Proposal of the Project for Wireless Communication
Project Name:
Power Allocation for Downlink Non-Orthogonal Multiple Access Systems
using Convex Optimization
members: XIAO Weihua (肖伟华) 15010180034
CHAI Jingxuan (柴靖轩) 15010180033
Ⅰ. Research Background
The fifth generation (5G) communication systems is on its way. It is widely believed that 5G is not just an incre-mental version of the fourth generation (4G) communication systems due to the increasing demand of internet-of-things (IoT), data traffic explosion, cloud-based applications, etc. These applications and services pose challenging requirements for 5G wireless communication systems, such as much higher data rates (100~1000 times than data rate of 4G technology), massive connectivity, lower latency and support of diverse quality of service (QoS) [4].
In order to meet the aforementioned challenges, some merging technologies, which are also the key technologies of current 5G technology, like millimeter wave, massive multiple-input-multiple-output (MIMO) and full duplex technologies, have been studied extensively. In contrast to conventional orthogonal multiple access (OMA), the non-orthogonal multiple access (NOMA) has been brought up, which intends to share the degrees of freedom (DoF) among users via superposition, due to the limited degrees of DoF, increasing the data rate of current 5G systems using OFDMA [1] at the same time.
Ⅱ. Significance of Research Topic
We have mentioned in part Ⅰthat NOMA can address the problem of limited DoF. Additionally, according to [1], NOMA performs better than OFDMA in data rate of downlink transmission under the circumstances of bot-h high and low SNR. Thus, although the complexity of the system increased, it's neccessary to apply NOMA in current 5G network and optimize the power allocation of NOMA under different performance criteria, like fair-ness, sum rate and energy efficiency, etc
Ⅲ. Main Contents
We propose two performance criteria, the maximin fariness (MMF) [4] and sum rate [5].
Our work is to transform these given two criteria into optimization math problems and obtain the solutions, which means obtaining the optimal power solution for NOMA system.
We will also make simulations to contrast the performance of given criteria for OFDMA system, NOMA system and NOMA system with optimized power allocation, having obtained the solution of former optimzation probl-ems. By analyzing the increment of the performance, we can find the performance gain obtained by optimizat-ion.
Ⅳ. Project Plan
1. Transform the optimization of given performace criteria into optimization problems.Decompose or transform the problem into a convex problem if the it is non-convex.
2. Obtain the solution using convex optimization.
3. Design algorithms to realize the optimization.
4. Design simulation programs to contrast the performance of given criteria for OFDMA system, NOMA system and NOMA system with optimized power allocation.
5. Analyze the result and find the increment of optimzed NOMA system than normal NOMA and OFDMA system.
Ⅴ.References
[1]Y. Saito, Y. Kishiyama, A. Benjebbour, T. Nakamura, A. Li, K. Higuchi, "Non-orthogonal multiple access (NOMA) for cellular future radio access", Proc. IEEE VTC, Dresden, Germany, Jun. 2013, pp. 1-5.
[2]Z. Wei, J. Yuan, D. W. K. Ng, M. Elkashlan, Z. Ding, "A survey of downlink non-orthogonal multiple access for 5G wireless communication networks", [Online]. Available: http://arxiv.org/abs/1609.01856.
[3]Y. Saito, A. Benjebbour, Y. Kishiyama, Y. Nakamura. "System-level performance evalulation of downlink non-orthogonal multiple access (NOMA)", IEEE Saito etal NOMA, 2013.
[4]J. G. Andrews et al. , "What will 5G be ?", IEEE J. Sel. Areas Commun. , vol. 32, no. 6, pp. 1065-1082, Jun. 2014.
[5]V. Jungnickel et al. , "The role of small cells, coordinated multipoint, and massive MIMO in 5G", IEEE Commun. Mag. , vol. 52, no. 5, pp. 44-51, May 2014.
[6]S. He, Y. Huang, J. Wang, L. Yang, W. Hong, "Joint antenna selection and energy-efficient beamforming design", IEEE Signal Process. Lett. , vol. 23, no. 9, 1165-1169, Sep. 2016.