Method for calibrating an antenna diagram of an MIMO radar sensor having N tx transmission antenna elements and N rx reception antenna elements, having the steps of: prior to startup of the radar sensor: - storing an antenna diagram that assigns to each of multiple angles θ a respective control vector a (θ) that is made up of a transmission control vector a tx (θ) and a reception control vector a rx (θ), following startup: - performing a radar measurement to locate an object, - checking whether the located object is a single target or a multiple target, - if it is a single target: - performing an SIMO measurement with each of the transmission antenna elements, characterized by the following further steps: - estimating the angle θ of the object on the basis of the measurement results, - computing a first comparison variable for each transmission antenna element, which comparison variable is dependent on the components of the transmission control vector a tx (θ), - computing a second comparison variable for each transmission antenna element, which comparison variable is dependent on the results of the SIMO measurements, and - correcting the transmission control vector a tx (θ) on the basis of a known relationship between the first and second comparison variables for each transmission antenna element. prior to startup of the radar sensor: - storing an antenna diagram that assigns to each of multiple angles θ a respective control vector a (θ) that is made up of a transmission control vector a tx (θ) and a reception control vector a rx (θ), following startup: - performing a radar measurement to locate an object, - checking whether the located object is a single target or a multiple target, - if it is a single target: - performing an SIMO measurement with each of the transmission antenna elements, characterized by the following further steps: - estimating the angle θ of the object on the basis of the measurement results, - computing a first comparison variable for each transmission antenna element, which comparison variable is dependent on the components of the transmission control vector a tx (θ), - computing a second comparison variable for each transmission antenna element, which comparison variable is dependent on the results of the SIMO measurements, and - correcting the transmission control vector a tx (θ) on the basis of a known relationship between the first and second comparison variables for each transmission antenna element. - storing an antenna diagram that assigns to each of multiple angles θ a respective control vector a (θ) that is made up of a transmission control vector a tx (θ) and a reception control vector a rx (θ), - performing a radar measurement to locate an object, - checking whether the located object is a single target or a multiple target, - if it is a single target: - performing an SIMO measurement with each of the transmission antenna elements, - estimating the angle θ of the object on the basis of the measurement results, - computing a first comparison variable for each transmission antenna element, which comparison variable is dependent on the components of the transmission control vector a tx (θ), - computing a second comparison variable for each transmission antenna element, which comparison variable is dependent on the results of the SIMO measurements, and - correcting the transmission control vector a tx (θ) on the basis of a known relationship between the first and second comparison variables for each transmission antenna element.