LTCC-based Packaged Array Antenna Design

Antenna in Package(Ai P)based on low-temperature co-fired ceramics(LTCC)is currently one of the hotspots in the field of short-range detection.In this paper,the LTCC-based packaged antenna is researched and a packaged array antenna based on LTCC is designed.The main research contents include:(1)A microstrip antenna is designed based on the LTCC process.The size of the rectangular patch is reduced by 13% by the way of opening two pairs of symmetrical grooves on the edge of the patch;the impedance bandwidth is increased from 0.67 GHz to 6.22 GHz by setting 4 parasitic patches on the upper dielectric substrate and setting an air cavity in the upper dielectric substrate;the insertion loss is reduced and the gain of the antenna unit is increased by1 d B by metal holes connecting the upper and lower ground plates which are set at the transition position of the strip line and the metal probe.(2)With the above-mentioned microstrip antenna as the antenna unit,an array antenna based on LTCC is designed.The method of adding rectangular metal strips on the surface of the array antenna is used to suppress the surface wave,which reduces the coupling effect between the antenna elements,increases the gain of the array antenna by 1d B,and reduces the size of the side lobe.The antenna unit and array antenna are processed and tested,and the actual test results are consistent with the simulation results.(3)An encapsulation layer is set under the array antenna,and a rectangular encapsulation cavity of appropriate size is designed in the encapsulation layer by using the lamination characteristics of LTCC,by which the cavity will not produce resonance effects in the working frequency band,and avoid the influence on the chip by the cavity resonance on radio frequency.At the same time,metal through holes grounded at both ends are arranged around the rectangular package cavity to reduce the external electromagnetic interference to 0.03%.Finally,the influence of the length,width,height of the package cavity and the number of package cavities on the package antenna is studied within the range of meeting the volume limit.