC systems employ two transmit antennas such that two component signals can be naturally combined at the receiver. Unfortunately, the performance of combinerless LINC-OFDM systems is seriously degraded if difference exists, even small, between the two channels that the two component signals propagate. In this paper, we propose an enhanced zero-forcing equalizer to solve this problem. The main idea is to reduce a self-interference induced by the channel difference. A closed-form expression for the optimum parameter of the proposed equalizer is also derived. Simulations show that the proposed equalizer can effectively enhance the performance of combinerless LINC-OFDM systems.
KW - Linear-amplification-with-nonlinear-component (LINC)
KW - orthogonal frequency division multIPlexing (OFDM)
KW - peak-to-average power ratio(PAPR)
UR - http://www.scopus.com/inward/record.url?scp=84944320235&partnerID=8YFLogxK
U2 - 10.1109/PIMRC.2014.7136273
DO - 10.1109/PIMRC.2014.7136273
M3 - Conference contribution
AN - SCOPUS:84944320235
T3 - IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC
SP - 795
EP - 799
BT - 2014 IEEE 25th Annual International Symposium on Personal, Indoor, and Mobile Radio Communication, PIMRC 2014
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2014 25th IEEE Annual International Symposium on Personal, Indoor, and Mobile Radio Communication, IEEE PIMRC 2014
Y2 - 2 September 2014 through 5 September 2014
ER -
