%?The?codes?investigate?the?performance?of?a?greedy?algorithm?[1]?in?OFDM?which
%?allocates?the?power?to?subchannel?in?optimum?way?to?reach?the?required
%?Data?rate

%?By?Hamid?Ramezani?23-Mar-2008

%?setting?the?parameters
numOfSubChannels?=?16;????????%?number?of?subchannels
modBitRate???????=?[0;1;2;4;6];%?the?provided?bit?rate?bits/Hz/Sec?for?
???????????????????????????????%?example?based?on?BPSK?QPSK?16QAM?and?
???????????????????????????????%?64QAM?modulation
???????????????????????????????%?zero?is?required?to?states?that
???????????????????????????????%?subchannels?can?convey?no?data
???????????????????????????????
reqSNR?????????=10.^（.1*[-Inf;9;12;18;24]）;?
???????????????????????????????%?Reqired?SNR?for?the?receiving?the?
???????????????????????????????%?the?bits?through?modulation?on?10^-4?BER
???????????????????????????????%?condition?ref[2]
???????????????????????????????%?zero?is?required?to?states?that
???????????????????????????????%?subchannels?can?convey?no?power
???%Attention
????????%?The?single-side?noise?power?spectral?density?（N0）?is?assumed?to?be?1
????????%?otherwise?the?parameter?setting?must?be?modified
????????%?SNR?=?Pt*CSI^2/（N0*B/N）?which?is?assumed?to?SNR?=?Pt*CSI^2?（it?is
????????%?a?kind?of?normalization）
???????????????????????????????
requiredRate?????=?23;?????????%?bits/Sec/Hz


%?channel?coefficient?generation
????%?rayleigh?fading?channel?（with?Rician?absulute）
????CSI?=?1/sqrt（2）?*?abs?（?randn（numOfSubChannels1）?+?...
????????sqrt（-1）*randn（numOfSubChannels1））;

%?calling?the?mex?function
[subChannelrequiredPowersubChannelRate]?=?...
????greedyAlgSingleUser（requiredRateCSImodBitRate?reqSNR）;


%?Graphical?observation
????f1?=?figure（1）;
????set（f1‘color‘[1?1?1]）;
????subplot（221）
????????bar（subChannelRate）
????????xlabel（‘Subchannel?Indice‘）;
????????ylabel（‘number?of?bits?conveied?by?subchannels‘）;
????subplot（222）
????????bar（10*log10（subChannelrequiredPower））
????????xlabel（‘Subchannel?Indice‘）;
????????ylabel（‘amount?of?power?required?by?subchannels?in?dB‘）;
????subplot（223）
????????bar（20*log10（CSI））
????????xlabel（‘Subchannel?Indice‘）;
????????ylabel（‘channel?response?in?different?subchannels‘）;
????subplot（224）
????????bar（10*log10（subChannelrequiredPower./（CSI.^2）））
????????xlabel（‘Subchannel?Indice‘）;
????????ylabel（‘SNR?in?different?subchannels‘）;
????????
%?References
%?Ref[1]?C.?Y.?Wong?R.?S.?Cheng?K.?B.?Letaief?and?R.?Murch?“Multiuser
%????????OFDM?with?Adaptive?Subcarrier?Bit?and?Power?Allocation“?IEEE
%????????Journal?on?Selected?Areas?In?Communications?Vol.?17?No.?10
%????????OCTOBER?1999

%?Ref[2]?Y.?Zhang?and?K.?B.?Letaief?揗ultiuser?Adaptive?Subcarrier-and-Bit?
%????????Allocation?With?Adaptive?Cell?Selection?for?OFDM?Systems??IEEE?Transaction
%????????on?wireless?communications?Vol.?3?No.?5?Sep?2004

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????2913??2008-03-23?20:01??GreedyAlgOfdmExample.m
?????文件????????5803??2008-03-23?19:13??greedyAlgSingleUser.c
?????文件????????7168??2008-03-23?19:13??greedyAlgSingleUser.mexw32