# US 12,007,503 B2 · Method and apparatus for rear cross collision warning > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,007,503 B2 - Document ID: US12007503B2 - Status: Granted - Kind: B2 - Application number: 17/239,890 - Filed: 2021-04-26 - Published: 2021-11-25 - Granted: 2024-06-11 - Earliest claimed: 2020-05-22 - Assignees: Hyundai Mobis Co., Ltd. - Applicants: Hyundai Mobis Co., Ltd. - Inventors: Eun Seok Kang - Web page: https://patentgrep.com/patent/US12007503B2 ## CPC - G01S 7/415: {Identification of targets based on measurements of movement associated with the target} - G01S 7/414: {Discriminating targets with respect to background clutter} - G01S 13/42: Simultaneous measurement of distance and other co-ordinates (indirect measurement G01S13/46) - G01S 13/52: Discriminating between fixed and moving objects or between objects moving at different speeds - G01S 13/931: of land vehicles - G08G 1/16: Anti-collision systems (road vehicle drive control systems for predicting or avoiding probable or impending collision otherwise than by control of a particular sub-unit B60W30/08) - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - G08G: TRAFFIC CONTROL SYSTEMS (guiding railway traffic, ensuring the safety of railway traffic B61L; arrangement of road signs or traffic signals E01F9/00; radar or analogous systems, sonar systems, lidar systems specially adapted for traffic control G01S13/91, G01S15/88, G01S17/88; {radar or analogous systems, sonar systems, lidar systems specially adapted for anti-collision purposes G01S13/93, G01S15/93, G01S17/93}) ## Abstract A method with rear cross collision warning includes: dividing a surrounding area of a host vehicle into a plurality of cells arranged in lateral and longitudinal directions; creating a grid map on which cells, among the plurality of cells, corresponding to positions where a stationary object around the host vehicle is viewed are classified as occupied cells; determining a position of a reflective structure reflecting radar signals based on a positional relationship between the occupied cells on the grid map; and determining, based on the determined position of the reflective structure and either one of a position of a tracking target viewed by the radar and moving direction of the tracking target, whether the tracking target is a ghost tracking target. ## Claims ### Claim 1 A method for providing a rear cross collision warning, comprising: dividing an area around a host vehicle into a plurality of cells arranged in lateral and longitudinal directions; creating a grid map on which cells, among the plurality of cells, corresponding to positions where a stationary object around the host vehicle is viewed are classified as occupied cells; determining a position, with respect to the host vehicle, of a reflective structure reflecting radar signals based on a positional relationship between the occupied cells on the grid map; and determining, based on the determined position of the reflective structure and a moving direction and velocity of the tracking target, whether the tracking target is a ghost tracking target. ### Claim 2 (depends on 1) The method according to claim 1, wherein the creating of the grid map includes classifying cells corresponding to points where the stationary object is viewed by radar as the occupied cells. ### Claim 3 (depends on 1) The method according to claim 1, wherein the creating of the grid map includes classifying the cells corresponding to the positions where stationary object is viewed as occupied cells, in response to radar maintaining viewing rates equal to or higher than a predetermined reference viewing rate during a predetermined reference viewing cycle, or in response to a magnitude of signals received by the radar being equal to or greater than a predetermined threshold. ### Claim 4 (depends on 1) The method according to claim 1, wherein the determining of the position of the reflective structure includes determining that the occupied cells represent one reflective structure, in response to a distance between the occupied cells in a column of the grid map being within a predetermined threshold distance, and concluding that two end cells among the occupied cells determined to represent the one reflective structure are a start occupied cell and an end occupied cell, respectively, of the one reflective structure. ### Claim 5 (depends on 1) The method according to claim 1, wherein the determining of whether the tracking target is the ghost tracking target includes determining that the tracking target is the ghost tracking target, in response to the tracking target moving toward the position of the reflective structure. ### Claim 6 (depends on 1) The method according to claim 1, wherein the determining of whether the tracking target is the ghost tracking target includes determining that the tracking target is the ghost tracking target, in response to a lateral position of the tracking target being farther away from the host vehicle than a lateral position of the reflective structure is, a magnitude of a lateral positional change of the tracking target being directed in a direction toward the host vehicle, and a longitudinal position of the tracking target falling between a start point and an end point of the reflective structure. ### Claim 7 (depends on 1) The method according to claim 1, wherein the determining of whether the tracking target is the ghost tracking target includes determining that the tracking target is the ghost tracking target, in response to a lateral position of the tracking target being farther away from the host vehicle than a lateral position of the reflective structure is, a magnitude of a lateral positional change being directed in a direction toward the host vehicle, and a straight line representing a moving path of the tracking target crossing the position of the reflective structure. ### Claim 8 (depends on 1) The method according to claim 1, wherein the determining of whether the tracking target is the ghost tracking target includes determining that the tracking target is the ghost tracking target, in response to a lateral position of the tracking target falling between the position of the reflective structure and a position of the host vehicle, a lateral positional change of the tracking target being directed in a direction toward host vehicle, and a lateral acceleration of the tracking target being greater than a reference acceleration that is calculated in physical terms in a condition in which the tracking target starts moving in a stationary state from the position of the reflective structure. ### Claim 9 An apparatus with rear cross collision warning, comprising: a radar configured to view an object in a surrounding area of a host vehicle; and a controller configured to: divide a surrounding area of the host vehicle into a plurality of cells in lateral and longitudinal directions, and create a grid map on which cells, among the plurality of cells, corresponding to positions where a stationary object around the host vehicle is viewed are classified as occupied cells; determine a position of a reflective structure, with respect to the host vehicle, reflecting radar signals of the radar, based on a positional relationship between the occupied cells on the grid map; and determine, based on the determined position of the reflective structure and a moving direction and velocity of a tracking target viewed by the radar, whether the tracking target is a ghost tracking target. ### Claim 10 (depends on 9) The apparatus of according to claim 9, wherein the controller further configured to: divide the surrounding area of the host vehicle into the plurality of cells in the lateral and longitudinal directions, and create the grid map on which the cells corresponding to the position where the stationary object around the host vehicle is viewed are classified as the occupied cells; determine the position of the reflective structure reflecting the radar signals, based on the positional relationship between the occupied cells on the grid map; and determine, based on the determined position of the reflective structure and either one of the position of the tracking target and the moving direction of the tracking target, whether the tracking target is the ghost tracking target. ### Claim 11 (depends on 10) The apparatus according to claim 10, wherein the controller is further configured to classify cells corresponding to points where the stationary object is viewed by the radar as occupied cells. ### Claim 12 (depends on 10) The apparatus according to claim 10, wherein the controller is further configured to classify the cells corresponding to the positions where the stationary object is viewed as the occupied cells, in response to the radar maintaining viewing rates equal to or higher than a predetermined reference viewing rate during a predetermined viewing cycle, or in response to a magnitude of signals received by the radar being equal to or greater than a predetermined threshold. ### Claim 13 (depends on 10) The apparatus according to claim 10, wherein the controller is further configured to determine that the occupied cells represent one reflective structure, in response to a distance between the occupied cells in a column of the grid map being within a predetermined threshold distance, and conclude that two end cells among the occupied cells determined to represent the one reflective structure are a start occupied cell and an end occupied cell, respectively, of the one reflective structure. ### Claim 14 (depends on 10) The apparatus according to claim 10, wherein the controller is further configured to determine that the tracking target is the ghost tracking target, in response to the tracking target moving toward the position of the reflective structure. ### Claim 15 (depends on 10) The apparatus according to claim 10, wherein the controller is further configured to determine that the tracking target is the ghost tracking target, in response to a lateral position of the tracking target being farther away from the host vehicle than a lateral position of the reflective structure is, a magnitude of a lateral positional change of the tracking target being directed in a direction toward the host vehicle, and a longitudinal position of the tracking target falling between a start point and an end point of the position of the reflective structure. ### Claim 16 (depends on 10) The apparatus according to claim 10, wherein the controller is further configured to determine that the tracking target is a ghost tracking target, in response to a lateral position of the tracking target being farther away from the host vehicle than a lateral position of the reflective structure is, a magnitude of the lateral positional change of the tracking target being directed in a direction toward the host vehicle, and a straight line representing a moving path of the tracking target crossing the position of the reflective structure. ### Claim 17 (depends on 10) The apparatus according to claim 10, wherein the controller is further configured to determine that the tracking target is the ghost tracking target, in response to a lateral position of the tracking target falling between the position of the reflective structure and a position of the host vehicle, a lateral positional change of the tracking target being directed in a direction toward the host vehicle, and a lateral acceleration of the tacking target being greater than a reference acceleration that is calculated in physical terms in a condition in which the tracking target starts moving in a stationary state from the position of the reflective structure.