Aip radar sensor module

Abstract

This invention provides a packaged antenna radar sensor module, comprising a multilayer circuit board, a high-frequency circuit unit, and an antenna unit. The multilayer circuit board consists of a top layer, a bottom layer, and an intermediate layer sandwiched between them. The high-frequency circuit unit includes a filter element and a stepped impedance matching element, located on the top layer, for filtering out the second harmonic. The filter element is disposed on the RF input path, and its length perpendicular to the signal input direction is one-quarter wavelength of the second harmonic. The filter element and the stepped impedance matching element are connected through a path with a physical dimension of half the wavelength of the second harmonic. The stepped impedance matching element includes a plurality of segments, each segment having a physical dimension of one-quarter wavelength of the second harmonic. The antenna unit on the bottom layer is coupled to the high-frequency circuit unit on the top layer via the intermediate layer.

Claims

1. A radar sensor module with an encapsulated antenna, comprising: a multilayer circuit board having a top layer, a bottom layer, and an intermediate layer, wherein the intermediate layer is sandwiched between the top layer and the bottom layer; a high-frequency circuit unit disposed on the top layer for transmitting a primary carrier wave and filtering out a second harmonic, the high-frequency circuit unit comprising: a filter element disposed on an input path of a radio frequency signal, the filter element having a circular pattern, and the length of the filter element in a direction perpendicular to the input of the radio frequency signal being a quarter wavelength of the second harmonic; and a step impedance matching element coupled to the filter element; wherein... The filter element and the step impedance matching element are connected through a path with a physical size of half the wavelength of the second harmonic; and the step impedance matching element has a plurality of segments, each of which has a physical size of a quarter wavelength of the second harmonic; and an antenna unit is disposed on the bottom layer and coupled to the high-frequency line unit of the top layer through the middle layer.

2. The radar sensor module with an encapsulated antenna as described in claim 1, wherein the circular pattern is teardrop-shaped, elliptical, or hammer-shaped.

3. The radar sensor module with an encapsulated antenna as described in claim 1, wherein the segments of the stepped impedance matching element comprise: a first segment configured close to the filter element and having a design linewidth line from high impedance to low impedance; a second segment coupled to the first segment and having a design linewidth line of high impedance; and a third segment configured away from the filter element and coupled to the second segment and having a design linewidth line of high impedance to low impedance.

4. The radar sensor module with an encapsulated antenna as described in claim 3, wherein: In the first segment, the line width closer to the filter element is smaller than the line width farther from the filter element; in the second segment, the line widths are consistent. And in the third segment, the line width coupled to the second segment is greater than the line width on the side away from the second segment.

5. The radar sensor module with an encapsulated antenna as described in claim 4, wherein the linewidth of the second segment is smaller than the linewidth of the side furthest from the filter element.

6. A radar sensor module with an encapsulated antenna as described in claim 1 or 3, wherein, A plurality of first conductive vias are disposed around the filter element, and these conductive vias are disposed on the top layer and the intermediate layer.

7. A radar sensor module with an encapsulated antenna as described in claim 1 or 3, wherein, A plurality of second conductive vias are disposed around the step impedance matching element, and these conductive vias are disposed on the top layer, the middle layer and the bottom layer.

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