US 11,940,524 B2
Radar apparatus and radar method
Takaaki Kishigami, Tokyo (JP); Ryosuke Shiozaki, Tokyo (JP); Hidekuni Yomo, Kanagawa (JP); and Kenta Iwasa, Tokyo (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Filed by PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Filed on Sep. 26, 2022, as Appl. No. 17/952,824.
Application 17/952,824 is a continuation of application No. 16/584,341, filed on Sep. 26, 2019, granted, now 11,486,994.
Claims priority of application No. 2018-185243 (JP), filed on Sep. 28, 2018; application No. 2018-185294 (JP), filed on Sep. 28, 2018; and application No. 2019-061414 (JP), filed on Mar. 27, 2019.
Prior Publication US 2023/0008565 A1, Jan. 12, 2023
Int. Cl. G01S 13/34 (2006.01); G01S 7/40 (2006.01); G01S 13/02 (2006.01)
CPC G01S 13/343 (2013.01) [G01S 7/4026 (2013.01); G01S 7/403 (2021.05); G01S 7/4034 (2021.05); G01S 2013/0245 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A radar device, comprising:
a radar transmission circuit that transmits one or more transmission signals, each of the one or more transmission signals having a transmission period Tr, and
a radar receiving circuit that receives one or more reflected signals in which the one or more transmission signals are reflected by an object and estimates a direction of the object based on the one or more reflected signals,
wherein the radar transmission circuit includes:
Nt transmission antennas, where Nt is an integer greater than or equal to 2; and
a control circuit that sets a transmission gap period between a first period and a second period,
wherein the transmission gap period is a period during which the one or more transmission signals are not transmitted,
wherein one of the Nt transmission antennas transmits a transmission signal for each transmission period Tr,
wherein each of the Nt transmit antennas transmits a transmission signal at least once in a period Np,
wherein the first period is equal to an integral multiple of the period Np,
wherein the second period is set after the first period and is equal to an integral multiple of the period Np,
wherein the radar receiving circuit includes:
a receiving antenna that receives the one or more reflected signals;
a Doppler analysis circuit that analyzes a Doppler frequency component of each of the one or more reflected signals in the first period and the second period;
a detection circuit that detects a first peak Doppler frequency component in the first period and a second peak Doppler frequency component in the second period, the first peak Doppler frequency component being detected from a first period Doppler frequency component whose received power is greater than a threshold value in the first period, the second peak Doppler frequency component being detected from a second period Doppler frequency component whose received power is greater than the threshold value in the second period;
a determination circuit that compares the first peak Doppler frequency component in the first period with the second peak Doppler frequency component in the second period to determine whether or not the first peak Doppler frequency component in the first period and the second peak Doppler frequency component in the second period includes an aliasing signal; and
a direction estimation circuit that estimates the direction of the object based on the Doppler frequency component of each of the one or more reflected signals in the first period and the second period to which a presence or an absence of the aliasing signal is applied,
when the period Np is larger than Nt times the transmission period Tr:
the control circuit selects, within the period Np, a first transmitting antenna among the Nt transmission antennas multiple times, selects each second transmitting antenna other than the first transmitting antenna once among the Nt transmission antennas, and sets a period in which the first transmitting antenna is selected to be shorter than a period in which each second transmitting antenna part is selected; and
the detection circuit detects one of the first peak Doppler frequency component in the first period or the second peak Doppler frequency component in the second period, the first peak Doppler frequency component and the second peak Doppler frequency component corresponding to a transmission signal from the first transmitting antenna, and
the determination circuit determines whether the aliasing signal is included in the one of the first peak Doppler frequency component or the second peak Doppler frequency component.