Integrated Wireless-pon access Network Architectures Milos Milosavljevic

Chapter 8 Project Achievements and Future Work 
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exploiting the OFDM modulation concept [13]. To that extent, several key network elements 
that emerged from various research paths are used to enhance data throughput, such as the 
application of multiple antenna techniques (MIMO) [14], adaptive modulation and coding [13], 
and relay re-transmission for increased coverage [15]. Alternatively, utilisation of lower 
frequency bands, around 700 MHz, has also provided the potential to support even higher data 
rates due to the large available bandwidth at these frequencies [16].
However, in order to achieve gigabit spectral efficiency across a cell or a sector, densely 
populated base stations need to be deployed [17]. This would result in higher network 
deployment cost as the number of base stations required to cover a certain area is increased. 
Significantly, high capacity backhauling links are then needed to connect these base stations to 
ISPs.
The wireless/optical integration has been investigated in this direction as a potential low-cost 
solution, expected to have a large impact on the economics of near-term access deployment 
[17]. As a result, combining the merits of the high bandwidth xPON solutions with the mobility 
and flexibility provided by the cost-effective, wireless networks, effectively address the 
challenges of next-generation access networks articulated by transparency, smooth 
upgradability, scalability and dynamicity [18]. 
Since the projected network could facilitate the support of multiple operators and multiple 
technologies within the same infrastructure, it is expected to provide a natural environment for 
healthy competition among European network and service providers that will revitalize the 
European market and reinforce its competitiveness. 

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