Fabrication of a 77 GHz Rotman Lens on a High Resistivity Silicon Wafer Using Lift-Off Process

Abstract

Fabrication of a high resistivity silicon based microstrip Rotman lens using a lift-off process has been presented. The lens features 3 beam ports, 5 array ports, 16 dummy ports, and beam steering angles of ±10 degrees. The lens was fabricated on a 200 μm thick high resistivity silicon wafer and has a footprint area of 19.7 mm × 15.6 mm. The lens was tested as an integral part of a 77 GHz radar where a tunable X band source along with an 8 times multiplier was used as the RF source and the resulting millimeter wave signal centered at 77 GHz was radiated through a lens-antenna combination. A horn antenna with a downconverter harmonic mixer was used to receive the radiated signal and display the received signal in an Advantest R3271A spectrum analyzer. The superimposed transmit and receive signal in the spectrum analyzer showed the proper radar operation confirming the Rotman lens design.

Design and Performance Analysis of Millimetre-Wave Rotman Lens-Based Array Beamforming Networks for Large-Scale Antenna Subsystems

“…3 shows the characteristics of the dummy ports as an integral part of the lens, over the frequency range of operation, which are terminated with 50-Ω matched loads. The sidewall contours along with the dummy ports are efficiently designed and implemented to minimise the multiple reflections and standing waves from the sidewalls, which consequently results in the improved performance, in terms of the device efficiency [40,44]. Fig.…”

Modified CMRC LPF Using Novel Fractal Patches

“…Recently, the increasing need for high data rate and compactness in addition to the increasing congestion in the traditional spectrum are pushing the most of modern communication systems to be developed in high SHF, EHF, Ka, Q, U and V bands for many applications such as 5G communication system [1], 28 GHz RFID [2,3], hyperspectral microwave radiometer [4], synthetic aperture radar [5], inter-satellite communications [6], Wireless Gigabit Alliance(WiGig) [7], W-band imaging radiometer system [8], and the millimeter-wave satellite communications [9][10][11], radar systems [12,13]; therefore, low pass filters with an extra ultrawide stopband bandwidth are in demand to prevent inter-modulation with the new systems operating bands.…”

Design of multi-beam antenna based on Rotman lens

“…The design of Rotman lens is based mainly on waveguide, equivalent transmission line and microstrip line technologies, [12][13][14] in which the waveguide form of the Rotman lens applied in the radar system has reduced insertion loss. 9,15,16,18 The microstrip Rotman lens antenna [18][19][20][21][22] has attracted considerable attention due to its many advantages, such as low profile, light weight, small volume, simple structure, low cost, relatively stable performance in the wideband.…”