US-12625253-B2 - Multistatic radar system using wireless communication devices

US12625253B2US 12625253 B2US12625253 B2US 12625253B2US-12625253-B2

Abstract

A node in a wireless communication system coordinates multistatic radar measurements, wherein the node controls a plurality of wireless communication devices. Coordination involves obtaining an indication that a first sensing area located within a geographic area that is served by the node is to be sensed by a first radar signal. A first multistatic radar group of wireless communication devices selected from a participating group of the plurality of wireless communication devices and the node is formed, wherein the first multistatic radar group comprises at least one device for transmitting the first radar signal and at least two devices for receiving one or more reflections of the transmitted first radar signal. The first multistatic radar group is controlled to introduce the first radar signal into the first sensing area and to receive the one or more reflections of the introduced first radar signal. The sensed reflections obtained by wireless communication devices in the first multistatic radar group are caused to be combined to obtain geographical information about the first sensing area. Other aspects involve a wireless communication device interacting with a network node to receive allocated time and radio frequency resources to be used for a radar function.

Inventors

Henrik Sjöland
Fredrik Dahlgren
Ashkan Kalantari
Magnus Olsson
Gang Zou

Assignees

TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

Dates

Publication Date: 20260512
Application Date: 20200710

Claims (20)

1 . A method, performed by a network node in a wireless communication system, of coordinating multistatic radar measurements, the network node controlling a plurality of wireless communication devices, the method comprising: obtaining, from a wireless communication device, a request for radar functionality, the request representing an indication that a first sensing area located within a geographic area that is served by the network node is to be sensed by a first radar signal, the network node corresponding to a base station; forming a first multistatic radar group of wireless communication devices selected from a participating group of the plurality of wireless communication devices and the network node, the first multistatic radar group comprising at least one wireless communication device for transmitting the first radar signal and at least two wireless communication devices for receiving one or more reflections of the transmitted first radar signal, the participating group including wireless communication devices with radar functionality; controlling, based on the radar functionality, the first multistatic radar group to transmit the first radar signal into the first sensing area and to receive the one or more reflections of the introduced first radar signal; and causing sensed reflections obtained by wireless communication devices in the first multistatic radar group to be combined to obtain geographical information about the first sensing area.
2 . The method of claim 1 , wherein forming the first multistatic radar group of wireless communication devices comprises making device selections based on whether a wireless communication device under consideration is capable of performing one or more radar functions.
3 . The method of claim 1 , wherein forming the first multistatic radar group of wireless communication devices comprises making device selections based on whether a wireless communication device under consideration is being used for other communications.
4 . The method of claim 1 , wherein forming the first multistatic radar group of wireless communication devices comprises making device selections based on whether a wireless communication device under consideration is located in the first sensing area.
5 . The method of claim 1 , wherein forming the first multistatic radar group of wireless communication devices comprises making device selections based on whether a wireless communication device under consideration has a line-of-sight channel between the wireless communication device under consideration and one or more other wireless communication devices.
6 . The method of claim 1 , wherein forming the first multistatic radar group of wireless communication devices comprises making device selections based on whether a wireless communication device under consideration has communicated to the network node an indication of availability to perform one or more radar functions.
7 . The method of claim 1 , wherein forming the first multistatic radar group of wireless communication devices comprises making device selections based on whether transmission of the first radar signal by a wireless communication device under consideration will disturb one or more other communication activities being carried out by one or more of the plurality of wireless communication devices.
8 . The method of claim 1 , comprising: obtaining information that a member of the first multistatic radar group has changed position, and in response deciding whether to remove the member from the first multistatic radar group based on one or more consequences of the changed position of the member of the first multistatic radar group.
9 . The method of claim 8 , further comprising assessing whether the first multistatic radar group can continue to perform radar sensing of the first sensing area without participation of the member of the first multistatic radar group that has changed position.
10 . The method of claim 1 , comprising: obtaining an indication that a second sensing area located within the geographic area that is served by the network node is to be sensed by a second radar signal; and forming a second multistatic radar group of wireless communication devices selected from the participating group of the plurality of wireless communication devices and the network node, wherein the second multistatic radar group comprises at least one device for transmitting the second radar signal and at least two devices for receiving one or more reflections of the transmitted second radar signal.
11 . The method of claim 1 , wherein causing sensed reflections obtained by wireless communication devices in the first multistatic radar group to be combined to obtain geographical information about the first sensing area comprises: collecting sensed radar information from members of the first multistatic radar group and supplying the collected sensed radar information to one or more of the wireless communication devices.
12 . The method of claim 1 , wherein the indication that the first sensing area located within the geographic area that is served by the network node is to be sensed by the first radar signal is a request for radar functionality that is received from a requesting one of the wireless communication devices.
13 . The method of claim 12 , wherein the first multistatic radar group is one of a group of one or more existing multistatic radar groups, and wherein the method further comprises: receiving a second request for radar functionality from a second requesting one of the wireless communication devices; and determining whether the second requesting one of the wireless communication devices is suitable for inclusion in one of the one or more existing multistatic radar groups, and if so then adding the second requesting one of the wireless communication devices to the one of the one or more existing multistatic radar groups.
14 . The method of claim 13 , comprising: if the second requesting one of the wireless communication devices is not suitable for inclusion in one of the one or more existing multistatic radar groups, then determining whether a new multistatic radar group can be formed to perform the second requested radar functionality and if so, then forming the new multistatic radar group.
15 . The method of claim 13 , comprising: if the second requesting one of the wireless communication devices is not suitable for inclusion in one of the one or more existing multistatic radar groups and a new multistatic radar group cannot be formed to perform the second requested radar functionality, then adding the second requesting one of the wireless communication devices to a waiting list for future radar functionality servicing.
16 . The method of claim 1 , comprising: receiving a request from one of the plurality of wireless communication devices to withdraw from the first multistatic radar group, and in response thereto: removing the requesting one of the plurality of wireless communication devices from the first multistatic radar group; and assessing whether the first multistatic radar group can continue to perform radar sensing of the first sensing area without participation of the one of the wireless communication devices that requested withdrawal from the multistatic radar group.
17 . A non-transitory computer readable storage medium comprising instructions that, when executed by at least one processor, causes the at least one processor to carry out a method of a network node in a wireless communication system, of coordinating multistatic radar measurements, wherein the network node controls a plurality of wireless communication devices, the method comprising: obtaining, from a wireless communication device, a request for radar functionality, the request representing an indication that a first sensing area located within a geographic area that is served by the network node is to be sensed by a first radar signal, the network node corresponding to a base station; forming a first multistatic radar group of wireless communication devices selected from a participating group of the plurality of wireless communication devices and the network node, wherein the first multistatic radar group comprises at least one wireless communication device for transmitting the first radar signal and at least two wireless communication devices for receiving one or more reflections of the transmitted first radar signal, the participating group including wireless communication devices with radar functionality; controlling, based on the radar functionality, the first multistatic radar group to transmit the first radar signal into the first sensing area and to receive the one or more reflections of the introduced first radar signal; and causing sensed reflections obtained by wireless communication devices in the first multistatic radar group to be combined to obtain geographical information about the first sensing area.
18 . A network node in a wireless communication system configured to coordinate multistatic radar measurements, the network node configured to control a plurality of wireless communication devices, the network node comprising: circuitry configured to obtain, from a wireless communication device, a request for radar functionality, the request representing an indication that a first sensing area located within a geographic area that is served by the network node is to be sensed by a first radar signal, the network node corresponding to a base station; circuitry configured to form a first multistatic radar group of wireless communication devices selected from a participating group of the plurality of wireless communication devices and the network node, wherein the first multistatic radar group comprises at least one wireless communication device for transmitting the first radar signal and at least two wireless communication devices for receiving one or more reflections of the transmitted first radar signal, the participating group including wireless communication devices with radar functionality; circuitry configured to control, based on the radar functionality, the first multistatic radar group to transmit the first radar signal into the first sensing area and to receive the one or more reflections of the introduced first radar signal; and circuitry configured to cause sensed reflections obtained by wireless communication devices in the first multistatic radar group to be combined to obtain geographical information about the first sensing area.
19 . The network node of claim 18 , wherein the circuitry configured to form the first multistatic radar group of wireless communication devices comprises circuitry configured to make device selections based on whether a wireless communication device under consideration is capable of performing one or more radar functions.
20 . The network node of claim 18 , wherein the circuitry configured to form the first multistatic radar group of wireless communication devices comprises circuitry configured to make device selections based on whether a wireless communication device under consideration is being used for other communications.

Description

BACKGROUND The present invention relates to multistatic radar systems, more particularly to multistatic radar systems using wireless communication devices, and still more particularly to control of wireless communication devices for use as a multistatic radar system. There is a growing need for applications that run in mobile phones and other types of modem-equipped devices to be aware of objects and events in their surroundings as well as their position. Different sensor options for enabling this awareness include radar and cameras. There is no need to exclude one option in favor of another because information from different sensors can be combined in a process called “sensor fusion” to create a more complete picture. As used herein, the term “radar” refers to a type of sensing in which one or more radiofrequency signals are transmitted (by one or more transmitters) into a sensing environment, and reflections of those signals received (by one or more receivers). An analysis of the received reflection signals provides information about objects that the signals reflected off of in the sensing environment. Conventional technology has considered providing a mechanism for making mobile communication devices radar-capable. For example, both US Patent Application No. US 20170329449A1 (B. Silverstein and Eden Sherry, “Systems, Methods, and Devices for Utilizing Radar-Based Touch Interfaces”, November 2017) and U.S. Pat. No. 8,004,454B2 (M. Lindoff and M. Blomkvist, “Mobile Electronic Device Equipped With Radar”, August 2011) describe equipping such devices with a dedicated radar chip so that they can detect objects in the vicinity. But while most mobile phones have a camera, radar sensors are still not widely implemented. One rare exception is the Google Pixel 4 phone, which incorporates a dedicated radar chip to achieve the desired functionality. The current solution for equipping communication devices with radar capability has only a short range application that requires only low resolution (e.g., gesture recognition and detecting objects in proximity of the device). In addition, the current solutions requiring dedicated radar chips inside the mobile device lead to increased cost and the need provide additional space in the device. As another solution, U.S. Pat. No. 9,945,934 B2 (D. Corcos and D. Elad, “Radar Integration With Handheld Electronic Devices”, April 2018) describes mounting a phased array on the device to add a frequency modulated continuous wave (FMCW) radar. Such a solution is proposed for vehicle communication. However, integrating long range and high-resolution radar chips inside the mobile phones or mounting a radar enabling mounting case on the device can increase the cost and size of a mobile device substantially. The reason is that the size of an antenna array must be many wavelengths to create a narrow beam for high angular resolution. There is therefore a need for radar-enabling technology that addresses the above and/or related problems. SUMMARY It should be emphasized that the terms “comprises” and “comprising”, when used in this specification, are taken to specify the presence of stated features, integers, steps or components; but the use of these terms does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. Moreover, reference letters may be provided in some instances (e.g., in the claims and summary) to facilitate identification of various steps and/or elements. However, the use of reference letters is not intended to impute or suggest that the so-referenced steps and/or elements are to be performed or operated in any particular order. In accordance with one aspect of the present invention, the foregoing and other objects are achieved in technology (e.g., methods, apparatuses, nontransitory computer readable storage media, program means) in which a node in a wireless communication system coordinates multistatic radar measurements, wherein the node controls a plurality of wireless communication devices. Coordination by the node comprises the node obtaining an indication that a first sensing area located within a geographic area that is served by the node is to be sensed by a first radar signal. The node forms a first multistatic radar group of wireless communication devices selected from a participating group of the plurality of wireless communication devices and the node, wherein the first multistatic radar group comprises at least one device for transmitting the first radar signal and at least two devices for receiving one or more reflections of the transmitted first radar signal. The node then controls the first multistatic radar group to introduce the first radar signal into the first sensing area and to receive the one or more reflections of the introduced first radar signal; and causes sensed reflections obtained by wireless communication devices in the first multistatic radar group to be combined to obtain geographi