Phase shifting system, RF chip, and radar sensor

A radio frequency (RF) chip, comprising a phase shifting system, the phase shifting system comprising at least two cascaded transmission line phase-shifting units, wherein

• a respective transmission line phase-shifting unit of the at least two cascaded transmission line phase-shifting units is configured to receive at least one phase shifting control signal and to shift a phase of a RF signal by a first phase or a second phase according to the at least one phase shifting control signal;
• each transmission line phase-shifting unit comprises a plurality of groups of transmission lines including a first group of transmission lines and a second group of transmission lines;
• a first subset of transmission lines in the first group of transmission lines of each transmission line phase-shifting unit are physically isolated from a second subset of transmission lines in the first group of transmission lines of an adjacent transmission line phase-shifting unit to prevent current transmission between the first subset of transmission lines and the second subset of transmission lines;
• and
• transmission lines of the second group of transmission lines of each transmission line phase-shifting unit are coupled to respective transmission lines of the second group of transmission lines of an adjacent transmission line phase-shifting unit.