PhD Dissertation:Mirmehdi Seyyedesfahlan
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Mirmehdi Seyyedesfahlan
Electronics Engineering, PhD Dissertation, 2015


Thesis Jury

Prof. Dr Ibrahim Tekin (Thesis Advisor), Assoc. Prof. Ayhan Bozkurt,

Asst. Prof. Gullu Kiziltas Sendur, Asst. Prof. Ahmet Oncu, Prof. Dr Ali Yapar



Date & Time: December 24, 2015 –  10:00 AM

Place: FENS G035

Keywords : On-chip antenna, ACP probe, 77 GHz automotive radar, W-band measurement  




In this dissertation, on-chip antennas for integration in a single RFIC radar chip and alternative wire-bonded PCB/chip package for 77 GHz automotive radar front-end are studied and manufactured.

To meet the purpose of dissertation, design and implementation of flat, L-shaped and T-shaped W-band on-chip strip dipole antennas integrated with a LC balun circuit are presented. The on-chip antennas and the balun circuit are realized by using IHP’s 0.25 µm SiGe BiCMOS technology with a localized back-side etch (LBE) module to decrease substrate loss.

It has been observed that measurements are highly influenced by the antenna placements and the ACP110-A-GSG-100 probe. Thus, a software calibration is performed similar to a network analyzer calibration to model the effect of ACP probe, and then the antenna reflection coefficient is calculated using the modeled probe-fed antenna.

Finally, a low cost 77 GHz 4-element phased-array radar receiver front-end module is designed and manufactured using PCB patch antennas to get rid of on-chip antennas surface wave and achieve better array gain. The receiver package is implemented by integrating active phase shifter chips on a single layer Rogers 3003 PCB board using ball-to-wedge bonding with insertion loss less than 7.5 dB at 77 GHz; this loss is compensated by the gain of chips’ LNA.


A novel method which exploits Klopfenstein tapering is used to connect coplanar waveguide to microstrip line at W-band frequency for chip to PCB board transition. The measured gains of the phased-array receiver and passive 4-element antenna array are compared. The receiver and passive array achieve the maximum gains of 9.7 dBi and 10.4 dBi at 77 GHz. The beam can be steered to ±30°.