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A multi-Gb/s 28-GHz mmWave hybrid-beamforming system integrated with a 64- element antenna array fabricated on a Corning-glass-substrate is demonstrated. DSP-based adaptive-hybrid-algorithms are utilized to achieve both electronic beam-steering and multi-user operation with >23-dB inter-user interference suppression.

We experimentally demonstrate up to 10× greater system capacity using Distributed M-MIMO compared to Collocated M-MIMO in an indoor environment. We further show that user-distribution-driven antenna placement enables significant infrastructure savings up to 25%.

We present the performance evaluation of impulse radio ultrawideband (IR-UWB) over fiber using a simple pulse design technique with a high fractional bandwidth. The technique, based on the linear combination of the first-order Gaussian derivatives with different pulse-shaping factors, shows full compliance with Federal Communications Commission mask requirements even in the most severely power-restricted GPS band. We validated our approach with experiments employing an intensity-modulation direct-detection scheme. The experimental setup uses a directly modulated DFB laser at 1302.56 nm and a multimode fiber-coupled photodetector with 24 μm diameter photosensitive area. The transmission link consists of 25 km single-mode fiber or 4.4 km multimode fiber. Error-free transmission at 2 Gb/s is achieved over both fiber links. The result shows the proposed pulse-generation technique to be simple and cost-effective compared to higher order Gaussian derivative schemes. This can be implemented successfully to distribute UWB signals over optical links for access and in-building networks.

Energy efficiency has become a major paradigm in the design and operation of future telecommunication networks. Recent studies show that the aggregate power consumption of in-building IT networks (residential and office) is massive and comparable with that of data centers due to the large number of buildings. In this paper, we analyze the energy efficiency of next-generation in-building IT networks to deliver high-speed mobile access to end users via integrated optical/wireless networks using Radio-over-Fiber (RoF) technology. Based on a validated energy efficiency model, our results show that although individual point-to-point RoF links are not as energy efficient as legacy Baseband-over-Fiber links, RoF networks may actually be more energy-efficient when designed keenly with small cells sizes and when the static energy consumption of the remote units is above a particular threshold. Under the assumptions used in this paper, we show that the DRoF-based architectures can be designed to more energy efficient for cell sizes

Within a decade a 1000-fold increase in wireless communication traffic volume is expected, requiring increased throughput and data rates. Although the Terahertz (THz) band offers new possibilities it remains largely unexplored. Spectrum frequencies over 300 GHz are as yet unallocated but could fulfill the demand for wireless data transmission, e.g. in terms of available bandwidth. The fabrication of new cutting edge technology and the development of novel THz mobile communication systems are key to explore the spectrum at these frequencies and in order to achieve connectivity requirements of future mobile systems beyond 5G. This paper will report on novel coherent radio over fiber (CRoF) technologies for Terahertz transmission systems. World record experimental results for Terahertz transmission will be reported.

We demonstrate below FEC-limit (BER

We present a wireless link budget analysis for impulse-radio ultrawideband (IR-UWB) systems with different pulse-shaping techniques using a realistic path loss model. Simulation results confirm that a proper pulse design technique is crucial for satisfying Federal Communications Commission mask requirements and performance enhancement of IR-UWB systems. We present a novel pulse design technique, based on a linear combination of modified doublets pulses and compare it with conventional pulses such as monocycle, doublet and fifth-order derivative of Gaussian pulses. The proposed pulse outperforms the conventional pulses in terms of spectral power efficiency and achievable reach using an M-ary pulse-amplitude modulation format and a fixed data rate. Furthermore, we propose and experimentally demonstrate routing over a hybrid wired-wireless network of IR-UWB services using the proposed pulse shape. The routing functionality is realized using a single semiconductor optical amplifier based on the cross-gain modulation technique. Error-free transmission of both 1.25 Gb/s baseband wired services and 2 Gb/s wireless IR-UWB services has been achieved over 1 km fiber link. The proposed technique can efficiently distribute and multicast both wireless IR-UWB and wired services in future in-building networks.

Future in-building networks will most likely consist of two segments - optical and wireless; they will use little or no copper media. In previous work, we've analysed a number of green optical/wireless in-building network designs. In this paper, we present a study of why, where and how these networks can be deployed. We consider three different technologies: legacy Baseband-over-Fiber, Analog Radio-over-Fiber and Digital Radio-over-Fiber, in two different deployment scenarios: indoor networks and high user density open space/outdoor networks. We also consider two different deployment goals: improved coverage and increased capacity. Our results indicate that for indoor networks cell sizes should be between ∼10 m – 15 m with DRoF technologies while for high user density outdoor/open-space networks, cell sizes 80 m for open space buildings).

Radio-over-Fiber (RoF) based network architectures would allow centralization of signal processing and signal conditioning functions and simple, cost-effective remote units at the cell site. RoF technology results in remote units with few components, however, certain aspects of the technology may inadvertently lead to high power consuming components. In this paper, we experimentally investigate the effect of electrical-optical-electrical (E/O/E) loss and signal bandwidth on the energy consumption of analog and digitized RoF (ARoF and DRoF) links. We also analyze the energy efficiency of multiple services on a single RoF distribution network. Our results show that E/O/E loss significantly degrades the energy efficiency of the ARoF links. DRoF is robust to the E/O/E loss on the optical link but is affected by the loss due to reconstruction of the radio frequency signal at higher Nyquist zones. We also show that increasing the bandwidth improves the energy efficiency. Finally, we demonstrate that the extra energy savings from having multiple services on a single RoF link depends on the wireless environment.

With the growing popularity of high-performance computing devices such as tablets and smart-phones, and the growing trends of cloud-based services, forecasts indicate that the majority of Internet traffic will originate from inside of the buildings. Thus indoor network infrastructure needs to provide both better capacity and better coverage. Meanwhile, energy efficiency of the network becomes an additional requirements on the network design, due to the rising concern of the carbon footprint of telecommunication industry over the past few years. In this paper, we discuss a few fundamental trade-offs that need to be considered when designing energy-efficient networks. We also discuss the energy efficiency of Radio-over-Fiber (RoF) links and compare RoF-based architectures with legacy Basebandover- Fiber (BoF) for two scenarios: growing network capacity and improving network coverage. We demonstrate that the understanding and the analysis of main energy hogs and their trade-offs in various network architectures is a key factor in optimizing the design of energy-efficient network architecture.

We propose a new and power-efficient impulse radio ultawideband (IR-UWB) pulse design concept. The proposed concept is based on a linear sum of modified doublet pulses. The proposed concept is both simulated and experimentally demonstrated. The experimental demonstration employs a photonic scheme that generates the designed pulse using two main steps, mainly optical shaping and differential detection. The optical shaping is performed using a single electro-optic modulator biased in the nonlinear portion of its transfer function, and the differential detection is performed using a balanced photodetector. The generated IR-UWB pulse is fully Federal Communications Commission compliant, even in the highly power-restricted global positioning system band. The proposed optical scheme has potential to be integrated on a compact optical chip and thus suitable for reliable, low-cost, high-speed, short-range UWB wireless access, such as in-building networks.

We demonstrate, for the first time, simultaneous routing of wireless 2 Gb/s IR-UWB and 1.25 Gb/s wired services using XGM-SOA. This technique has potential applications for integration of wireless and wired services for in-building networks.

We propose and demonstrate, for the first time, service multicasting by all-optical routing of 1 Gb/s IR-UWB using XGM of SOA. This technique has potential applications for integrating IR-UWB with WDM PON and in-building networks.

We report multigigabit/second transmission capacity in 1 mm core diameter graded index plastic optical fiber (POF) exploiting off-the-shelf low-cost components and discrete multitone (DMT) modulation. Transmission capacities of 10.1 Gbits/s x 15 m and 12.7 Gbits/s x 3 m are achieved for average bit-error rates less than 10(-3).

We propose a novel generation technique for IR-UWB signal employing the weighted sum of modified doublets. We experimentally demonstrate a DSP-based BER measurement of 2 Gbps IR-UWB over 100m PF GI-POF for in-building network applications.

Radio-over-fibre systems can efficiently deliver broadband wireless services in access and in-building networks. RoF signal transport and routing techniques are presented which are robust against fibre dispersion and provide capacity-on-demand for high-capacity multi-tone radio signals.

The use of a RoF scheme for localization purposes of mobile stations for in-house networks is presented. Using impulse radio UWB over SMF and time-of-arrival localization method, mobile stations can be localized within centimeters accuracy.

The use of a RoF scheme for localization purposes of mobile stations for in-house networks is presented. Using impulse radio UWB over SMF and time-of-arrival localization method, mobile stations can be localized within centimeters accuracy.

We propose novel generation technique of IR-UWB pulse by combining two monocycles using different pulse-shaping factors. We experimentally demonstrate DSP based BER measurement of 2 Gbps IR-UWB over 25 km single-mode fiber for access networks.

We propose novel generation technique of IR-UWB pulse by linearly combining two monocycles using different pulse shapes. We experimentally demonstrate DSP based BER measurement of 2 Gbps IR-UWB over multimode fiber for in-building networks application.

Exploiting an integrated micro-ring resonator, the simultaneous generation and routing of millimetre-wave signals by optical frequency multiplication is demonstrated for in-building networks. Error Vector Magnitude < 5% is achieved for up to 120Mb/s 64-QAM at 39.6 GHz carrier frequency.