Measurement of indoor channel characteristics at 20 GHz band

A high frequency (over 6 GHz) band 5G system with a very high data transmission rate has been the focus of studies recently. One important issue to enable this system is clarifying the propagation characteristics at high frequency (over 6 GHz) bands. This paper presents the channel characteristics at the 20 GHz band for an indoor office environment. Measurements are performed using a channel sounder at the 20 GHz band with a 50-MHz-bandwidth orthogonal frequency-division multiplexing signal. A 19 dBi horn antenna is rotated in azimuth and elevation on the receiver side in order to measure the Power Delay Profile (PDP) at each angle. By combining all the PDPs, the channel characteristics are estimated as if using an omni-directional antenna. The measured and estimated results show that the path loss values are lower than those in free space. The averages of the delay spread, azimuth angle spread, and elevation angle spread are 60.4 ns, 64.7 degrees, and 3.6 degrees, respectively. The standard deviations of the delay spread, azimuth angle spread, and elevation angle spread are 9.7 ns, 10.7 degrees, and 3.1 degrees, respectively.