Integrated Wireless-pon access Network Architectures Milos Milosavljevic

7.1 Network Architecture 
 
A detailed diagram of the network architecture [1], incorporating the developed experimental 
setup is shown in Figure 7-1 (a snapshot of the set-up is included in appendix C.1). It has been 
previously established that inter-modulation products and link noise associated with the 

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Chapter 7 Experimental Investigation of WiMAX Transmission over Multi-Wavelength PONs 
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transmission over the optical path could degrade the received radio signal quality at the remote 
base stations. VPI with MATLAB modelling results have confirmed EVM figures below -30 dB 
and -24 dB for downstream and upstream WiMAX channels respectively over 20 km of legacy 
PONs. The obtained EVM figures are in compliance with the WiMAX standard concluding that 
the optical fibre has negligible effect on the received WiMAX channels for certain drive powers 
of the MZM and drive currents of the DFB laser [2].
Figure 7-1: WiMAX over multi-wavelength splitter-PON and experimental setup 
The experimental set-up portrays the key characteristics analysed in chapters 5 and 6 with the 
application of RoF by means of FDM to address individual base stations sharing a single 
wavelength being in the focus. To implement the ONU/BSs low-cost, long-wavelength VCSEL 
arrays and add/drop multiplexer, in the absence of a tuneable optical BPF, were employed.
Transmission of the combined wireless/optical signals over the wavelength band overlay PON 

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was accomplished by the use of PXI Aeroflex [3] WiMAX transceivers, the specifications of 
which will be presented in subsequent sections.
7.2 Experimental Setup 
In this experiment the mobile WiMAX IEEE802.16e specifications were consulted [4]. To that 
extent, this section emphasise on the generated WiMAX signals principle characteristics as well 
as the implemented experimental set-up backhauling the wireless channels over legacy PONs.