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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.

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 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.

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 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.