Optical Carrier transmission rates

About: Optical Carrier transmission rates is a research topic. Over the lifetime, 2463 publications have been published within this topic receiving 33293 citations.

Full-duplex radio-over-fiber system with novel source-free base station using polarization multiplexing

Abstract: A cost-effective radio-over-fiber (RoF) system with novel source-free base station (BS) has been proposed and demonstrated for the first time, by employing polarization multiplexing (PolMUX). At a central station (CS), a downlink laser output is split into two orthogonal states of polarization (SOPs) and the two SOPs are used for an intermediate frequency (IF) signal and a local oscillation (LO), respectively. At a BS, we can obtain a 5 GHz IF signal for microwave access and a baseband signal for wireline access, as well as a 60 GHz LO for up/down conversions. A downlink 65 GHz wireless signal can be generated by mixing the 5 GHz IF signal with the 60 GHz LO and meanwhile an uplink baseband signal can be achieved by mixing the uplink 60 GHz signal with the 60 GHz LO which is generated at each BS. In this system, the uplink baseband signal is modulated onto the reused optical carrier while the 60 GHz LO used for up/down conversions is remotely delivered. Therefore, there are no optical or electric sources needed in each BS which could significantly reduce the system overall cost. The results successfully verify the feasibility of the proposed RoF system.

A Radio over Fiber System with Simultaneous Wireless Multi-Mode Operation Based on a Multi-Wavelength Optical Comb and Pulse-Shaped 4QAM-OFDM

Abstract: In this paper, we propose a radio over fiber transmission system with simultaneous wireless multi-mode operation based on multi-wavelength optical comb and pulse shaping. This study is an initial attempt to accomplish simultaneous wireless multi-mode operation on a single optical carrier. A multi-wavelength optical comb with 13 flat optical wavelengths and space of 10 GHz is achieved by utilizing radio frequency (RF)-optics modulation and parameter configuration. The central station contains four adjacent optical wavelengths separated from the multi-wavelength optical comb by a wavelength division multiplexer, that one is modulated by 4QAM-OFDM signals with an up-converted carrier frequency of 5 GHz. The signals modulated with a single-sideband can be obtained by employing pulse shaping. The single-sideband optical signals are combined with the other three optical wavelengths and then transmitted over a standard single-mode fiber with a length of 50 km. In this arrangement, we can obtain several wireless carriers with frequencies of 5 GHz, 25 GHz, 45 GHz, and 65 GHz by direct detection. These wireless carriers are used for wireless transmission between the RF remote units and the mobile terminals. Additionally, in the radio frequency (RF) remote unit, we have three pure optical sources that can be utilized for the uplink transmission. With single channel and direct optoelectronic modulation, the optical and wireless communication with 10 Gbps can be accomplished in the whole process of system network transmission.

Coherent optical orthogonal frequency division multiplexing (OFDM) reception using self optical carrier extraction

Abstract: A method includes producing interference between a received optical OFDM signal and an optical carrier extracted from the received optical OFDM signal to provide optical coherent detection of the received optical OFDM signal. Preferably, producing the interference includes optically splitting the received optical OFDM signal into a first part that is filtered to extract the carrier from the received optical OFDM signal and a second part similar to the received optical OFDM signal.

Packet router for use in optical transmission networks

Abstract: Packets conveying data are received by a router via input ports which impose on them optical carrier waves whose wavelengths correspond to the ports. Respective time-delays are applied to the packets and they are broadcast to spatial selectors that transmit them to spectral selectors. Amplifiers are distributed over the paths of the packets and the paths are organized in such a manner as to limit the number of semiconductor optical switches in the selectors and to minimize noise and optical crosstalk affecting the packets.

Direct detection method and system based on two-channel orthogonal pilot frequency optical signals and device

Abstract: The invention discloses a direct detection method and system based on two-channel orthogonal pilot frequency optical signals and a device, and relates to the field of optical signal modulation and direct detection The method comprises the following steps that a transmitting terminal modulates plural modulation signals to two paths of optical carriers, and two paths of optical signals are generated; the first optical carrier and the second optical carrier with 90-degree phase shift are coupled, the first optical carrier is first optical pilot frequency, and the second optical carrier with the 90-degree phase shift is second optical pilot frequency; the two paths of optical signals are coupled with the two paths of optical pilot frequency respectively, and the two-channel orthogonal pilot frequency optical signals are generated and sent; a receiving terminal carries out wavelength division demultiplexing on the received signals, two paths of received signal are obtained and are detected by two photoelectric detectors, signal restoration is carried out through a digital signal processing algorithm, and complete signal amplitude and phase information is obtained The amplitude and phase information of the transmitted signals can be detected at the same time, and the transmission distance larger than 100 kilometers is achieved