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Next generation integrated fiber-wireless access networks will require low-cost and high capacity deployment to meet the customer demand. A new configuration of radio over fiber-passive optical network (RoF-PON) architecture, including two 60 GHz multiple-input multiple-output (MIMO) based on a 5G universal filtered multicarrier (UFMC) waveform and wired signal utilizing orthogonal frequency division multiplexing (OFDM), is described. At the optical line terminal MIMO signals are integrated as upper and lower sidebands of the wired OFDM signal. This integration approach employing single sideband frequency translation (SSB-FT) reduces the complexity of the transceiver design and provides high spectral efficiency because the two MIMO-RoF and wired signals transmit at the same frequency. Improved techniques are also employed to upconvert and downconvert the 60 GHz millimeter wave (MMW) being remote optical heterodyning and self-heterodyne, respectively. The MIMO-RoF signals are therefore transmitted at low frequency over the standard single mode fiber to avoid the impairments induced at higher frequencies and the remote optical local oscillator is reused to downconvert the two 60 GHz MMWs producing a costeffective system. Simulation results demonstrate very satisfactory network performance when using a downstream link over a 20 km span standard-PON.

Saltwater intrusion has become a crucial issue for water resources management across the globe. Consequently, this issue leads to problems such as encroachment on water intake zone, loss of freshwater vegetation and also disturbance to aquatic life habitat. Undeniably climate change increases the saline water flow into the river system. The meandering rivers are common, and the hydraulics is more complex than straight rivers. An experimental hydraulic investigation was carried out in the Universiti Teknologi Malaysia to elucidate the hydrodynamic interactions between saline water and freshwater in a narrow meandering channel. The spatio-temporal salinity profiles along the river are discussed in this paper. The findings prevailed a typical characteristic of a salt-wedge estuary and indicated the processes of estuarine mixing. As the saltwater flows upstream, the salinity level drops due to the dilution process. Salinity levels and densimetric Froude number were mainly driven by freshwater discharge in the channel. A variation of dilution rate in a narrow meandering channel were up to 78.9% due to strong velocity forces produced by a high freshwater discharge. Furthermore, the flow resistance induced by the channel boundaries and meander planform itself influenced the salinity intrusion profiles along the channel.

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