
Abstract — We propose a high-gain multilayer differential
integrated antenna based on antenna-in-package (AiP) solution
for 60 GHz communications. Using the conventional low-cost
printed circuit board (PCB) process, the 60 GHz phased array
antenna element and 16-element phased array antenna prototype
are fabricated. For the antenna element, measurement results
show that a gain of about 8.9 dBi and bandwidth more than 15
GHz for |S11|<-10 dB are achieved in the 60 GHz band, and the
simulated efficiency is larger than 90%. For the phased array, two
beam-fixed (0 degree and 30 degree) 16-element array antennas
achieve gains of 16.6 dBi and 13.9 dBi, respectively. Furthermore,
the measured results are in good agreement with simulations.
Index Terms—Phased array antenna, stacked patch antenna,
antenna in package, millimeter-wave, broadband, high gain, beam
scan, system on package
I. INTRODUCTION
The 60 GHz band is very attractive for high data-rate
communication applications (up to multi-Gbps) due to the
unlicensed 7 GHz spectrum. Due to the high path loss at 60GHz,
a high gain antenna is needed to maintain the link budget
requirements. Basically, the phased array antenna can achieve a
high gain and beam scanning capability with beamforming
techniques, which is good for LOS and NLOS communication
scenarios. Regarding the phased array antenna element,
end-fire antennas, such as Vivaldi and Yagi antenna, have high
gain performance [1, 2], but they usually have larger electrical
size and decrease the package compactness. Considering the
mass-market consumer electronics, the patch antenna is
preferred, with which a low-cost light-weight and compact
packaging solution can be realized.
Until now, the 60 GHz phased array modules with antenna-
in-package (AiP) using low-temperature co-fired ceramic
(LTCC) and multilayer organic printed circuit board (PCB)
process are widely studied [3, 4]. In [5], patch antennas with
artificial magnetic conductor (AMC) are proposed to improve
the radiation performance, but it requires large area to prevent
the surface wave propagation. In [6], a shorted square post wall
is employed to surround the patch antenna, suppressing the
surface wave and improving the antenna performance. But this
square post wall needs an additional via process, making the
fabrication complex and increasing the cost, in particular for
mm-wave frequency.
In these works [3, 4], to achieve the wideband performance,
the air cavity technology is used, which increase the fabrication
complexity and reduce the reliability.
In response to the large-volume low-cost and reliable
packaging requirements, in this work, based on conventional
PCB process, an AiP multilayer differential integrated phased
array antenna without air cavity is proposed. To suppress the
surface wave effect and to improve the antenna performance, a
rectangular ring is employed. In this way, compared to [3-5] the
advantages in the fabrication cost and reliability are enhanced,
and the bandwidth and gain performance are improved. The
measurements show the antenna element achieves 8.9 dBi gain
and >15GHz bandwidth for |S11|<-10 dB at 60 GHz band.
Based on this antenna element, two beam-fixed (0 degree and
30 degree) 16-element array antennas is also fabricated and
tested to verify the beam scanning performance.
II.A
NTENNA DESIGN
A. Antenna in package
Fig. 1 illustrates the cross-section of the AiP prototype,
which is realized with the traditional low-cost PCB process.
The proposed AiP solution consists of four laminates (RO3003
and TLY-5 etc) and three bondply layers. As shown in Fig.1,
the radiation elements are designed on top two metals, and the
feeding network on metal 4 are aperture coupled to the antenna.
Metal 7 is used to realize the low speed trace and the power
plane. The ground metal 3 layer, between the radiation and
feeding layers, acts as a shielding layer, and it can minimize the
influence of the feeding line, low speed trace and the power
Low-Cost High-Gain Differential Integrated
60 GHz Phased Array Antenna in PCB Process
Tao Zhang, Lianming Li
†
, Haiyang Xia, Xujun Ma Dixian Zhao, and Tie Jun Cui
†
School of Information Science and Engineering, Southeast University
†
The cross section of proposed phased array antenna packaging
,(((