Channel measurement and characterisation for 5G multi-scenarios at 26 and 38 GHz

Millimetre-wave (mmWave) frequencies play a vital role in fifth-generation (5G) wireless systems and beyond due to the vast available bandwidth of several GHz. This paper presents channel characteristics and their channel models for mmWave based on extensive channel measurements at 26 and 38 GHz conducted in 5G scenarios, such as the rooftop, the high-speed railway, and the Industrial Internet of Things scenarios. The channel sounder receiver (Rx) uses an omnidirectional or phased array antenna to meet the requirements of channel measurement, such as recording absolute delay and obtaining 3-dimensional angular information. We use the classical close-in model and floating-intercept model to model path loss. Meanwhile, channel statistics in the delay domain are derived from the measured power delay profiles. Note that the different scenarios are measured with the same channel sounder, making the measurement results of different scenarios comparable. It is shown that the shadow fading parameter σ is 0.7 dB as fewer large scatterers exist in the rooftop scenario. Moreover, due to the significant dependence of delay spread on the geometric relationship between the transmitter (Tx), Rx, and surrounding environment, the statistical data in the delay domain varies significantly in different scenarios. The channel characteristics and models will guide future air-interface, beamforming, and transceiver designs for 5G and beyond.