Coverage Extension of Indoor 5G Network Using RoF-Based Distributed Antenna System

Abstract

We propose and demonstrate a cascaded distributed antenna system (DAS) for efficiently extending the coverage of the mmWave-based 5G indoor network. For this, we exploit the radio-over-fiber (RoF) system based on the intermediate-frequency-over-fiber (IFoF) transmission technique that is enabled to add/drop the specific wavelength to the designated remote antenna unit (RAU) with using optical splitters and coarse wavelength division multiplexing (CWDM) filters. Moreover, the IFoF transceivers (TRx) perform the subcarrier multiplexing (SCM) in order to transmit 2×8 frequency allocation (FA) 5G signals per a single optical carrier, where each FA has 100 MHz bandwidth, leading each RAU to support 2×2 MIMO operation. Consequently, the cascaded structure allows for the adaptive and flexible configuration of the order of MIMO in accordance of the required data throughput at the specific indoor area. We introduce the cascaded IFoF link structure that can support up-to 13.5 dB optical power budget with following error-vector-magnitude (EVM) performance characterizations. And then we experimentally demonstrate the RoF-based cascaded DAS network, showing that more than 1 Gb/s total throughput can be achieved per a single antenna. Furthermore, we examine the use of avalanche photodiode (APD) to further increase the optical power budget (i.e., the coverage) based on experiment as well as simulation.

Multi-Technology Multi-Operator Site Sharing: Compliance Distance Analysis for EMF Exposure

“…The operators install the IBS inside massive buildings and high-rise towers, where the received coverage from outdoor macro sites is weak due to the construction penetration losses. The IBS combines all the technologies into one Distributed Antenna System (DAS) in which each antenna provides coverage for a certain zone as a hotspot [ 17 , 40 ].…”

“…Site sharing has become a good alternative and a key approach because of the following main reasons [ 16 ]: It is less expensive to share a site than to build a new one. According to [ 17 ], infrastructure sharing can result in significant cost savings—up to 40% of assets can be saved by site sharing, and cash flow can improve by 31% as a result. The densification of the existing sites increases the difficulty of acquiring more physical sites within the required nominal locations and leads to fewer options.…”

“…It is less expensive to share a site than to build a new one. According to [ 17 ], infrastructure sharing can result in significant cost savings—up to 40% of assets can be saved by site sharing, and cash flow can improve by 31% as a result.…”

Electromagnetic field exposure boundary analysis at the near field for multi‐technology cellular base station site

“…Due to construction penetration losses, the operators install the IBS within huge buildings and high-rise towers where coverage from outdoor macro sites is challenging. The typical deployment of IBSs combines all the technologies in one distributed antenna system (DAS) in which each antenna provides coverage for a certain zone as a hotspot [42,43].…”

Fibre Wireless Distributed Antenna Systems for 5G and 6G Services

“…The combined RF signal power was set at approximately 10 dBm. The optical link consists of a single-mode fibre (SMF) with a length of 10 km, followed by the variable optical attenuator (VOA) that incorporates the optical coupler to achieve the cascade architecture [33]. Instead of using an optical coupler, a Diplexer (DPX) could also be used as DPX has an additional advantage in that it is frequency selective and will divide the signals accordingly.…”