Analysis of and compensation for non-ideal RoF links in DAS [Coordinated and Distributed MIMO]

2011 IEEE Vehicular Technology Conference (VTC Fall)

2011

Abstract-The achievable throughput of the entire cellular area is investigated, when employing fractional frequency reuse techniques in conjunction with realistically modelled imperfect optical fibre aided distributed antenna systems (DAS). Given a fixed total transmit power, a substantial improvement of the celledge area's throughput can be achieved without reducing the cellcentre's throughput. The cell-edge's throughput supported in the worst-case direction is significantly enhanced by the cooperative linear transmit processing technique advocated. Explicitly, a cell-edge throughput of η = 5 bits/s/Hz may be maintained for a imperfect optical fibre model, regardless of the specific geographic distribution of the users.

Section: Performance Evaluation a Simulation Assumptionsmentioning

confidence: 99%

Digital RoF Aided Cooperative Distributed Antennas with FFR in Multicell Multiuser Networks

Zhang

2011 IEEE Vehicular Technology Conference (VTC Fall)

2011

“…Radio over fibre systems constitute a cost effective solution for the interconnection of Base Stations (BS) or for feeding the so-called distributed antennas [1]. The BS typically employs a Photo-Detector (PD) for detecting the signals of other BSs received through the Mobile Switching Center (MSC).…”

Section: Introductionmentioning

confidence: 99%

Reduced Dispersion Duplex DQPSK Radio-Over-Fiber Communications Using Single-Laser-Based Multiple Side-Bands

Ghafoor

2011 IEEE International Conference on Communications (ICC)

2011

Abstract-Multiple side-bands are generated from a single laser diode with the aid of optical carrier suppression, which facilitates the transmission of reduced-rate parallel streams mapped to the side-bands. As a benefit, all the optical signal processing tasks, including demultiplexing of a high-rate signal into multiple low-rate signals can be performed at the central unit. The technique can also be useful in reducing the effects of dispersion in case of high-frequency Radio Over Fiber (ROF)communications by transmitting a single-data rate signal as multiple low-rate signals using the side-bands generated. We demonstrate the duplex transmission of a bit-rate of 768 Mbit/s over a 50 km fiber section using three side-bands in each direction. The multiple side-band aided system has a BER performance, which is close to that of the idealized benchmarker operating in a back-to-back mode.

“…DASs provide a high capacity per subscriber by re-using the same frequency band in all the adjacent cells [1]. In this scenario, the optical fiber backbone linking the Radio Access Units (RAUs) plays an important role as a benefit of its high bandwidth, transparency to RF signals and low attenuation.…”

mentioning

confidence: 99%

“…In this scenario, the optical fiber backbone linking the Radio Access Units (RAUs) plays an important role as a benefit of its high bandwidth, transparency to RF signals and low attenuation. Hence the RAUs are connected to a Central Unit (CU) by their optical fiber backbone and all the signal processing tasks can be performed at the CU, where the RAU antennas act as elements of a virtual Multiple Input Multiple Output (MIMO) architecture [1], as shown in Fig 1. Consider Link 1, which consists of two RAUs connected through two spans of optical fiber with a CU. The RAUs transmit RF signals at mm-wave to the Mobile Stations (MSs), which are connected to a particular RAU depending upon their received signal quality.…”

mentioning

confidence: 99%

Sub-Carrier-Multiplexed Duplex 64-QAM Radio-over-Fiber Transmission for Distributed Antennas

Ghafoor

2011

IEEE Commun. Lett.

Abstract-We demonstrate the feasibility of Radio Over Fiber (ROF) transmission of 4 Sub-Carrier Multiplexed (SCM) 64-QAM data streams to a pair of low-complexity Radio Access Units (RAUs), which form part of a virtual MIMO architecture under the control of a Central Unit (CU). The ROF signal is transmitted over low frequency RF carriers and heterodyne detection is used at the RAUs. The 4 coherent optical carriers used for data transmission as well as for heterodyning at the RAUs are generated using a single laser rather than several inevitably non-coherent lasers. Our proposed system transmits duplex data of 480 Mbit/s and 240 Mbit/s in the downlink and uplink directions, respectively at mm-wave frequencies of 25 GHz or 50 GHz.Index Terms-Radio-over-fiber transmission, distributed antennas, 64QAM.