IEEE Photonics Journal (Jan 2024)
Silicon Photonics for Inter/Intra-Chip Wireless Communication Using RF On-Chip Antennas
Abstract
This study experimentally demonstrates both inter-chip and intra-chip RF transmission for short-range microwave communication using on-chip antennas, implemented on a silicon photonic platform. The unification of antenna with photonic integrated circuits (PICs) reduces system loss for high data rate communication by eliminating parasitics. We designed, fabricated, and measured two antenna topologies (blade and triangular) for intra-chip communication and one (meander antenna) for both inter-chip as well as intra-chip communication. The three on-chip antenna topologies have resonance at 15.7 GHz, 13.2 GHz, and 12.6 GHz, and maximum transmission coefficient (S21) value above −30 dB for all antennas. Their operation is further validated by low return loss value (S11 ≤ −20 dB), indicating strong impedance matching with minimal power reflection. The intra-chip RF data transmission has been confirmed with bit- error-rate (BER) measurements of below 10−9 up to a data rate of 4 Gbps. We have also performed inter-chip communication between two on-chip antennas separated by a distance of upto 18 mm and accomplished 4 Gbps transmission with BER < 10−9. Our findings indicate that on-chip antennas integrated onto silicon photonic chips provides a seamless conversion between electrical and optical signals. This integration enables various on-chip RF wireless applications such as chip-to-chip and off-chip communication, along with wireless sensing off-chip. Furthermore, the incorporation of an integrated antenna facilitates the realization of integrated RF photodetector-antenna emitters on a silicon photonic chip, thereby significantly reducing size, weight, area, and power requirements.
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