WO-2026094221-A1 - RIS AND MOBILE BODY COMMUNICATION SYSTEM

Abstract

The present invention realizes a multi-functional RIS. An RIS (20) comprises a first backscatter communication element (21) that performs backscatter communication with a self-driving vehicle (50) that is at a first position (P1) on a road surface positioned in the vicinity of an installation position. The first backscatter communication element performs on-off keying with respect to incident radio waves (41) from a base station (10), thereby notifying the self-driving vehicle at the first position of first self-driving assistance information.

Inventors

• KAWAI, YUTO

Assignees

• ソフトバンク株式会社

Dates

Publication Date

20260507

Application Date

20241031

Claims (6)

1. A Reconfigurable Intelligent Surface (RIS) that extends cell coverage in a mobile communications network, A downlink communication element in the aforementioned cell that reflects radio waves for downlink communication from the base station to the terminal, It includes a first backscatter communication element that performs backscatter communication with an autonomous vehicle located at a first position on the road surface near the installation location of the RIS, The first backscatter communication element performs on/off keying in response to radio waves incident from the base station, thereby broadcasting first automated driving support information to the automated driving vehicle located at the first position.
2. The RIS according to claim 1, wherein the first backscatter communication element adds a header to the signal of the first automated driving support information to distinguish it from the signal of the downlink communication, and broadcasts the first automated driving support information to the automated driving vehicle located at the first position.
3. The first backscatter communication element is a plurality of elements, The RIS according to claim 1 or 2, wherein the plurality of first backscatter communication elements perform the same on/off keying to each other.
4. The first backscatter communication element is a plurality of elements, The RIS according to any one of claims 1 to 3, wherein the plurality of first backscatter communication elements are arranged so as not to be adjacent to one another.
5. The system further includes a second backscatter communication element that performs backscatter communication with an autonomous vehicle located at a second position different from the first position on the road surface near the installation position of the RIS, The RIS according to any one of claims 1 to 4, wherein the second backscatter communication element performs on/off keying in response to radio waves incident from the base station to broadcast second autonomous driving support information to the autonomous vehicle located at the second position.
6. A mobile communication system comprising the RIS described in any one of claims 1 to 5.

Description

RIS and mobile communication systems This invention relates to a RIS (Rapid Infrared System) and a mobile communication system including the RIS. The mobile communication network to which this invention applies utilizes a so-called RIC (RAN Intelligent Controller) to optimize and automate the wireless resources of the RAN (Radio Access Network). In such a mobile communication network, the deployment of a device called a RIS (Reconfigurable Intelligent Surface) is being considered for the purpose of improving high-frequency band coverage and wireless communication quality. Regarding RIS (Radio-Sensing Indicator), in addition to improving high-frequency band coverage and wireless communication quality, other functions are also being considered. For example, Patent Document 1 discloses the use of RIS as an example of a power transmission device that wirelessly supplies power to terminal equipment. This figure illustrates a schematic of a mobile communication system including RIS according to Embodiment 1.This figure illustrates a schematic of a mobile communication system including RIS according to Embodiment 2. [Embodiment 1] Figure 1 is a diagram illustrating the schematic of a mobile communication system 100 according to Embodiment 1. The mobile communication system 100 provides a mobile communication network to a terminal 30 capable of wireless communication. The terminal 30 is, for example, a portable information terminal such as a smartphone or tablet. As shown in Figure 1, the mobile communication system 100 includes a base station 10 and a RIS (Reconfigurable Intelligent Surface) 20. For simplicity, Figure 1 shows only one base station 10, one RIS 20, and one terminal 30. However, the mobile communication system 100 may have multiple base stations 10 and multiple RIS 20s. Furthermore, the mobile communication system 100 may provide a mobile communication network to multiple terminals 30. Base station 10 constitutes a cell in the mobile communication network. Specifically, base station 10 emits radio waves 41. Radio waves 41 are the radio waves used for downlink communication from base station 10 to terminal 30. The range in which terminal 30 can receive radio waves 41 constitutes the coverage of the cell formed by base station 10. RIS20 extends cell coverage in mobile communication networks. RIS20 comprises multiple downlink communication elements 25 that reflect radio waves 41. Each downlink communication element 25 is a reflective element whose direction of reflection of the radio waves 41 can be arbitrarily controlled. Multiple downlink communication elements 25 can scatter the radio waves 41 in various directions, for example. Furthermore, multiple downlink communication elements 25 can concentrate the radio waves 41 at a specific location as needed. The downlink communication element 25 reflects the radio waves 41 emitted from the base station 10 to areas where the radio waves 41 cannot directly reach, such as areas located in the shadow of a building relative to the base station 10. As a result, the terminal 30 can receive the radio waves 41 reflected by the downlink communication element 25, even in areas where the radio waves 41 emitted from the base station 10 cannot directly reach, as shown in Figure 1. In other words, the coverage of the cell formed by the base station 10 is extended by the RIS 20 to areas where the radio waves 41 emitted from the base station 10 cannot directly reach. Furthermore, the RIS 20 may perform spatial division multiplexing transmission using multiple downlink communication elements 25. This can improve the speed of downlink communication from the base station 10 to the terminal 30. The RIS 20 further comprises a first backscatter communication element 21. The first backscatter communication element 21 performs backscatter communication with the autonomous vehicle 50. The autonomous vehicle 50 is a vehicle equipped with autonomous driving capabilities, located at a first position P1 on the road surface near the installation location of the RIS 20. The first backscatter communication element 21 is a reflective element capable of switching between a state in which it reflects radio waves 41 toward the first position P1 and a state in which it does not reflect them. By switching between the state in which it reflects and the state in which it does not reflect the radio waves 41, the first backscatter communication element 21 generates radio waves 55 containing a signal indicating the first automated driving support information and transmits it to the automated driving vehicle 50. That is, the first backscatter communication element 21 notifies the automated driving support information to the automated driving vehicle 50 by performing on/off keying in response to the radio waves 41 incident from the base station 10. The first automated driving support information is information related to the automated driving of the automated driving vehicle 50 at the first position P