M María García Larrodé

Bidirectional radio-over-fiber link employing optical frequency multiplication

We propose a bidirectional radio-over-fiber link consisting of an optical downlink transmission employing the optical frequency multiplication principle, a remote local oscillator (LO) generation, a remote down-conversion of the radio-frequency uplink signals, and an optical uplink transmission employing intensity modulation-direct detection. Experiments demonstrate the optical up-conversion of 64-level quadrature amplitude modulated radio signals to 17.8 GHz after transmission over 4.4 km of multimode fiber, 12.5 and 25 km of single-mode fiber in the downlink; the uplink performance is evaluated in terms of down-conversion loss employing the optically generated LO.

Fiber-based broadband wireless access employing optical frequency multiplication

Employing optical frequency multiplication, we demonstrate experimentally the simultaneous delivery of different 64QAM radio signals at 5.8 and 17.7 GHz after 4.4 km of multimode fiber in a single radio-over-fiber link. We also propose a flexible mechanism for the dynamic radio link adaptation, and the simultaneous transmission of an in-band control channel with the wireless data channels for power control purposes at the antenna site is demonstrated experimentally

Microwave Signal Generation and Transmission Based on Optical Frequency Multiplication With a Polarization Interferometer

A novel scheme is proposed and experimentally demonstrated for the generation of microwaves, based on the optical frequency multiplication principle employing a polarization interferometer. Generation of 120-Mb/s 64-quadrature-amplitude-modulation microwave signals at 40 and 24 GHz and its transmission over 25 km of single-mode fiber and 4.4 km of multimode fiber, respectively, are successfully demonstrated. The scheme is robust against laser phase noise, presents tolerance against dispersion impairments in transmission, and shows high-performance stability.

All-Fiber Full-Duplex Multimode Wavelength-Division-Multiplexing Network for Radio-Over-Multimode-Fiber Distribution of Broadband Wireless Services

We present a full-duplex multimode wavelength-division-multiplexing ring network for the distribution of broadband wireless services. It successfully combines the use of all-fiber wavelength selecting multimode add/drop multiplexing nodes with a radio-over-multimode-fiber technique that is robust against modal dispersion impairments in multimode fiber links, and allows a reliable delivery of wireless services beyond 5 GHz. The multimode add/drop multiplexing nodes are built with commercially available narrowband multimode fiber Bragg gratings. The feasibility of the proposal is experimentally investigated with the distribution of 120-Mb/s 64 quadrature amplitude modulation radio signals at 24 GHz over a 4.4-km-long multimode fiber ring with multimode add/drop multiplexing nodes, achieving error vector magnitude values below 4.5%.

Theoretical and Experimental Demonstration of OFM Robustness Against Modal Dispersion Impairments in Radio Over Multimode Fiber Links

A theoretical signal analysis is presented to demonstrate the robustness of optical frequency multiplication (OFM) against modal dispersion impairments in radio-over-multimode fiber links. The predicted system robustness is also experimentally demonstrated with the generation and transmission of 60 Mb/s and 120 Mb/s 64-QAM radio-frequency signals at 24 GHz over three different 4.4-km-long multimode fiber links with different modal group delays and frequency response characteristics, yielding error vector magnitude values below 4% and 4.8% (for 60 and 120 Mb/s, respectively).

Transmission of Microwave Signals beyond the Modal Bandwidth of Multimode Fiber Links

Employing the optical frequency multiplication method, we present an experimental performance analysis of the generation of microwave carriers up to 40 GHz and their transmission over a 4.4 km multimode fiber link. Also, 16 QAM and 64 QAM radio signals up to 20MS/s symbol rate are recovered successfully in the 24-30 GHz band after 4.4 km multimode fiber transmission, complying with the transmitter constellation error requirements of wireless standard IEEE 802.11a

Layer 2 and 3 Contention Resolution and Radio-Over-Fiber in OCDMA PON for Transparent Optical Access in Personal Networks

In this paper, we analyze, for the first time, the eminent role of optical transparent networking in personal networks. We show how an optical access network mitigates many issues with respect to connectivity and mobility management. A concrete personal network user-scenario deduces requirements for such an architecture. A combination of passive optical network, optical code-division multiple access (OCDMA), and radio-over-fiber exhibits minimal cost and complexity because of centralized network control and management, resource sharing, and simplified network nodes. We enable transparent peer-to-peer communication between optical networking units in the OCDMA passive optical network subnet of the central office. We use, for the first time, simultaneously optical code-sense medium access control and optical code packet switching for contention resolution.

WDM OFM-based radio-over-fiber distribution antenna system employing GCSR tunable lasers

We demonstrate experimentally the feasibility of a wavelength-multiplexed radio-over-fiber distribution antenna system in a star-tree configuration based on optical frequency multiplication and employing GCSR tunable lasers for the generation of the swept light source.

All-optical processing of time-serial IM/DPSK encoded label and payload packets

We demonstrate an all-optical label and payload processor based on nonlinear optical signal processing with semiconductor optical amplifiers. The processor separates the label and the payload, and generates a synchronization pulse, used to control the label comparison operation in an all-optical routing node

FSK-WDM to IM-OTDM conversion for fiber-to-the-premises access networks

We experimentally demonstrate a FSK-WDM to IM-OTDM conversion system, based on a MZI wavelength converter. The FSK channels data rate is 500 Mbps, while error and power penalty free conversion to 5 Gbps IM-OTDM is reported. Operation at 10 Gbps is also shown.