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Abstract—The efficiency of Electro-Optic Modulators (EOM) is directly related to how the rf signal is imposed onto the optical signal. Other factors affecting this efficiency are: the selected architecture and the Electro-Optic materials responsible for modulation through the Electro-Optic Effect. In this paper we demonstrate a millimeter wave antenna integrated EOM that operates at 94 GHz. To improve efficiency, the antenna is integrated directly onto the active region of the electro-optic effect based EOM. Notably, conventional antennas had to be modified to achieve a feed port that is best suited for the selected EOM architecture. For the antenna design optimization, we devised a design procedure that is more suitable for these type of devices. We proposed a design methodology that insures an optimum Field Enhancement (FE) that is responsible for modulation. A novel overall EOM architecture that promotes increased efficiency that makes use of the inherently lossy EO material only where needed in the optical link by making use of an adiabatic transition from a passive Optical waveguide to active portion of the optical link. 

On chip antennas with integrated electro-optic modulators (EOMs) are attractive for millimeter wave applications. Such EOMs are placed at the antenna feed and enable the mixing of the incoming millimeter wave (mm-wave) signal with an optical carrier. As such, the mm-wave capture is turned into an optical signal that can be easily processed for imaging using standard infrared cameras. Our proposed on-chip antenna with the EOM modulator operated at 94 GHz or 77 GHz, with the antenna tuned at that frequency. For high modulation efficiency, it is critical that the modulator region is as small as possible with the optical waveguide leading to the EOM, also being well-matched. Notably, the enhanced field at the antenna feed leads to higher modulation efficiency and sensitivity. Therefore, an optimum antenna design must hasve as large as possible field strength at the feed. 

Existing millimeter wave imaging systems have not lived up to expectations, neither in performance nor in achieving manageable size, weight, and power (SWAP). As in airports, they remain bulky, time consuming to use and not useful in preventing threats as their promise might have been. We need a small camera-like, low cost, compact, sensitive, and versatile Passive Millimeter-Wave Imaging (PMWI) enable a broader field of imaging applications. The main challenge with existing PMWI is the need for scanning causing bulkiness and time-delays for standoff applications. Similarly, secure communication at long distances is extremely important for all government and commercial applications, but the development of low power and wideband transceivers that operate across large distances is technically a very challenging task; 

There is a growing interest to implement antennain-package (AiP) systems for a variety of applications such as imaging, beamforming, integrated transceivers, and radars. Substrate integrated pyramidal antennas are valuable AiP candidates owing to their small form factor, integration ease, and high gain. However, height reduction, dielectric losses and integration of the latter can drastically degrade their gain pattern and limit their applications. This degradation is mainly due to undesired excitations on the surface of the dielectric. For the first time in this paper, we present a Grounded Co-Planar Waveguide-fed (GCPW) 94GHz low temperature cofired ceramic (LTCC) pyramidal horn antenna. To prevent parasitic TE excitations, a mushroom type High Impedance Surface (HIS) periphery is implemented. The combined antenna with HIS surrounding leads to approximately 2.3dB improvement in gain. Concurrently, the 3dB beamwidth is reduced by 26 in both E-Plane and H-Plane 

There is a strong interest to implement antennain-package (AiP) systems for a cohort of applications such as imaging, beamforming, integrated transceivers, and radars. Substrate integrated pyramidal antennas (SIPA) are valuable AiP candidates owing to their small form factor, integration ease, and high gain. However, height reduction and substrate integration can drastically reduce the overall directivity of such antennas and hence limit their potential applications. This degradation is mainly due to surface waves propagating and radiating on the dielectric. For the first time in this paper, we present a 94GHz low temperature cofired ceramic (LTCC) integrated pyramidal horn antenna. To prevent transverse magnetic (TM) surface waves, a mushroom type electromagnetic bandgap (EBG) structure is implemented in the surrounding of the horn. The LTCC fabrication is particularly suitable for this kind of structure. Since only a single well is needed to fabricate the horn and the EBG structure, complexity and cost are minimized. The combined antenna with EBG surrounding leads to approximately 1.8dB improvement in maximum directivity. Concurrently, the 3dB beamwidth is reduced by 10 for the E-Plane and 20 for the H-Plane