Theoretical and experimental optimum system design for LTE-RoF over varying transmission span and identification of system nonlinear limit

W. P. Ng, T. Kanesan, Z. Ghassemlooy, Chao Lu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

34 Citations (Scopus)


This paper proposes an optimum radio-over-fiber (RoF) system design to extend the coverage of the third-generation partnership program (3GPP) long-term evolution (LTE) base station, i.e., eNodeB. The system is theoretically and experimentally demonstrated as the high-speed interface between eNodeB and a relay node. The LTE signals under test comprise three different modulation schemes, namely, quaternary phase-shift keying (QPSK), 16-quadratic-amplitude modulation (QAM), and 64-QAM, which are modulated onto orthogonal frequency-division multiplexing (OFDM) at 2.6 GHz. The RoF system design is based on the distributed feedback (DFB) laser direct modulation and direct detection receiver. The spurious-free dynamic range (SFDR) considering the third-order intermodulation analysis of the DFB laser achieved 1.93-dB dynamic range gain to improve the modulation efficiency. The practical investigation reveals three distinctive optical power transmission regions, namely, linear, intermixing, and nonlinear regions. The QPSK, 16-QAM, and 64-QAM systems in the intermixing region achieved error vector magnitudes (EVMs) of ∼1.144%, ∼1.2%, and ∼ 1.21%, respectively, for 10-km transmission, whereas at 60 km, the achieved EVMs are ∼5.86%, ∼ 5.96%, and ∼6.01%, respectively. The intermixing region for the 10-60-km transmission span achieved the most optimized EVM and within the 3GPP LTE limit of 8%. Additionally, we also demonstrate that nonlinear distortion proportionally increases with linear distortion as the transmission span increases.
Original languageEnglish
Article number6268287
Pages (from-to)1560-1571
Number of pages12
JournalIEEE Photonics Journal
Issue number5
Publication statusPublished - 29 Aug 2012


  • Long-term evolution (LTE)
  • optical orthogonal frequency-division multiplexing (OOFDM)
  • radio-over-fiber (RoF)

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Electrical and Electronic Engineering

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