System Level Performance Evaluation of 60 GHz Downlink under Different Beamforming and Scheduling Methods

Abstract

The research in millimeter-wave (mm-wave) area is of special interest to the upcoming fifth generation (5G) communications. The 60 GHz band is one of the most attractive 5G bands. That is due to the abundantly available spectrum, higher achievable throughput, and lower latency when compared to the conventional 4G bands. This research addresses the 60 GHz system level performance evaluation for cellular downlink transmission in an outdoor environment. Using a custom system level simulator, different parameters associated with the mm-wave communication system are predicted. These parameters include path loss (PL), signal-to-noiseplus-interference-ratio (SINR), number of antenna elements and several arrays implementations. Taking into consideration the effect of multipath fading, two packet scheduling algorithms are exploited, namely maximum rate (Max C/I) and Round Robin (RR). The performance is evaluated under various phased antenna configurations at both transmitter and receiver sides. An urban femtocells environment with both 25 m and 50 m hexagonal cell radii is considered for performance evaluation. At 60 GHz operating frequency, allocation of the radio resources is not standardized. Therefore, different implementations can be tested to find how good a specific scheduler is under the same conditions of the propagation channel. The system design, beamforming technique, phased arrays implementations, scheduling algorithms and simulator findings are described in details in this work. From the simulation results, we conclude that scheduling scheme, beamforming and antenna array design play an essential role to offset the effect of fading and interference. Results illustrate that the performance variation between the two scheduling algorithms is relatively small. Antenna element selectivity has a huge impact on system performance. Also, the importance of steering plane is unequal in the case of cellular downlink transmission.