US 12,092,747 B2
Apparatus and method for generating GNSS signal
Jihoon Ryoo, Incheon (KR); Hoyoung Kim, Incheon (KR); Dong Gi Youn, Seoul (KR); Young-Kyung Jeong, Namyangju-si (KR); and Kyung Young Heo, Paju-si (KR)
Assigned to IDCITI.COM, Seoul (KR); and Replex. Co., LTD., Seoul (KR)
Filed by IDCITI.COM, Incheon (KR); and Replex. Co., LTD., Seoul (KR)
Filed on Oct. 7, 2021, as Appl. No. 17/450,213.
Claims priority of application No. 10-2020-0137081 (KR), filed on Oct. 21, 2020.
Prior Publication US 2022/0120917 A1, Apr. 21, 2022
Int. Cl. G01S 19/42 (2010.01)
CPC G01S 19/421 (2013.01) 12 Claims
OG exemplary drawing
 
1. An apparatus for generating a global navigation satellite system (GNSS) signal, the apparatus comprising:
a receiver configured to receive GNSS navigation information for a plurality of GNSS satellites, store the GNSS navigation information, receive a real-time satellite signal, and calculate a frequency shift value of the real-time satellite signal with respect to a default carrier frequency based on the real-time satellite signal;
at least one signal generator configured to receive the GNSS navigation information from the receiver, and generate pseudo GNSS signal information corresponding to a current time and a current location based on the GNSS navigation information and the frequency shift value; and
a transmitter configured to generate a pseudo GNSS signal based on the pseudo GNSS signal information, and amplify and output the pseudo GNSS signal,
wherein the GNSS navigation information is information indicating an estimated location of a GNSS satellite over time,
wherein the receiver is further configured to generate a local signal by applying a coarse/acquisition (C/A) code phase value of the GNSS navigation information to a carrier signal of a default carrier frequency, wherein the carrier signal of the default carrier frequency is configured to be generated by the apparatus, and calculate the frequency shift value and a coarse/acquisition (C/A) code phase difference value, by cross-correlating the real-time satellite signal with the local signal,
wherein the at least one signal generator is further configured to track a carrier frequency in which a Doppler shift is reflected and the C/A code phase value, based on the calculated frequency shift value and the calculated C/A code phase difference value, and generate the pseudo GNSS signal information by applying the tracked carrier frequency and the tracked C/A code phase value to the GNSS navigation information, and
wherein the receiver is configured to:
receive the GNSS navigation information in a first period, and
transmit the GNSS navigation information to the at least one signal generator in a third period,
wherein the at least one signal generator is configured to generate and output the pseudo GNSS signal information in a second period, and
wherein the second period is shorter than the first period, and the third period is shorter than the first period and longer than the second period.