60-GHz Transmission Link Using Uni-Traveling Carrier Photodiodes at the Transmitter and the Receiver

Ahmad Wasfi Mohammad,Cyril C Renaud,Haymen Shams,Michele Natrella,Chin-Pang Liu,Alwyn J Seeds,Chris Graham

doi:10.1109/jlt.2018.2849938

Ahmad Wasfi Mohammad, Cyril C Renaud + Show 5 more

Open Access

https://doi.org/10.1109/jlt.2018.2849938

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Abstract

We present the first demonstration of a wireless transmission link based on uni-traveling carrier photodiodes (UTC-PDs) as transmitter and receiver. In this demonstration, a UTC-PD was used at the transmitter to generate a 1-Gbps on–off keying data signal at a carrier frequency of 61.3 GHz by heterodyning two modulated optical tones originating from an optical frequency comb system. The generated electrical heterodyne signal was transmitted, using a 25-dBi gain parabolic antenna. An identical antenna was used to detect the signal at the receiver, followed by an optically pumped UTC-PD mixer to down-convert the received RF signal to an intermediate frequency of 6.3 GHz, which was subsequently amplified and acquired by a real-time oscilloscope for offline processing. The recovered data showed an open eye diagram, and a bit error rate of the order of 10–5 was measured. The receiver UTC-PD was characterized in terms of its conversion loss and noise figure (NF), and the overall NF of the receiver was measured at 21.5 dB.

Highlights

T HE Global mobile data traffic is expected to reach 49 Exabyte per month by 2021, which is a 7-fold increase compared to 2016 [1]
While the transmitter uni-traveling carrier photodiodes (UTC-PDs) was driven by coherent optical tones from a frequency comb system, the receiver UTC-PD was driven by two free running lasers, featuring a simple and widely tunable receiver
The current configuration of the receiver is partly limited by the power divider which introduces losses in the RF and the intermediate frequency (IF) paths, and limits the operating frequency of the receiver to 65 GHz

Summary

INTRODUCTION

T HE Global mobile data traffic is expected to reach 49 Exabyte per month by 2021, which is a 7-fold increase compared to 2016 [1]. Several photonic techniques for MMW generation have been demonstrated, including [12], [13]: photomixing (optical heterodyning) with two laser diodes, optical frequency combs (OFC), direct intensity modulation, optical external modulation, mode locked laser diodes (MLLD), nonlinear effects in waveguides and fibers, and Brillouin fiber lasers These methods use a photodiode for the optical to electrical conversion, by which it generates an electrical signal at a frequency that is defined by the spacing between the optical tones, as mathematically explained in [9]. We realized a 61.3 GHz wireless transmission link implementing a UTC-PD at the transmitter for MMW signal generation, by heterodyning two modulated optical tones originating from an OFC system. The conversion loss and noise figure (NF) performance of the receiver UTC-PD mixer are presented This experiment demonstrates the capabilities of the UTC-PD as an emitter and a detector of MMWs, which is an important step towards realizing photonic integrated transmitters and receivers.

UTC-PD CHARACTERIZATION

Transmitter Setup

Receiver Setup

Findings

CONCLUSION