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Paramétrages

Paramétrages

1. US20170045609 - Method for calibrating a MIMO radar sensor for motor vehicles

Note: Texte fondé sur des processus automatiques de reconnaissance optique de caractères. Seule la version PDF a une valeur juridique

Claims

1. A method for calibrating an antenna diagram of a multiple input, multiple output (MIMO) radar sensor having N tx transmitting antenna elements and N rx receiving antenna elements, comprising:
before commissioning of the radar sensor:
storing an antenna diagram that associates with each of a plurality of several angles θ a respective control vector a(θ) that is made up of a transmitting control vector a tx(θ) and a receiving control vector a rx(θ);
after commissioning:
performing a radar measurement to localize an object;
checking whether the localized object is a single target or a multiple target;
if the localized object is a single target:
performing a single input, multiple output (SIMO) measurement with each of the transmitting antenna elements;
estimating the angle θ of the object based on the measurement results;
calculating a first comparison variable, dependent on the components of the transmitting control vector a tx(θ), for each transmitting antenna element;
calculating a second comparison variable, dependent on the results of the SIMO measurements, for each transmitting antenna element; and
correcting the transmitting control vector a tx(θ) on the basis of a known relationship between the first and second comparison variables for each transmitting antenna element.
2. The method as recited in claim 1, wherein the following relationships are used to correct the transmitting control vector a tx(θ):

           a tx,n(θ)/ a tx,1(θ)= y n(θ)/ y 1(θ)
where a tx,n(θ) are the components of the transmitting control vector a tx(θ), a tx,1(θ) is any one of those components, and the variables y n(θ) for all n=1 . . . N tx are defined by

           y i(θ)= a rx H(θ) xi
where a rx H(θ) is the vector Hermitian-conjugated with the receiving control vector a rx(θ) and xi is a vector whose components indicate complex amplitudes of signals that were transmitted by the i-th transmitting antenna element and were received by the N rx receiving antenna elements.
3. The method as recited in claim 1, wherein the following relationships are used to correct the transmitting control vector a tx(θ):

           a tx,n(θ)/ a tx,1(θ)=(1/ N rx) Σ k( x n,k /x 1,k)
where a tx,n(θ) are the components of the transmitting control vector a tx(θ), a tx,1(θ) is any one of those components, and the variables x n,k indicate complex amplitudes of signals that were transmitted by the n-th transmitting antenna element and were received by the k-th receiving antenna element.
4. A method for calibrating an antenna diagram of a multiple input, multiple output (MIMO) radar sensor having N tx transmitting antenna elements and N rx receiving antenna elements, the method comprising:
before commissioning of the radar sensor:
storing an antenna diagram that associates with each of a plurality of several angles θ a respective control vector a(θ) that is made up of a transmitting control vector a tx(θ) and a receiving control vector a rx(θ),
after commissioning:
performing a radar measurement to localize an object;
checking whether the localized object is a single target or a multiple target;
if the localized object is a single target:
performing a multiple input, single output (MISO) measurement with each of the transmitting antenna elements;
estimating the angle θ of the object based on the measurement results;
calculating a first comparison variable, dependent on the components of the receiving control vector a rx(θ), for each receiving antenna element;
calculating a second comparison variable, dependent on the results of the MISO measurements, for each receiving antenna element; and
correcting the receiving control vector a rx(θ) on the basis of a known relationship between the first and second comparison variables for each receiving antenna element.
5. The method as recited in claim 4, wherein the following relationships are used to correct the receiving control vector a rx(θ):

           a rx,n(θ)/ a rx,1(θ)= x′ n(θ)/ x′ 1(θ)
where a rx,n(θ) are the components of the receiving control vector a rx(θ), a rx,1(θ) is any one of those components, and the variables x′ n(θ) for all n=1 . . . N rx are defined by)

           x n 1(θ)=Σ i a tx,i*(θ) xi n
where a tx,i(θ) is the i-th component of the transmitting control vector a tx(θ) and xi is a vector whose components indicate complex amplitudes of signals that were transmitted by the i-th transmitting antenna element and were received by the N rx receiving antenna elements.
6. The method as recited in claim 4, wherein the following relationships are used to correct the receiving control vector a rx(θ):

           a tx,n(θ)/ a tx,1(θ)=(1/ N rxk( x n,k /x 1,k)
where a rx,n(θ) are the components of the receiving control vector a rx(θ), a rx,1(θ) is any one of those components, and the variables x k,n indicate complex amplitudes of signals that were transmitted by the k-th transmitting antenna element and were received by the n-th receiving antenna element.