Idelfonso Tafur Monroy

Idelfonso Tafur Monroy
Technical University of Denmark | DTU · Department of Photonics Engineering

PhD

About

724
Publications
48,725
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6,277
Citations

Publications

Publications (724)
Article
Fifth-generation mobile networks (5G) is the established solution to satisfy the highly demanding key performance indicators such as traffic volumes, bit-rate, latency, and power consumption, among others of the future telecommunication infrastructure. The already saturated sub-6 GHz spectral band does not accommodate such requirements and forces t...
Article
Full-text available
In this paper we report the implementation and experimental evaluation of a proposed hybrid communication ecosystem for CCAM applications such as cooperative adaptive cruise control (CACC) and smart intersections. Three wireless technologies have been suggested for communications between vehicles and intelligent traffic lights and are evaluated in...
Conference Paper
The biggest barrier for many scientific and commercial applications in communications, spectroscopy, life sciences, food safety, biomedicine as well as industrial metrology is the lack of appropriate sources and detectors of THz radiation with enough power and sensitivity with small footprints and portability. Currently available photonic based THz...
Article
Full-text available
Despite the progress in the development of automated vehicles in the last decade, reaching the level of reliability required at large-scale deployment at an economical price and combined with safety requirements is still a long road ahead. In certain use cases, such as automated shuttles and taxis, where there is no longer even a steering wheel and...
Chapter
Fifth generation (5G) is the emerging mobile communications platform that aims to meet the market requirements in terms of enhanced broadband connectivity based on harnessing small cell and mmWave technology. These two in synergy will provide high capacity gain not only through the hyperdense deployment of small cell but also through accessing larg...
Article
Three convergent processes are likely to shape the future of the internet beyond-5G: The convergence of optical and millimeter wave radio networks to boost mobile internet capacity, the convergence of machine learning solutions and communication technologies, and the convergence of virtualized and programmable network management mechanisms towards...
Conference Paper
Full-text available
In this work we present, analyze, and demonstrate an efficient bidirectional ARoF system for K-band 5G fronthaul based on multicore fiber. As the 5G standard establishes, the experimental testbed is configured regarding the time division duplex scheduling and tested by transmitting OFDM signals. Furthermore, the configuration of the setup enables t...
Article
Full-text available
This article presents the experimental demonstration of synchronization of two integrated semiconductor distributed Bragg reflector lasers, fabricated with a generic multiproject wafer platform, by means of injection locking. Substantial linewidth reduction and frequency stabilization of the lasers were shown during locking of the lasers to an opti...
Article
We evaluate the impact of Power-over-Fiber (PoF) technology on the fronthaul of a 5G-NR network with an Analog-Radio-over-Fiber at 25.5 GHz on a 10 km long multicore fiber. The study in this Letter analyzes the bit error rate (BER) performance for different levels of energy transmitted by the PoF system. 133 mW of maximum optical power at reception...
Preprint
Full-text available
In this paper, an experimental analysis of the phase noise in an OFDM ARoF setup at 25 GHzfor beyond 5G is presented. The configuration of the setup allows to gradually scale the final phase noise level of the system. Moreover, an OFDM phase noise mitigation method with low complexity and delay is proposed and explained. The proposed method is an a...
Article
Full-text available
In this work we have demonstrated a waveguide integrated uni-traveling carrier photodiode on an InP-membrane on-silicon platform with 3 dB bandwidth beyond 110 GHz. With design optimization and an improved process, devices as small as 3x2m<sup>2</sup> are successfully realized. An electrical equivalent circuit model based on measured S-parameters r...
Conference Paper
Full-text available
This work studies and experimentally evaluates the performance enhancement by using PS-OFDM in a 5G mm-Wave ARoF system at 25 GHz for all 5G numerologies and with different phase noise levels.
Conference Paper
Full-text available
We experimentally analyze the ARoF based on OPLL mm-Wave generation performance for 5G fronthaul. Remarkable performance improvements are achieved for all 5G NR numerologies and different OPLL configurations despite their inherently high phase noise level.
Article
This paper presents a beyond 5G fronthaul network with dynamic beamforming and -steering. The proposed fronthaul solution deploys optical beamforming (OBF) by combining space division multiplexing (SDM), analogue radio-over-fiber (ARoF), and the novel optical beam forming network (OBFN) technologies. From the service management and orchestration (M...
Article
Full-text available
The sixth generation (6G) mobile systems will create new markets, services, and industries making possible a plethora of new opportunities and solutions. Commercially successful rollouts will involve scaling enabling technologies, such as cloud radio access networks, virtualization, and artificial intelligence. This paper addresses the principal te...
Article
A combined non-orthogonal multiple access (NOMA) and multiband carrierless amplitude and phase modulation (multiCAP) scheme is proposed for flexible resource provisioning in coherent passive optical networks (PONs). While the proposed combination increases the data-rate and the number of users through the inclusion of NOMA and multiCAP, the coheren...
Article
Full-text available
The generation and transmission of millimeter-wave signals for 5G applications require the use of broadband and high output power photodetectors to bridge from the optical and electronic domains. Therefore, the deep knowledge on the equivalent circuit characteristics of these devices is vital. This study reviews and analyzes de-embedding techniques...
Article
This article presents the experimental demonstration of a fully photonics-based heterodyne subterahertz (sub-THz) system for wireless communications. A p-i-n photodiode is used as a broadband transmitter to upconvert the signal to the sub-THz domain and a photoconductive antenna downconverts the received wave to an intermediate frequency around 3.7...
Article
Full-text available
This article presents an experimental demonstration of a high-capacity millimeter-wave 5G NR signal transmission with analog radio-over-fiber (ARoF) fronthaul over multi-core fiber and full real-time processing. The demonstration validates the core of the blueSPACE fronthaul architecture which combines ARoF fronthaul with space division multiplexin...
Article
Full-text available
Fifth-generation mobile networks (5G) are the solution for the demanding mobile traffic requirements, providing technologies that fulfill the requisites of different type of services. The utilization of the millimeter-wave (mm-wave) band is the straightforward technique to achieve high bit rates. Moreover, analog radio-over-fiber (ARoF) brings outs...
Article
The impact of bending and twisting on the impulse response matrix is investigated using optical vector network analysis. The heterogeneous 36-core 3-mode fiber under test is spooled at bending radii of 8 cm to 50 cm and additionally up to 4 twists per meter along the longitudinal direction are applied. The by-design large differential mode group de...
Conference Paper
We experimentally demonstrate a heterodyne communication link using a p-i-n photodiode and a photoconductor coupled to THz antennas without bandwidth-limiting electronic components. As a proof-of-concept, a 100 Mbit/s BPSK stream is successfully transmitted at three different channels, spaced by 40 GHz, down-converting the wireless carrier to an in...
Preprint
We demonstrate up to 12 km, 56 Gb/s DMT transmission using high-speed VCSELs in the 1.5 um wavelength range for future 400Gb/s intra-data center connects, enabled by vestigial sideband filtering of the transmit signal.
Preprint
We review some currently discussed solutions for 400 Gbit/s inter-data center WDM transmission for up to 100 km. We focus on direct detected solutions, namely PAM4 and DMT, and present two WDM systems based on these formats.
Preprint
Full-text available
We review three solutions for low-cost data center interconnects with a target reach of up to 80 km. Directly detected DMT, PAM-4 and multi-band CAP are promising modulation schemes, enabling 400 Gbit/s by combining eight channels of 56 Gbit/s.
Conference Paper
Full-text available
Fifth-generation (5G) mobile networks consist of a range of novel technologies to fulfill different and exigent requirements and serve a wide range of services. To reach this, analog radio over fiber (ARoF) fronthaul with millimeter-wave (mm-wave) cells is a firm candidate to be part of the 5G architecture. Nonetheless, combined mm-wave and ARoF sy...
Poster
A new flexible, secure FSO-CDMA system supporting end-to-end network resource slicing is proposed and investigated. New mathematical formalisms considering distinct turbulence conditions are derived. The system supports different applications, use cases, and traffic requirements.
Conference Paper
Full-text available
In this paper, an experimental analysis of the phase noise in an OFDM ARoF setup at 25 GHz for beyond 5G is presented. The configuration of the setup allows to gradually scale the final phase noise level of the system. Moreover, an OFDM phase noise mitigation method with low complexity and delay is proposed and explained. The proposed method is an...
Chapter
This work describes the advancements that next generation mobile networks can bring to emergency services on the basis of a fully 5G enabled medical emergency response scenario. An ambulance service combining autonomous driving, advanced on-board patient monitoring, remote diagnosis and remote control from the hospital is introduced, allowing incre...
Article
Full-text available
5G mobile networks aim to support a large variety of services with different and demanding requirements. To achieve this, analog radio over fiber (ARoF) fronthaul along with millimeter-wave (mmWave) cells is a strong candidate to be part of the 5G architecture. Very high throughput can be achieved by using mmWave signals due to the large available...
Article
Full-text available
The blueSPACE project focuses on the study of innovative technologies to overcome the limitations of current fronthaul networks. The key technology proposed is space-division multiplexing, which makes it possible to increase the capacity available in conventional single-mode fibers, effectively encompassing this capacity to the forecasted bandwidth...
Conference Paper
The fifth-generation (5G) of mobile systems is considered a key enabler technology for autonomous driving vehicles. This is due to its ultra-low latency, high-capacity, and network reliability. In this paper, a full end-to-end 5G automotive platform for benchmarking, certificating, and validating distinct use cases in cooperative intelligent transp...
Article
Precise characterization of space division multiplexing fibers is a key requirement for their further development and deployment in the field. Optical vector network analysis allows to measure all linear parameters of such fibers in a single, fast acquisition over a large bandwidth. As the reference arm of the optical vector network analyzer must a...
Conference Paper
Full-text available
This article reports on a W-Band (75–110 GHz) Schottky diode based balanced envelope detector in microstrip technology, featuring a transition from WR-10 to microstrip. The manufactured detector provides 20 GHz of input RF bandwidth within the W-band. A video bandwidth between 4 GHz and 6 GHz is achieved for input RF frequencies between 75 GHz and...
Conference Paper
Non-Orthogonal Multiple Access (NOMA) technique and Carrierless Amplitude Phase (CAP) modulation have been used to demonstrate pay-as-you-grow coherent Passive Optical Networks (PON) and providing a 10 Gbps aggregate data rate.
Conference Paper
A bidirectional analogue radio-over-fiber link relying on photonic heterodyning and time-division duplex is experimentally demonstrated, successfully transmitting 5G OFDM signals with data rates of 2.4 Gbit/s and 1.2 Gbit/s in down- and uplink directions over 4 m of wireless distance. An optical frequency comb laser is used together with a demultip...
Conference Paper
Full-text available
This article reports on a W-Band (75-110 GHz) Schottky diode based balanced envelope detector in microstrip technology, featuring a transition from WR-10 to microstrip. The manufactured detector provides 20 GHz of input RF bandwidth within the W-band. A video bandwidth between 4GHz and 6GHz is achieved for input RF frequencies between 75 GHz and 88...
Article
This manuscript introduces a 5G radio access network architecture concept based on ultra-dense wavelength division multiplexing (UDWDM) and incorporating an optical fronthaul network that uses a novel wireless antenna system for radio frequency transmission and reception. A ring topology is proposed where optical signals travel within the 5G UDWDM...
Article
This paper presents the system integration and packaging of a photodetector at W-band (75-110 GHz) for terahertz (THz) communications. The ErAs:In(Al)GaAs photoconductor and its feeding network based on semi-insulating indium phosphide (InP) substrate are introduced. The design of the bias-tee at W-band is described and the effect of parasitic mode...
Conference Paper
We demonstrate a heterodyne wireless system using only ErAs:In(Al)GaAs photoconductors driven by two independent telecom laser signals. The maximum Intermediate Frequency (IF) was 2.3 GHz, only limited by the bandwidth of the post-detection electronics. The maximum signal-to-carrier ratio achieved was 42.6 dB.
Conference Paper
The widespread acceptance and deployment of quantum key distribution (QKD) for data encryption requires a better understanding of the technology concerning device-to-system interfacing and network performance from current vendors. Despite the existence of a few QKD testbeds worldwide, they are neither open-access nor capable of validating component...
Conference Paper
The increasing demands for high capacity and ultra-low latency services require to introduce a 5G mobile communications infrastructure based on a centralized radio access network with space division multiplexed optical fronthaul using radio-over-fiber. The transmission of carrier aggregated 5G OFDM signals over an analog radio-over-fiber fronthaul...
Conference Paper
In this paper we analyze the perspective of digitized radio over fiber (DRoF) fronthaul, showing how to meet the requirements to cope with the future radio access networks (RANs). This entails the introduction of space division multiplexing (SDM) while increasing the flexibility and capacity of the DRoF transceivers.Since the evolution of the DRoF...
Conference Paper
This paper presents the novel SDN/NFV 5G fronthaul network scenarios deployed in the blueSPACE project. blueSPACE envisions the upgrade of the fronthaul network to include optical SDM transmission for further increasing the network capacity. One of the novelties is the introduction of ARoF transceivers to reduce the 5G fronthaul bandwidth requireme...
Conference Paper
Full-text available
The fifth generation (5G) mobile systems can be considered the way to ubiquitous Internet, pervasive computing paradigm, and a revolution in industries like automotive, media and entertainment, and eHealth. New 5G fronthaul systems based on centralized radio access networks will eventually use technology enablers such as reconfigurable optical add-...
Article
Full-text available
In this paper, we propose a model for the effect of misalignment of antennas due to mechanical vibrations and experimentally validate its accuracy in a Ka-band (26-40 GHz) transmission link. Our approach provides a valuable tool that is analytically tractable and physically simple to implement. To highlight the applicability of the model, a setup b...
Article
The introduction of 5G mobile networks, bringing multi-Gbit/s user data rates and reduced latency, opens new opportunities for media generation, transport and distribution, as well as for new immersive media applications. The expected use of millimeter-wave carriers and the strong network densification resulting from a much reduced cell size--which...
Conference Paper
Confidential wireless transmission of a 150 Mb/s chaotic encoded signal with an artificial signal to noise ratio of 0 dB is experimentally demonstrated at 28 GHz. The chaos is generated by a digitally implemented Duffing oscillator system.
Conference Paper
Chromatic dispersion in a large core-count 3-mode fiber is analyzed, observing up to 0.75 ps/(nm-km) variations between mode groups. Furthermore, digital CD compensation is shown to relax the stringent path length matching required in such systems.
Conference Paper
With the digitalization of industry and society, data centers have grown into an essential key strategic infrastructure, centralizing the processing, storage and distribution of vast amounts of information. Through continuing centralization, their size grows ever larger, while at the same time they need to remain flexible and dynamic to adapt to th...
Conference Paper
Analog radio-over-fiber transmission and millimeter-wave and terahertz signal generation through photonic heterodyning are a valuable and versatile solution for many applications. This talk will discuss recent advances, focusing 5G networks, wireless communications and sensing applications.