US 12,261,352 B2
GNSS antenna system for receiving multi-band GNSS signals
Fabio Diem, Zürich (CH); Garance Bruneau, Zürich (CH); Pascal Gohl, Winterthur (CH); Tuomo Haarakangas, Oulu (FI); and Ilkka Heikura, Oulunsalo (FI)
Assigned to HEXAGON GEOSYSTEMS SERVICES AG, Heerbrugg (CH); and LEICA GEOSYSTEMS AG, Heerbrugg (CH)
Filed by HEXAGON GEOSYSTEMS SERVICES AG, Heerbrugg (CH); and LEICA GEOSYSTEMS AG, Heerbrugg (CH)
Filed on Sep. 2, 2022, as Appl. No. 17/902,547.
Claims priority of application No. 21194841 (EP), filed on Sep. 3, 2021.
Prior Publication US 2023/0072603 A1, Mar. 9, 2023
Int. Cl. H01Q 1/27 (2006.01); H01Q 1/24 (2006.01); H01Q 9/04 (2006.01)
CPC H01Q 1/27 (2013.01) [H01Q 1/246 (2013.01); H01Q 9/0414 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A GNSS antenna system for receiving GNSS signals, comprising:
at least one inverted F-antenna configured to receive GNSS signals in the L1 frequency band (L1-antenna), and
at least one inverted F-antenna configured to receive GNSS signals in the L2/L5 frequency band (L2/L5-antenna),
wherein each inverted F-antenna comprises an antenna having an antenna end point and a grounded end, a ground plane and a feed, wherein the feed is connected at an intermediate point to the antenna and wherein the antenna is connected at the grounded end to the ground plane, each inverted F-antenna having a direction defined between the grounded end and the antenna end point,
wherein the GNSS antenna system comprises four L1-antennas and four L2/L5-antennas, wherein:
a first L1-antenna of the four L1-antennas is oriented in a first direction,
a second L1-antenna of the four L1-antennas is oriented in a second direction substantially orthogonal to the first direction,
a third L1-antenna of the four L1-antennas is oriented in a third direction substantially orthogonal to the second direction and substantially antiparallel to the first direction, and
a fourth antenna of the four L1-antennas is oriented in a fourth direction substantially orthogonal to the third direction and substantially antiparallel to the second direction,
wherein each L2/L5-antenna of the four L2/L5-antennas has a corresponding L1-antenna and wherein the direction of each L2/L5-antenna substantially corresponds to the direction of the corresponding L1-antenna,
wherein each antenna of the four L1-antennas has an average distance to its respective ground plane, the average distance in particular being between the intermediate point and the ground plane or being an actual average in distance between antenna and ground plane along the antenna, and wherein the respective ground plane is in particular embodied as the common ground plane, wherein the average distance of at least one of the four L1-antennas differs from the average distance of the remaining L1-antennas, and in that at least one of the four L1-antennas is:
tuned, in particular by adjusting a distance between the intermediate point and the grounded end of the at least one tuned L1-antenna and/or by adjusting the length of the antenna of the tuned L1-antenna, and/or
phased in addition to the phase provided to the tuned L1-antenna by the first quadrifilar 4-phased antenna feeder, wherein the additional phasing is in particular provided by a delay line,
wherein tuning and additional phasing is done in such a way as to compensate influences on radiation properties of the GNSS antenna system in the L1 frequency band due to the at least one bent L1-antenna and due to the difference in average distance between at least one of the four L1-antennas and the remaining L1-antennas.