US 11,988,737 B2
FMCW radar sensor including synchronized high frequency components
Jo Pletinckx, Sersheim (DE); and Robert Korn, Karlsruhe (DE)
Assigned to ROBERT BOSCH GMBH, Stuttgart (DE)
Filed by Robert Bosch GmbH, Stuttgart (DE)
Filed on Aug. 24, 2020, as Appl. No. 17/000,893.
Claims priority of application No. 102019213621.4 (DE), filed on Sep. 9, 2019; and application No. 102019215191.4 (DE), filed on Oct. 2, 2019.
Prior Publication US 2021/0072352 A1, Mar. 11, 2021
Int. Cl. G01S 13/00 (2006.01); G01S 7/40 (2006.01); G01S 13/34 (2006.01); G01S 13/931 (2020.01)
CPC G01S 13/006 (2013.01) [G01S 7/4056 (2013.01); G01S 13/34 (2013.01); G01S 13/931 (2013.01)] 17 Claims
OG exemplary drawing
 
10. A radar sensor for a motor vehicle, comprising:
a signal processing unit to encode and store digital data in the radar sensor of the vehicle, which include a plurality of real values, wherein the signal processing unit is configured to perform the following:
storing at least one real value r is in an exponential representation in which r=m* b−f(k), where m* is a digital mantissa and f is a function of k that is selected from multiple functions, where the digital mantissa has a length p, b is a base, and k is a positive number that is encoded as a digital number having a length q;
wherein the exponential representation with b>2 is used for providing compressed storage of the at least one real value r, and wherein a complex number is represented by its magnitude and its phase, and the exponential representation is used for the magnitude, so that a memory requirement is reduced, or for a given memory space, an object location accuracy is improved based on a statistical analysis of the digital data and/or a quantization error is reduced,
wherein the signal processing unit includes an input stage which accepts digital data from an analog/digital converter, wherein the digital data are compressed in a compression stage and the compressed data are stored in compressed form in a memory of the radar sensor, and the compressed data are later decompressed in a decompression stage and further processed in a processing stage, and
wherein by using a larger integer base of b>2, it is provided that for a length of a digital mantissa and of the exponent k a higher resolution is achieved for a portion of the real values to be stored, so that for a particular resolution, the length of the digital mantissa and/or of the exponent k is reduced to save memory space in the radar sensor of the vehicle,
wherein the radar sensor includes a frequency modulated continuous wave (FMCW) radar having a transceiver and a plurality of antenna elements forming a planar group antenna,
wherein the radar sensor is installed in the vehicle so that the antenna elements are adjacently situated at a same height, so that a particular angular resolution capability of the radar sensor, an azimuth, is achieved,
wherein the multiple functions from which the function f is selected are stored in advance in a form of value tables,
wherein the selection of the function f and of an associated value table is based on which set of powers best fits an expected or a previously found structure of the digital data to be stored, and
wherein the signal processing unit includes multiple interlinked processing stages, including multiple FFT stages for a multi-dimensional Fourier transform.