US 12,474,458 B2
Communication device, information processing method, and non-transitory computer-readable storage medium
Yoshiki Oishi, Aichi (JP); Kenichi Koga, Aichi (JP); Tatsuya Koike, Aichi (JP); Kento Kataoka, Aichi (JP); and Nobuyoshi Kikuma, Aichi (JP)
Assigned to KABUSHIKI KAISHA TOKAI RIKA DENKI SEISAKUSHO, Aichi (JP); and NAGOYA INSTITUTE OF TECHNOLOGY, Aichi (JP)
Filed by KABUSHIKI KAISHA TOKAI RIKA DENKI SEISAKUSHO, Aichi (JP); and NAGOYA INSTITUTE OF TECHNOLOGY, Aichi (JP)
Filed on Jan. 19, 2023, as Appl. No. 18/098,992.
Claims priority of application No. 2022-015472 (JP), filed on Feb. 3, 2022; and application No. 2022-163508 (JP), filed on Oct. 11, 2022.
Prior Publication US 2023/0243947 A1, Aug. 3, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G01S 11/08 (2006.01); G01S 13/76 (2006.01)
CPC G01S 11/08 (2013.01) [G01S 13/76 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A communication device comprising:
a wireless communication section configured to wirelessly receive a signal from another communication device; and
a control section configured to
correlate a first signal with a second signal at a designated interval,
the second signal being a signal associated with the first signal, and being received by the wireless communication section in a case where the other communication device transmits a signal including a pulse as the first signal,
convert a data matrix into a format including a matrix product of an expanded modal matrix and an expanded signal matrix, the data matrix being a matrix obtained by arranging one or a plurality of correlation computation results that are each a result obtained by correlating the first signal with the second signal of the wireless communication section at the designated interval, the expanded modal matrix being a matrix including a plurality of elements indicating the correlation computation results obtained on an assumption that the signal is received at respective set times, the expanded signal matrix being a matrix obtained by arranging expanded signal vectors for the one or the plurality of correlation computation results, and the expanded signal vector being a vector including a plurality of elements each indicating whether or not there is the signal of the wireless communication section at each of the set times, and an amplitude and a phase of the signal,
estimate the expanded signal matrix that minimizes a predetermined norm by iterative calculation that uses a regularization parameter that is a positive infinitesimal, and
estimate a reception time of the second signal based on the expanded signal matrix that minimizes the predetermined norm,
wherein the control section executes the iterative calculation separately at a plurality of stages, sets a value of the regularization parameter used for the iterative calculation at or after a second stage of the plurality of stages to a value of the regularization parameter or more used for the iterative calculation at a previous stage, and changes the value of the regularization parameter based on a reception status of the second signal during the iterative calculation at or after the second stage, and
wherein the control section measures a distance between the communication device and the other communication device based on the reception time of the second signal.