Error Vector Magnitude Evaluation of Terahertz Transmitter Employing Optical Frequency Comb

Shigeru KUWANO  Daisuke IIDA  Jun TERADA  Akihiro OTAKA  Naoto YOSHIMOTO  Shintaro HISATAKE  Tadao NAGATSUMA  

IEICE TRANSACTIONS on Electronics   Vol.E98-C   No.8   pp.799-807
Publication Date: 2015/08/01
Online ISSN: 1745-1353
DOI: 10.1587/transele.E98.C.799
Type of Manuscript: Special Section PAPER (Special Section on Microwave Photonics)
Category: MWP Subsystem
terahertz transmission,  optical frequency comb,  error vector magnitude,  

Full Text: PDF>>
Buy this Article

Terahertz (THz) band is an attractive candidate for future broadband (> 10 Gb/s) wireless backhaul and fronthaul. THz transmitter employing optical frequency comb can provide high quality THz carrier, and is useful to the future broadband THz communication systems based on coherent transmission technique. To realize coherent transmission, high quality carrier generation is essential and it is important to evaluate the signal quality of a THz transmitter. In this paper, we derive error vector magnitude (EVM) including optical impairments (optical amplifier noise, laser phase noise, optical crosstalk and IQ imbalance of optical modulator) of the optical frequency comb based transmitter. The calculated EVM is in good agreement with simulated one, and practical requirements for optical impairment are indicated. The analysis will be useful in the design of THz transmission systems employing an optical frequency comb.