Coherent Radio-Over-Fiber and Millimeter-Wave Radio Seamless Transmission System for Resilient Access Networks

Abstract

We propose a millimeter-wave (MMW) coherent radio-over-fiber (RoF) transmission system for application to an access network with a direct broadband last-mile wireless connection to an optical fiber network. The coherent RoF system comprises an optical twotone RoF signal generator with an advanced modulation format for high-throughput transmission and employs a digital-signal-processing-aided coherent detection technique for MMW radio, which is a technique similar to that of optical digital coherent detection. As proof of concept, a 20-GBd quadrature phase-shift keying RoF transmission over 20 km of optical fiber before a radio transmission over 20 m of air is demonstrated. The results of the radio transmissions using Cassegrain-type antenna pairs with a gain of 50 dBi are consistent with theoretical estimations; this suggests the possibility of developing a midrange transmission system using a high-power MMW amplifier.

Performance Analysis of Digital Modulation for Coherent Detection of OFDM Scheme on Radio over Fiber System

“…So for the fiber length of 100 km, 16-QAM has constellation better when compared to other modulation formats with the increase in the value of BER and SER is small anyway. Based on all results, It also shows that this OFDM-RoF scheme with coherent detection is better than previous research [10], [11], where the bit rate can be achieved on 10 Gbps 16 QAM with the small BER and SER values for long transmission up to 100 km SMF.…”

“…There are also many types of research on the coherent detector system on the radio over fiber, in particular, the use of the local oscillator optical down-conversion receiver. Including the use of millimeterwave (MMW) on coherent radio-over-fiber (RoF) has been able to be applied to an optical and radio seamless network conversion, the results show 20 Gbaud QPSK has a data rate of 37.2 Gbps, and the transmission distance can be extended up to two km under the operation of 10-Gbaud when a high power amplifier with higher output power of 20 dBm is used [10]. Judging from the effects of chromatic dispersion, radio systems for optical fiber modulated in phase with coherent detection can be an alternative for RF signal transmission to optical fiber for the use of frequency of 100 GHz, the value of the QPSK BER of 10-4 can be achieved with the level of under 16 dB SNR with a maximum value is obtained at 1-Gbps on fiber length of 80 km.…”

“…The purpose of this paper is to analyze the performance of coherent detection of OFDM-RoF system for digital modulation variation at 10 Gbps up to 100 km fiber length. Based on the previous research, the coherent detection of OFDM-RoF system uses a QAM/PSK sequence with two optical modulator and single continuous wave laser (CW-Laser) as optical input at the transmitter like in research [10], and four balanced PIN detector with phase shifter 900 and a local oscillator at receiver as well as the configuration of coherent detection on previous research [11]. OptiSystem 13 and OptiFiber 2 software are used for simulation.…”

A full‐duplex dual‐polarization QPSK in a digital radio‐over‐fiber system

“…7,8 Even though various IM-DD schemes have been considered to provide a better performance of IM/DD systems, 9,10 optical coherent RoF links have been proposed for the transport of high-speed wireless signals and to achieve better performance than IM-DD links. 11,12 Additionally, coherent detection enabled dramatic capacity improvements of RoF systems, owing that to the spatial multiplexing gain through multi-input and multi-output (MIMO) technologies and polarization multiplexing which offers the seamless conversion of 2 × 2 MIMO transmissions in the fiber section and the wireless section. 4 Since coherent RoF systems have been implemented based on DSP algorithms which are well known from high capacity baseband systems, one of the main challenges in RoF systems is generation and distribution of mm-wave RoF signals.…”

Optical FM-CW signal generation for millimeter-wave imaging and OFDR applications

“…The obtained optical spectrum shown in Fig. 1(b) indicated that the system for optical FM-CW signal generation was successfully configured as an optical frequency quadrupler [4,5]. An optical coupler (C1) split the signal into two: one for MMW signal generation and the other for OFDR.…”