E. Tangdiongga

• Eindhoven University of Technology

We demonstrated maximizing transmission capacity and defining discrete and continuous coverage boundaries in an optical attocell network, utilizing bit-rate adaptation. This approach accounts for beam profile and aberration-induced coupling losses in wavelength-tunable beam steering. 1. Introduction In 6G, ultra-fast and large-capacity data communi...

By spatially modulating the wavefront, light can be controlled to focus through scattering media, enabling applications in biological sensing, non-line-of-sight (NLOS) imaging, and optical wireless communication. However, conventional liquid crystal-based spatial light modulators (LC-SLMs) and digital micromirror devices (DMDs) operate at refresh r...

In this paper, we present recent advancements in transmitter and receiver technologies for Optical Wireless Communication (OWC). OWC offers very wide license-free optical spectrum which enables very high capacity transmission. Additionally, beam-steered OWC is more power-efficient and more secure due to low divergence of light. One of the main chal...

The receivers for Optical Wireless Communication (OWC) need to meet the requirements for high-capacity data transmission. Photonic Integrated Circuits (PIC) allow the separation of light collection and light detection. In this way, both can be optimized separately. Light can be coupled into a PIC from free space through a surface grating coupler an...

Optical wireless communication employing narrow but steerable laser beams is an emerging technology to realize high-capacity indoor communications, given robust beam pointing and advanced transceivers. We discuss a prototype system and present results from a typical indoor link.

We transmitted 5.7 Tb/s over a 4.6 km free-space optical link in an urban environment, spanning the city of Eindhoven, the Netherlands, using a 1.1 THz wide wavelength-division multiplexed signal.

We designed and fabricated metasurfaces acting as a Dammann vortex grating or a mirror at two orthogonal polarizations. The metasurface concurrently supports both optical MUX/ DEMUX and routing, paving the way for reconfigurable indoor OWC networks.

Speckle patterns generated as coherent optical beams are reflected by scattering elements. Multimode fibers (MMFs) can modify the transverse intensity distribution of speckle patterns with macro perturbations, i.e., pressures, providing a simple and low-cost way to achieve equivalent beam-steering for indoor optical wireless communications (OWCs) w...

We propose the use of an IMOS surface grating coupler for light collection and commercial pigtailed receivers for light detection in short-link OWC system. We demonstrate error-free OOK transmission of four 25 Gbps WDM channels.

In this paper, we propose a compact optical wireless receiver based on micro-lens and photodiode array flip-chipped on a glass interposer. With simulation models and experiments, we verify the performance of two optical wireless communication receivers assembled based on this structure with gigabit and high-speed photodiodes. First, co-integrated g...

The predominant focus of research in high-speed optical wireless communication (OWC) lies in line-of-sight (LOS) links with narrow infrared beams. However, the implementation of precise tracking and steering necessitates delicate active devices, thereby presenting a formidable challenge in establishing a cost-effective wireless transmission. Other...

We present a novel indoor communication network using 1-mm core diameter step-index plastic optical fibres as a feeder line, and using the light emitted by the POF-end for wireless data transmission, creating a fully passive access point (AP). This has the advantage that it does not require electrical powering, resulting in low maintenance. Due to...

An all-fibre beam steering solution, based on mode coupling in 240-µm core size POF, is presented. Using DMT modulation over 90-cm wireless link and steering full angle of 9°, a throughput of 1.6 Gbps is achieved for visible light.

Communication for the Internet of things (IoT) currently is predominantly narrowband and cannot always guarantee low latency and high reliability. Future IoT applications such as flexible manufacturing, augmented reality and self-driving vehicles rely on sophisticated real-time processing in the cloud to which mobile IoT devices are connected. High...

This paper presents a novel concept for spatial diversity using plastic optical fibre (POF)-based luminaire transmission for in-home networks. We show the feasibility of an optical transmission system using POFs, acting as optical front-haul, for realizing a high capacity wireless bidirectional link aided by a spatial diversity scheme allowing user...

The Internet of Things currently is predominantly narrowband and cannot always guarantee high reliability and low latency. Future IoT applications such as flexible manufacturing, augmented reality and self-driving vehicles need sophisticated real-time processing units in the cloud to which mobile IoT devices are connected. These high-capacity links...

A spatial diversity scheme using 1mm core size plastic optical fibre as luminaires with 1.2m free space is experimentally evaluated. Discrete multitone and pulse amplitude modulation on a red wavelength demonstrate throughputs of 3.3Gbps.

We developed a new auto-aligned optical wireless receiver for indoor mobile users using a dual-axis actuator, a motion sensor, and a feedback control. Experiments demonstrate seamless transmission at normal walking speeds with <400ms alignment time.

With the increasing number of wireless devices interconnected, the radio spectrum is becoming congested. One of the main technologies used to ease the pressure on this spectrum is the optical wireless communication (OWC). OWC offers high bandwidth and makes use of unlicensed spectrum. Among the OWC solutions, a promising one is visible light commun...

This paper shows the feasibility of a networked LiFi system using a distributed multiple-input multiple-output (MIMO) link for optical wireless transmission and a plastic optical fiber (POF) link as a fixed front-haul between distributed optical front-ends, and a centralized signal processing unit. The concatenation of POF and optical wireless link...

Optical Wireless Communication (OWC) is an important alternative option that could ease the pressure on the radio spectrum that is now in use for communication. There are several OWC technologies that offer a promising solution for indoor wireless broadband communication over a distance up to a few meters. Potentially, OWC is suitable for very high...

We present upstream signaling and localization for an indoor beam-steered OWC system using vision-based technology. We demonstrate a 1.2kbps upstream signaling and localization system which enables to identify a large number of users with <0.05° error.

Most in-home, office and even industrial applications require simple maintenance, low-cost installation and upgradability in the future. These scenarios have a heterogeneous network, composed by a mix of wireline and wireless technologies, twisted-pair copper lines for telephones, Wi-Fi, multi-media on coaxial cable (MoCA) etc. Several network infr...

A wide-scan and broadband focal-plane array (FPA) concept is introduced in this article, which provides high antenna gain and effective isotropic radiated power (EIRP) with electronic beamsteering within a relatively large field of view (FoV), up to +/-20°. The antenna uses a bifocal double-reflector concept that optimizes the illumination of the f...

To develop an indoor optical wireless communication (OWC) system, both the system complexity/cost and data rate need to be taken into consideration. In this Letter, a cost-efficient half-duplex OWC system for photonic home area network applications is proposed and experimentally demonstrated. A low-cost Fabry–Perot laser diode is proposed to be emp...

A photonic beamformer system designed for next-generation 5G new radio (5G NR) operating in the millimeter waveband is proposed and demonstrated experimentally, including its performance characterization. The photonic beamforming device is based on optical ring resonators (ORRs) implemented on Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...

Beam steering demonstration employing integrated optical ring resonators (ORRs) and multi-core fiber with multiple beams at 17.6 GHz and 26 GHz obtains 103.5° beam separation. A 5G system with 4x1 beamforming at 26 GHz provides up to 16.8 Gbps with 20° beam steering.

A beamforming chip is realized on indium phosphide (InP) employing cascaded optical ring resonators and switched delay lines for wide bandwidth applications. 6.7 Gbps transmission in the K-band (17-22 GHz) is achieved up to 23.1 ps steering on a 4 GHz-wide OFDM signal.

By creating polarization orthogonality between the odd and even channels, crosstalk-free OWC link is realized with spectral overlap. This technique can tolerate the wavelength misalignment between AWGRs and lasers, which relaxes the design of high port-count AWGRs and wavelength stable lasers.

We report on a novel all-optical system for ultra-high capacity indoor wireless communication with centralized light sources. Using optical cross-connect and reflective modulator photonic chips, bidirectional dynamic indoor wireless networks equipped with localization and tracking functionalities are realized. This novel system allows us to harvest...

We propose a full-duplex dynamic indoor optical-wireless communication system using a crossed pair of diffraction gratings and photonic-integrated circuits with multicasting capability of 10-Gb/s on-off -keying and >40-Gb/s discrete-multitone data per user, backed up by a 60-GHz radio fallback system, with shared capacity of ∼40 Gb/s to realize re...

This paper presents successful simultaneous transmission of an IEEE802.11n 16-QAM 40 MHz WLAN, 9 bands 64-QAM LTE-A, and a baseband 1.7 Gb/s 4-PAM signal over 50 m of 1 mm core diameter graded-index polymethyl methacrylate plastic optical fiber. The optical link is an intensity modulation with direct detection link, using a Fabry Perot laser diode...

Free-space narrow infrared beams can offer unprecedented data capacity to devices individually, as they can provide non-shared connections that have a large link power budget. By means of a fully passive module based on a high port count arrayed waveguide grating router (AWGR), many infrared beams can be 2D steered individually using wavelength tun...

Non-uniform PAM utilizes unequal distances between its modulation levels. In a multilevel PAM symbol, multiple bits are encoded. Due to the unequal level spacing some bits can be decoded successfully at a lower received optical power than others. This is well suited for practical PON deployments wherein the optical powers received by the different...

We demonstrate a hybrid radio-optical wireless communication system using a photonic integrated all-optical-cross-connect (OXC) chip to realize a highly reconfigurable and reliable bidirectional indoor wireless network which provides the ultimate capacity per user. By remote wavelength-tuning, narrow optical beams are directed to the users employin...

Beam forming using a 4x1 phased array with an optical feed network for K-band smart antenna systems is presented. Up to 45 degree steering angles are achieved. Wireless transmission throughputs of up to 3 Gbit/s using 32-OFDM subcarriers are achieved for the attained steering angles.

By implementing optical carrier reuse concept, we demonstrate a novel full-duplex optical-wireless communication system using a reflective-modulator chip at the user terminal, equipped with localization/tracking functionalities, with unshared symmetric capacity of up to 40Gb/s.

FourWireless-Sensors-Network channels were transmitted over 50m GI-POF and 12m wireless together with a WLAN signal, 9 64-QAM LTE-A bands with reduced PAPR, and 1.66Gb/s 4-PAM baseband signal for multi-standard wired-wireless smart-home and in-home networks.

An optimized double-reflector antenna concept for a wideband focal plane array (FPA) configuration is presented for Ka-band applications with a limited scan range, e.g. ground terminals for satellite communication. The proposed reflector configuration allows to maximize the number of active array elements and minimize the actual array size during s...

We propose and demonstrate a novel bi-directional free-space (FS) optical wireless communication system for indoor wireless networks. A 2D infrared beam-steered system supporting full-duplex communication of at least 10 Gbit/s capacity per wireless terminal with simple NRZ-OOK modulation format is experimentally demonstrated. The uplink (UL) is imp...

A signal-to-interference-plus-noise-ratio-based (SINR-based) equalization scheme is proposed and tested for co-transmission of 8 bands 64-QAM LTE-A signal and a 1.8Gb/s 4-PAM signal over 50m of 1mm core diameter GI-POF and 3.5m wireless for in-home networks.

An optically controlled multi-RF beamformer for targeting more than one satellite is presented. Two beams in K-band of 6 Gbps each are generated by a 2x1 beamformer attached to a wavelength-dependent ring-based optical chip.

Duobinary-PAM3 enables up to 37.5Gb/s with 10G receivers. It has less linearity requirements on transmitters and gains 2dB sensitivity compared to equal-bitrate PAM8. In a 10G flexible modulation scheme, DB-PAM3 enables 190% network utilization increase.

The use of a 35 GHz reflective electroabsorption modulator (REAM) monolithically integrated with a semiconductor optical amplifier (SOA) for indoor wideband analogue applications is demonstrated. Unlike REAMs, good performances over a wide range of input optical power and wavelength are observed, which mitigates the need for accurate control of the...

Free-space indoor optical communication deploying pencil beams can offer ultra-high wireless capacity individually per user device. By means of two-dimensional (2D) diffractive modules, such as a pair of crossed gratings, 2D steering of multiple beams by just tuning the wavelength of each beam can be achieved. The design aspects of an indoor system...

In this paper we present the design, realization, and experimental characterization of a photonic integrated true time delay circuit on a CMOS-compatible Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/...

This letter presents the transmission of eight standard compliant 64-QAM long term evolution advanced (LTE-A) bands and 1.4 Gb/s 4-pulse amplitude modulation (PAM) signals over 20 m of 1 mm core diameter graded-index polymethyl methacrylate plastic optical fiber. The optical transceiver consists of a red light VCSEL and a p-i-n photodiode followed...

Current passive optical networks (PONs) use on–off keying (OOK) modulation throughout the entire network regardless of actual path losses. Statistics of commercial gigabit passive optical network (GPON) deployments show significant path loss differences among the optical network units (ONUs). Flexible 4- and 8-level pulse amplitude modulation (4/8-...

In order to circumvent radio spectrum congestion, we propose an innovative system which can provide multiple infrared optical wireless beams simultaneously where each beam supports multi-gigabit-per-second communication. Scalable two-dimensional beam steering by means of wavelength tuning is proposed. A passive beam-steering module constructed with...

This paper reports the experimental results of the co-transmission of a multi-band LTE-A and gigabit/s baseband 4-PAM signals over 35 m and over 50 m of 1 mm core diameter PMMA GI-POF, using low-cost components. Both links used a red light 650nm laser diode and p-i-n photodiode with transimpedance amplifier. The 4-PAM transmission achieved 1.2 Gb/s...

The transmission of multiple standard-compliant long-term evolution advance (LTE-A) bands together with a 4-pulse amplitude modulation (PAM) baseband signal over 50-m-long 1 mm core diameter polymethyl methacrylate graded-index plastic optical fibre is demonstrated. Transmission of eight LTE-A 64-QAM bands and a 1.2 Gbit/s 4-PAM baseband signal ove...

We designed and fabricated a Silicon Nitride (Si3N4) photonic integrated circuit targeting wideband two-dimensional radio beamforming from 20–40 GHz for satellite communications. Continuous true time delay tunability is achieved by using thermo-optic phase shifters in a 2-port optical ring resonator. Scanning angles up to 20° and true time delay ba...

We designed, fabricated and tested a compact AWG-based true-time delay chip for optically-assisted radio beamforming. Beam steering is performed remotely by only tuning the laser wavelength. We demonstrated beamforming of a 2.5-Gbps, 10 GHz signal with 2.7 o /nm discrete-step beam steering.

Cost, performance and energy consumption are major issues in indoor optical wireless systems. We propose a low cost, energy-friendly and yet high performance solution based on optical beam-steering and time-sharing. This solution also enables unicasting, multicasting and broadcasting of broadband services.

The actual use of power budgets in a PON typically varies widely. Utilizing 4-PAM modulation for ONUs that have high power margins can increase network capacity utilization without investing in expensive optics. We demonstrate that the capacity can increase 79%.

A compact and fabrication-tolerant integrated remotely tunable optical delay line is proposed for millimeter-wave beam steering and is fabricated in an InP generic foundry. The proposed delay line is based on a spectrally cyclic-arrayed waveguide grating feedback loop. Its major features include the tolerant architecture with reduced chip size, and...

Millimeter wave (mmWave) communication is being seen as a disruptive technology for 5G era. In particular, 60 GHz frequency band has emerged as a promising candidate for multiGbps connectivity in indoor and hotspot areas. In terms of network architecture, cloud radio access network (CRAN) has emerged as the most promising architectural alternative...

To combat the imminent radio frequency spectrum crunch, we propose an infrared optical wireless communication solution for in-home networks, with remotely controlled 2-dimensional passive optical beam-steering, which exhibited 42.8 Gbit/s over 2.5 m free-space transmission.

When dealing with lossy networks, performance management through conventional Quality of Service (QoS) based methods becomes difficult and is often ineffective. We find, in fact, that in this case quality emerges as an end-to-end factor, for it is particularly sensitive to the end-user perception of the overall service. To better explore the va...

The need for indoor wireless connectivity is increasing, and conventional systems are getting congested in the radio spectrum. A promising solution is an indoor network consisting of many radio pico-cells fed via fiber. We propose a low-cost implementation by deploying Radio-over-Fiber techniques. The remote antenna contains only an optical-to-elec...

A hybrid fiber-wireless in-home network is proposed to support high-speed multiple input and multiple output (MIMO) orthogonal frequency division multiplexing systems operating at millimeter wave (mm-wave) band by employing optical heterodyne (OH) and polarization multiplexing (PolMux). OH enables the optical generation of mm-wave signals without t...

We report a novel optical wireless communication (OWC) system solution that supports multi-Gbps (Gigabit-per-second) capacity for indoors. Narrow beams, termed as pencil beams, are directed to wireless users using a tunable laser and a passive diffractive optical element. This enables a wide coverage of ultra-high-capacity communication links to se...

We propose a novel spectrum-efficient indoor optical wireless solution providing multi-Gigabits-per-second with passive diffractive beam-steering technique and discrete multitone modulation. Diffracted link performance of 36.7 Gbps over more than 2.5 m is reported.

The electrically-controlled optical phase shifter (ECO-PS) is proposed and experimentally investigated for broadband radio orbital angular momentum mode generation. ECO-PS can offer the same advantages as optical true time delay schemes while avoids their phase-frequency dependence.

The current explosion of communication traffic volume is driven by an insatiable appetite for high speed internet connectivity and video-based content delivery to wireless and mobile terminal users, especially for in-home scenarios. A lot of research has been carried out to exploit wireless capacity. In the spatial domain, spatial multiplexing, spa...