New MMICbased Millimeterwave Power Source ChauChing Chiong, PingChen Huang, YuhJing Huang, MingTang

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New MMIC-based Millimeter-wave Power Source
Chau-Ching Chiong, Ping-Chen Huang, Yuh-Jing
Huang, Ming-Tang Chen (ASIAA), Shou-Hsien Weng,
Ho-Yeh Chang (NCUEE), Che-Chiang Kuo, Huei Wang
(NTUEE)
Overview Voltage-controlled oscillator (VCO) and
PLL components are designed and fabricated using
2um InGaP/GaAs HBT and 0.15 um mHEMT. New
MMIC-based millimeter-wave power sources working
at Ka- and W-band are under development. We
expect MMIC system with its cheap,
light-weightiness, easily-controlled and low
power-consumption will be ideal choice for future
large antenna arrays applications, e. g. SMA,
SKA, and ALMA.

• Wide bandwidth MMIC VCO at Ka-band

LO-PLL system
Based on the experience from the first HBT run in
the year 2006, where Ku- and K-band VCOs were
fabricated, differential Ka-band VCOs are
designed in the year 2007.
A new millimeter-wave LO-PLL system with MMIC VCO
as central core is proposed. With different
combination of frequency multiplication factor,
N, and frequency division factor, M, the system
can be used as Ka- or W-band power source (Fig.
7). The final goal of our new configuration is to
have a power source in miniature SOC (system on
chip) or SIP (system in package) format.
Fig. 1. Schematic of the differential,
double-tuned VCO.
Fig. 2. Chip photo of VCO A, with chip size of 2
x 1mm2.
The measured output frequency and output power of
the VCO A versus the tuning voltage (Vtu) are
shown in Fig. 3 and 4.
Fig. 7. Block diagram of proposed
MMIC-based millimeter-wave power source.
In order to achieve this, mixer, power amplifier
and frequency divider are already designed in
house and fabricated using mHEMT and HBT
technologies. Fig. 8 shows the chip photos of
them. Mixer for Ka-band system was fabricated by
mHEMT process. Conversion gain of -10 to -20 dB
was measured with LO of 23 to 29 GHz and RF of 27
to 33 GHz (Fig. 9). Frequency divider was
fabricated using HBT. It operates up to 15 GHz
with -20 dBm output power, or operates at lower
frequency with higher output power (Fig. 11). The
HBT Darlington power amplifier has very wide 3 dB
bandwidth from 2 to 30 GHz (Fig. 10). These parts
will be packaged and assembled this year.
Frequency multiplier will be designed this year.
Fig. 3. Measured and simulated output oscillating
frequency and power at GSG pad of VCO A versus
the tuning voltage, Vtu.
Fig. 4. Measured output spectrum of VCO A with
Vtu 0 V. Measured phase noise at 1-MHz offset
is -101.7 dBc/Hz.
Fig. 5 and 6 show comparison of the fabricated
VCOs with reported wideband VCOs (tuning range gt
10). Our VCOs are compatible with other in term
of oscillation bandwidth and phase noise. A
detail comparison with other two Ka-band wideband
VCOs can be found in Table I. Our dc power
consumption of VCO is only 1/2 to 1/3 of those of
the other ones.
Fig. 8. Chip photos of mixer (left, 1.5 x 1 mm2),
frequency divider (middle, 1.5 x 1 mm2), and
power amplifier (right, 1 x 1 mm2).
VCO 2007
VCO 2007
VCO 2006
VCO 2006
Fig. 6. Phase noise at 1 MHz offset from the
carrier of the reported wideband VCOs.
Fig. 5. Oscillation bandwidth of the reported
wideband VCOs.
Fig. 9. Conversion gain of mHEMT mixer.
Fig. 10. Small signal gain of Darlington PA.
Table I. Comparisons of Previously Reported
Ka-Band VCOs and This Work.
Fig. 11. Measured results of frequency divider.
Input frequency and sensitivity (left), and
output power at various bias condition (right).
Reference 1 H. Li and H. M. Rein, IEEE Journal
of Solid-State Circuits, vol. 38, no. 2, pp.
184-191, Feb. 2003.
2 L. Zhang, R. Pullela, C. Winczewski, J. Chow,
D. Mensa, S. Jaganathan, and R. Yu, IEEE Radio
Frequency Integrated Circuits (RFIC) Symposium,
pp. 85-88, 2002.