Integrated Wireless-pon access Network Architectures Milos Milosavljevic

Chapter 8 Project Achievements and Future Work 
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8.2 Achievements 
In order to meet the above challenges, this work introduced a novel hybrid optical access 
network architecture. It is intended not only to offer mobility over TDMA-PON solutions but 
also inherently provide the opportunity for convergence between optical and radio access, 
supporting seamless ubiquitous broadband services. The architecture provides a variety of 
desirable network characteristics, like high bandwidth backhauling links, increased radio 
spectral efficiency and scalability, enhanced resource allocation flexibility, lower equipment 
cost/complexity and reduced power consumption, while supporting multi-wavelength operation. 
In that direction, this thesis has provided the justification, design criteria, implementation and 
evaluation both in the form of a comprehensive VPI/MATLAB simulation platform and test-
bed experimentations for an innovative approach employing RoF transmission [19] 
complemented with FDM to address individual simplified remote base station antennas.
Extended wireless network features in the form of overlapping cells were also evaluated to 
enhance the capacity and provide network resilience. 
The property of the network to use FDM also added to the network dynamicity since multiple 
subcarriers could be dropped to a single base station thus increasing its capacity. This can be 
controlled centrally from the OLT. FDM also provides for wireless signal transparency avoiding 
interference with the legacy PON spectrum if transmitted on the same wavelength. Therefore, 
this novel network is easily extendable to support emerging broadband wireless standards 
including LTE and its upgrades.
A feature in upstream, is that ONU/BSs receive time-interleaved WiMAX channels, avoiding at 
the optical receiver in the OLT any potential OBI. This could, however, result in restricting the 
bandwidth utilisation efficiency for the wireless users. Also, a single wavelength approach 
could impose high dispersion penalties across the fibre as the number of frequency subcarriers 

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