1. Submission doc.: IEEE 802.11-15/0097r0 Slide 1 Performance Analysis of Frequency Selective Scheduling Date: 2015-01-12 Authors: Ningbo Zhang, BUPT January 2015 NameAffiliationsAddressPhoneEmail Ningbo Zhang Beijing University of Posts and Telecommunicati ons Beijing, Chinanbzhang@bupt.edu.cn Guixia Kang Beijing University of Posts and Telecommunicati ons Beijing, Chinagxkang@bupt.edu.cn

2. Submission doc.: IEEE 802.11-15/0097r0 Abstract Background Evaluation methodology Simulation Parameters Performance comparison Conclusions Slide 2 Ningbo Zhang, BUPT January 2015

3. Submission doc.: IEEE 802.11-15/0097r0 Background OFDMA is a positional technology to increase the spectral efficiency in 802.11ax Frequency selective scheduling is allowed in OFDMA systems The gain of frequency selective scheduling depends on: –Scheduling algorithm –Number of users –Radio environment –Channel estimation –Channel state information(CSI) reporting delay In this contribution, we study the performance of frequency selective in fading channels Slide 3 Ningbo Zhang, BUPT January 2015

4. Submission doc.: IEEE 802.11-15/0097r0 Evaluation methodology Scheduling algorithms Single user Algorithm 1: one user transmits data packet on the fixed subband Algorithm 2: one user transmits data packet on a random subband Algorithm 3: Frequency selective scheduling, one user transmits data packet on the best subband Multiple Users Algorithm 1: multiple users transmits data packets on the fixed subbands Algorithm 2: multiple users transmits data packets on a random subbands Algorithm 3: Frequency selective scheduling, users are allocated to suitable subbands to transmit data packets Slide 4 Ningbo Zhang, BUPT January 2015

5. Submission doc.: IEEE 802.11-15/0097r0 Simulation Parameters Slide 5 Bandwidth: 20MHz Number of STA: 4 MCS selection: MCS to achieve highest throughput Channel estimation: MMSE CSI feedback: Perfect CSI feedback Channel model: EPA Ningbo Zhang, BUPT January 2015

6. Submission doc.: IEEE 802.11-15/0097r0 Performance comparison for single user Slide 6 The performance of random selective subband is similar with fixed subband. Frequency selective subband shows large performance gains compared with random subband and fixed subband. Ningbo Zhang, BUPT January 2015

7. Submission doc.: IEEE 802.11-15/0097r0 Performance comparison for multiple users Slide 7 The performance of frequency selective subband outperforms fixed subband and random subband The throughput gain of multiple user is smaller than that of single user. Ningbo Zhang, BUPT January 2015

8. Submission doc.: IEEE 802.11-15/0097r0 Conclusions The performance of random selective subband is similar to the performance of fixed subband. Frequency-selective scheduling can provide gain for both single user and multiple user cases. The performance gain of single user is larger than that of multiple users. The inaccurate CSI feedback may lead to scheduling performance loss, but need further study. Slide 8 Ningbo Zhang, BUPT January 2015

9. Submission doc.: IEEE 802.11-15/0097r0 References [1]11-14/0858r0, “Analysis on Multiplexing Schemes exploiting frequency selectivity in WLAN Systems” [2] 11-14/1227r3, “OFDMA Performance Analysis” [3] “LTE Frequency Selective Scheduling Performance and Improvements Assessed by Measurements”, IEEE 22nd International Symposium on Personal, Indoor and Mobile Radio Communications, 2011. Slide 9 Ningbo Zhang, BUPT January 2015