Tokyo Institute of TechnologyOn the 14th it was announced that it had developed the “Millimeter-Wave Band Step-by-Step Array Radio” that supports wireless power transmission and communication simultaneously, and passed a performance test. It is hoped that this will enable wireless power transmission and wireless communication at long distances and wide angles, and will reduce the installation cost of power repeaters for repeaters. The research was conducted by Atsushi Shiran, an associate professor at the Institute for Future Industrial Technology at the Tokyo Institute of Technology, and Kenichi Okada, a professor at the Institute of Electrical and Electronic Engineering at the Tokyo Institute of Technology.

It is used for 5G communications, etc., and when high-speed communication is possible, several repeaters have to be installed for millimeter-wave-charged waves that may be subject to interruptions. However, since the current general repeater needs to have a power source installed, there are issues such as restrictions on the repeater’s installation location and increased installation costs.

In their research, they develop the “millimeter-wave band repeater that does not require a power supply”. In a millimeter-wave band phase array radio, communication signals are transmitted and received in the 28 GHz band, and power is transmitted. 24 GHz band. This unit can be used as a repeater mounted on either side of a wall-like shield, and converts radio waves in the 24 GHz band to DC power, eliminating the need for an external power supply.

However, the receivers that have been developed so far have the problem that beam steering (a technology that compresses and transmits radio waves in any direction) is not possible for radio waves coming from a wide range, and power efficiency. Less. Newly developed radio is trying to solve this problem.

To receive a wider range of radio waves through the beam steering, we designed a new “antenna integrated face shifter”. This is to replace the two point-symmetrically installed antennas with a switch to operate as a 180 degree face shifter and to install another pair of point-symmetric antennas in pairs. This enables horizontal / vertical beam steering, enabling low-loss and wide-range radio wave transmission / reception without reducing the efficiency of the wireless power transmission.

Prototype millimeter-wave band phased array radio and wireless IC (Source: Tokyo Institute of Technology)

In addition, we have developed a “retrospective backcattering technology” that can transmit wireless communication signals in the same direction as the arrival direction of the received signal. Relayed.

The prototype of the millimeter-wave band faced array radio is equipped with a 4-chip radio IC, which integrates 16 transceivers into one chip, and is configured as a 64-element faced array radio.

As a result of the measurements and evaluations, when the beam steering received wireless power transmission from 0 to 45 degrees, we succeeded in retaining up to 46% of the power generated, which was several% worse than before. Moreover, even with the same level of electricity being generated, the transmission distance is more than double.

Since this unit is passive in transmitting and receiving communications, it is possible to configure a large-scale step-by-step array without increasing power consumption, and to determine the appropriate array size according to the functions required as a repeater each time, which is said to be flexible. Radio equipment development is possible. In the future, this technology may lead to the expansion of high-speed millimeter-wave band high-speed communication areas and the realization of unrestricted wireless terminals available for charging time.

Compare with previous research (Source: Tokyo Institute of Technology)