Summary
International Symposium on Antennas and Propagation
2009
Session Number:3D1
Session:
Number:3D1-2
Fabrication Tolerance Analysis of a 60GHz Stacked Circular Patch Antenna Based on LTCC technology
Woojin Byun, B.-S Kim, K.-S Kim, M.-S Kang, M.-Sun Song,
pp.987-990
Publication Date:2009/10/21
Online ISSN:2188-5079
Summary:
Recently a lot of applications in the millimeter (mm) wave band such as point-to-point communications at 70 to 80GHz, car radar at 77GHz and image sensor at 94GHz, are in service. Furthermore since the FCC has assigned 57~64GHz of unlicensed frequency for wireless applications, there have been standard organization activities such as IEEE 802.15.3c and 802.11 VHT for mm-wave short-range applications with a goal to transmit a few Gbps multimedia data[1]. There have been widespread trend toward higher levels of integration to reduce cost, size and complexity. Low temperature co-fired ceramic (LTCC) technology is one of several candidates for mm-wave system in a packaging solution. It can be operated over 60GHz (low dielectric loss) and has flexibility in realizing module with easy-to-integrate circuit components like via-holes and cavity-buried components. Therefore one may expect mm-wave based products shall be commercialized within a few years with the advances of process technologies and low cost integration circuit design technologies such as Si CMOS and LTCC packaging. In general, high gain antennas such as a switched beam-forming or phased array antenna due to the relatively high free space path loss at mm-wave band [2] should be used in order to secure communication distance for WPAN applications and widen beam coverage. However, these kinds of antennas are very expensive and difficult to implement. On the contrary if the communication distance is more limited within 1~2m, an omni-directional antenna will also become one of the candidates for the WPAN application like several Gbps data transfer in between PC and an external hard disk [3] due to its extremely low cost. Previously we proposed a TM01 mode excited stacked circular patch antenna using LTCC substrates [4]. The antenna was fed by a microstrip transmission line through a signal via and showed the radiation pattern similar to that of a monopole type antenna. Simulated and measured results were shown, but working mechanism of the proposed structure is not shown and explained. In addition there were some mismatches in between those results due to LTCC manufacturing tolerances. In this paper, working mechanism of the proposed antenna is explained with simulation results and mode field patterns are shown. And the effects of various geometrical parameters are investigated in order to determine the critical factors in designing and manufacturing of a signal viafed stacked circular patch antenna using LTCC substrates. This design is applied to Ferro A6 LTCC substrate and manufactured at RN2 Tech Inc., Korea. Typical properties of LTCC substrate are the relative permittivity of 5.9, a loss tangent of 0.002 at 60GHz and one layer thickness of 100μm. Experiment results are compared with the simulated results after manufacturing tolerances are investigated and analyzed.