Comparison Analysis of Outdoor Channel Characteristics at 28 GHz and 2 GHz Using 3D Ray-Tracing Technique

Broadband wireless systems operating in millimeter wave (mmWave) frequency band has been used for short-range wireless communication and point-to- point wireless backhaul. Due to lack of research work on outdoor radio propagation characteristics in mmWave frequency band, the question of feasibility of cellular communication including long-range and non-line of sight (NLoS) environments in mmWave frequency band is unanswered. In this paper, we investigate the radio propagation characteristics at 28 GHz and 2 GHz using 3D ray-tracing simulation based on Manhattan-like grid model. LoS and NLoS results of outdoor radio propagation characteristics considering beamforming effects at 28 GHz are provided. Results of 2 GHz in the same geometry are also provided. In LoS environment, the radio propagation with 25 dBi beamforming gain at 28 GHz has similar characteristics with 2 GHz. In NLoS environment, even if the transmitter has 25 dBi beamforming gain at 28 GHz, the received power is 10 to 25 dB lower than 2 GHz. The received power loss because of narrow beam usage at 28 GHz is negligible in both LoS and NLoS environments.