NTT DOCOMO and Rohde & Schwarz have joined forces set up what is said to be the world's first ultra-wideband channel sounder for mobile communications exceeding 100GHz. They conducted radio wave propagation experiments at frequencies up to 150GHz.
The frequency bands from 100GHz to 300GHz are expected to enable further high-speed and large-capacity communication for the next generation beyond 5G.
In the experiments, DOCOMO and Rohde & Schwarz measured and analysed the effects of radio wave propagation characteristics and shielding effects in the mmWave range.
As a result, the two companies pioneered new frequency bands and contributed to the realisation of terabit-class mobile communication systems.
In the 100GHz to 300GHz frequency bands, wider bandwidths are available than in the ones used for 5G.
However, these higher mmWave frequency bands are strongly affected by persons, vehicles, trees and environmental conditions like rain.
It is therefore necessary to research the influence of such objects on the radio wave propagation characteristics.
Using test and measurement equipment from Rohde & Schwarz, DOCOMO has developed a novel ultra-wideband mmWave band channel sounder to measure radio wave propagation characteristics necessary for evaluating mmWave mobile communication systems exceeding 100GHz.
The measurement parameters include the propagation loss (degree of attenuation of radio waves), power delay profile (arrival time of radio waves), angular profile (indicator of spread of radio wave arrival).
In the test system the R&S SMW200A signal generator together with the R&S SMZ frequency multiplier generate the mmWave signal, while the R&S FSW85 signal and spectrum analyser equipped with the R&S FS-Z170 harmonic mixer analyse it with a scalable analysis bandwidth of up to 2GHz.
The setup offers a highly convenient user interface with a high resolution multi touch display directly displaying the radio wave propagation characteristics in real-time.
In this experiment, this test system was placed in an anechoic chamber. DOCOMO and Rohde & Schwarz confirmed that they can measure and analyse the shielding effect of the human body, applying signals up to 150GHz and in all common 5G frequency bands currently in use or under consideration.