Integrated Wireless-pon access Network Architectures Milos Milosavljevic

Chapter 8 Project Achievements and Future Work 
167 
[20] W. Hofmann, E. Wong, G. Bohm, M. Ortsiefer, N. H. Zhu, and M. C. Amann, "1.55-um 
VCSEL Arrays for High-Bandwidth WDM-PONs," 
Photon. Technol. Lett.
, vol. 20, pp. 
291-293, (2008). 
[21] 
ACCORDANCE: A Converged Copper-Optical-Radio OFDMA-based access Network with 
high Capacity and Flexibility 
(Online). Available: http://ict-accordance.eu 
[22] 
ACCORDANCE: Deliverable 2.1 (D2.1) 
(Online). Available: http://ict-accordance.eu 
[23] 
Fibre-Optic Networks for Distributed Extendible Heterogeneous Radio Architectures and 
Service Provisioning (FUTON) 
(Online). Available: http://www.ict-futon.eu 
[24] 
Common Public Radio Interface (CPRI); Specificaiton v4.1
, http://www.cpri.info, 2009 

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168 
 Appendix
A
A
Appendix A presents the MATLAB coding for wireles trancreceivers as well as multupath 
channel modelling. These models were used throughout the thesis for WiMAX signal 
generation and reception as well as for radio channel evaluation. Aspects of the this coding 
have been presented in [1]. Modifcations are included here to adopt the program to the 
proposed simulation platform.
 
A.1
 
MATLAB Coding for Co-Simulation with VPI
A.1.1 WiMAX OFDM Transmitter 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% %
%% Name: ofdm_tx.m %
%% %
%% Description: It generates OFDM symbols by performing symbol mapping%
%% and IFFT. It also adds CP and multi-path channel if needed. The % 
%% output is fed to the VPI cosimulation interface %
%% %
%% %
%% Parameters:
% 
%% %
%% TimeWindow, BitRate, NFFT, BitPerSymbol, CyclicPrefix, BitStream= %
%% are passed from the VPI 
%
%% Cx=output complex IQ symbols data_mapped=mapped symbols %
%% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
function
Cx=ofdm_tx(TimeWindow,BitRate,Nfft,BitPerSymbol,CyclicPrefix,BitStream)
OFDM=[];
% 
% SUI=4;
% BW=10; %enabled only in upstream 
% 
% channel=channelSUI(SUI, CyclicPrefix, BW); % see A.3 for ch modelling
FrameLength=floor(Nfft*(1+CyclicPrefix));
NFrames=ceil(TimeWindow*BitRate/BitPerSymbol/FrameLength);
for
i=1:NFrames

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169 
data_mapped=cod(BitStream((i-
1)*BitPerSymbol*Nfft+1:i*BitPerSymbol*Nfft),BitPerSymbol);
%symbol mapping
ofdm_symbol=sqrt(Nfft).*ifft(data_mapped,Nfft);
margin=length(ofdm_symbol)*CyclicPrefix;
SymbolTx=[ofdm_symbol((end-margin+1):end) ofdm_symbol]; 
%cyclic prefix 
adding
%Channel effect (enabled for upstream transmission)
% NextSymbol = 8 .* sqrt(Nfft) .* ifft(randint(1,Nfft));
% SymbolTx = [NextSymbol NextSymbol SymbolTx]; %introduce ISI
% symbol_channel = filter(channel,1,SymbolTx); %apply multi-path ch
% symbol_channel = symbol_channel(end-(256*(1+CyclicPrefix))+1:end); 
OFDM=[OFDM SymbolTx]; 
%concentating OFDM symbols 
end
Cx=OFDM(1,1:TimeWindow*BitRate/BitPerSymbol); 
%ensuring sample rate 
consistency with VPI