Nathan J. Gomes

Learn More
It has become apparent that current fronthaul technology cannot be simply extended to meet the projected demands of 5G and beyond mobile systems. This current technology, based on the transport of sampled radio waveforms, has been the preferred option, with analog radio over fiber reserved to relatively niche application scenarios. However, for future(More)
This paper investigates performance impairments due to constraints imposed by the MAC layer when single-mode fiber (SMF) is used to extend the reach of an IEEE 802.11 network. It is shown that data throughput decreases as fiber length increases. It is also noted that the network fails long before physical layer limitations set in due to the timeout values(More)
Analog radio over fiber (RoF) links may offer advantages for cloud-Radio Access Networks in terms of component cost, but the behavior of the distortion with large numbers of subcarriers needs to be understood. In this paper, this is presented in terms of the variation between subcarriers. Memory polynomial predistortion is also shown to compensate for RoF(More)
The effect of distortion on the error vector magnitude (EVM) performance of orthogonal frequency-division multiplexing (OFDM) signals with different numbers of subcarriers and the connection to the peak-to-average power ratio (PAPR) of such signals is investigated. A low-cost and low-complexity directly modulated radio-over-fiber link is used in experiments(More)
This paper jointly optimizes the precoding matrices and the set of active remote radio heads (RRHs) to minimize the network power consumption (NPC) for a user-centric cloud radio access network (C-RAN), where both the RRHs and users have multiple antennas and each user is served by its nearby RRHs. Both users’ rate requirements and per-RRH power constraints(More)
The growing importance of wireless communications has been driving the research and development of advanced network architectures to enable the cost-effective support of large numbers of users at very high data rates. In this context, the FUTON project aims to fulfil the objectives of the so-called 4th Generation (4G) wireless communications through(More)