Propagation measurement of 70-GHz band in a moving train

Abstract

SUMMARYDelay profiles at 70 GHz were acquired in a moving train. In measurement with the transmitting and receiving antennas facing with each other, it was found that the correlation between the first arriving wave level and the delay spread is high and the variation width of the first arriving wave level and the delay spread are increased compared to the values in a stationary train due to the effect of vibrations during motion. Next, in measurement with a receiving antenna oriented outward to study the effect of waves reflected from the exterior of the train, the delay spread was found not have a correlation with the first arriving wave level but to vary with the effects of the environment. An environment that affects the delay spread is metallic sign boards placed in tunnels and train stations. For each measurement parameter, the minimum and maximum values, central value, mean, and variance are presented.

Space and frequency multiplexing for MM-wave multi-gigabit point-to-point transmission links

“…Similarly to US and EU, a document issued in 2008 by the Ministry of Economic Development of Australia [3] contains some preliminary regulations on the usage of E-bands for terrestrial wireless communications (in [3], data rates of 10 Gbps over 8 km links are envisioned). In Japan, thorough studies on the radio propagation at 70 GHz have been issued since 2000 by Nippon Telegraph and Telephone Corporation (NIT) and National Institute of Information and Communications Technology (NICT) for indoor [4] [5] and outdoor mobile environments, as well as for trains [6]. These studies outlined the propagation losses in different environments, considering line-of-sight (LOS) and non-line of-sight (NLOS) fixed and mobile scenarios.…”