function ttlist = etsi_loopsADSL(ttlist,len,selfdisturbers,namestr);
%% ===========================================================================
% etsi_loopsADSL - Define the ETSI ADSL testloops
%
% Parameter:    ttlist          List to insert the testloops
%               len             Length for loop 1 to 8    
%               selfdisturbers  Number of self disturbers in the loop
%               namestr         Name string extension
% Returns:      ttlist          List with inserted the testloops
%
% Example(s):
%   
% Algorithmic details:
%   
% Reference:
%    ETSI STC TM6 Draft TS 101 388 v1.2.1 (ADSL), 980p12a8, 2001-03
%    ETSI STC TM6 Draft RTS/TM-06006 rev 10a (ADSL), 2001-05
%% ===========================================================================

%% ===========================================================================
% Copyright (C):                                        
%       2001-2002 by Forschungszentrum Telekommunikation Wien, Austria;
%                                                         All rights reserved.
% Project       : B1, FTW, ADSL simulations
% Author(s)     : Tomas Nordstrom (Tomas.Nordstrom@FTW.at)
%
% CVS:       $Id: etsi_loopsADSL.m,v 1.2 2002/01/25 12:16:17 tono Exp $
%% ===========================================================================
% Change History
%      2001-07-03 (ToNo) Created
%      2001-07-05 (ToNo) Added support for same pair ISDN
%      2002-01-11 (ToNo) Moved support for same pair ISDN to another place
%      2002-01-11 (ToNo) Now uses parametric models for the cables
%% ===========================================================================

if nargin<2,
    len=1000;
end

if nargin<3,
    % For ADSL the self disturbers are included in the noise masks!
    selfdisturbers = 0; 
end
nomodems = selfdisturbers+1;

if nargin<4,
    namestr='';
end

if length(len) == 1
   len=len.*ones(1,8);
end

 % The lengths predifined in the loop defs
offsetlen=[0 0 1500 2200 1750 1750 4200 1100];
len=len-offsetlen;

len(find(len<0))=0;

%% ===========================================================================
% Loop #0 connects the transceivers back-to-back. This loop mainly
% stresses the analogue front end (AFE) and the dynamic range of
% the digital processing.
tt.name= sprintf('ETSI-ADSL-Loop0%s',namestr);             
tt.topology=[
    {0  '' 'CO' ''}; 
    {2  'ETSI-ADSL-PE04m'   'NT' '0km'};
    ];
tt.traffic=[
    {1 2 'ADSL' nomodems};
    ];
ttlist=insertList(ttlist,tt);


%% ===========================================================================
%Loop #1 is a single straight 0.4 wire that represents typical
%deployment scenarios. When the length of the loop is set to
%maximum reach this loops stresses the ADSL equipment similar to
%typical deployment.
tt.name= sprintf('ETSI-ADSL-Loop1%s',namestr);             
tt.topology=[
    {0  '' 'CO' ''}; 
    {len(1)  'ETSI-ADSL-PE04m'   'NT' sprintf('%.0fm ->',len(1))};
    ];
tt.traffic=[
    {1 2 'ADSL' nomodems};
    ];
ttlist=insertList(ttlist,tt);

%% ===========================================================================
%Loop #2 is a single straight 0.5 wire that represents typical
%deployment scenarios. When the length of the loop is set to
%maximum reach this loops stresses the ADSL equipment similar to
%typical deployment.
tt.name= sprintf('ETSI-ADSL-Loop2%s',namestr);             
tt.topology=[
    {0  '' 'CO' ''}; 
    {len(2)  'ETSI-ADSL-PE05m'   'NT' sprintf('%.0fm ->',len(2))};
    ];
tt.traffic=[
    {1 2 'ADSL' nomodems};
    ];
ttlist=insertList(ttlist,tt);

%% ===========================================================================

%Loop #3 consists of two segments of wires with different
%diameter that represents typical deployment scenarios. 
%When the length of the loop is set to maximum reach (-1.5km) 
%this loops stresses the ADSL equipment similar to
%typical deployment.

seglens=[len(3) 1500];
tt.name= sprintf('ETSI-ADSL-Loop3%s',namestr);             
tt.topology=[
    {0  '' 'CO' ''}; 
    {seglens(1)  'ETSI-ADSL-PE04m'   '' sprintf('%.0fm ->',seglens(1))};
    {seglens(2)  'ETSI-ADSL-PE05m'   'NT' sprintf('%.0fm ->',seglens(2))};
    ];
tt.traffic=[
    {1 3 'ADSL' nomodems};
    ];
ttlist=insertList(ttlist,tt);


%% ===========================================================================
%Loop #4 consists of four segments of wires with different diameter. 
seglens=[200 len(4) 1500 500];
tt.name= sprintf('ETSI-ADSL-Loop4%s',namestr);      
tt.topology=[
   {0  '' 'CO' ''}; 
   {seglens(1)  'ETSI-ADSL-PE032m'   '' sprintf('%.0fm ->',seglens(1))};
   {seglens(2)  'ETSI-ADSL-PE04m'    '' sprintf('%.0fm ->',seglens(2))};
   {seglens(3)  'ETSI-ADSL-PE05m'    '' sprintf('%.0fm ->',seglens(3))};
   {seglens(4)  'ETSI-ADSL-PE063m'   'NT' sprintf('%.0fm ->',seglens(4))};
];
tt.traffic=[
    {1 5 'ADSL' nomodems};
];
ttlist=insertList(ttlist,tt);

%% ===========================================================================
%Loop #5 consist of four segments of wires with different diameter.
seglens=[len(5) 750 500 500];
tt.name= sprintf('ETSI-ADSL-Loop5%s',namestr);      
tt.topology=[
   {0  '' 'CO' ''}; 
   {seglens(1)  'ETSI-ADSL-PE04m'   '' sprintf('%.0fm ->',seglens(1))};
   {seglens(2)  'ETSI-ADSL-PE05m'   '' sprintf('%.0fm ->',seglens(2))};
   {seglens(3)  'ETSI-ADSL-PE063m'  '' sprintf('%.0fm ->',seglens(3))};
   {seglens(4)  'ETSI-ADSL-PE09m'   'NT' sprintf('%.0fm ->',seglens(4))};
];
tt.traffic=[
    {1 5 'ADSL' nomodems};
];
ttlist=insertList(ttlist,tt);

%% ===========================================================================
%Loop #6 consist of three segments with different diameter.
seglens=[len(6) 1250 500];
tt.name= sprintf('ETSI-ADSL-Loop6%s',namestr);      
tt.topology=[
   {0  '' 'CO' ''}; 
   {seglens(1)  'ETSI-ADSL-PE04m'   '' sprintf('%.0fm ->',seglens(1))};
   {seglens(2)  'ETSI-ADSL-PE05m'   '' sprintf('%.0fm ->',seglens(2))};
   {seglens(3)  'ETSI-ADSL-PE063m'  'NT' sprintf('%.0fm ->',seglens(3))};
];
tt.traffic=[
    {1 4 'ADSL' nomodems};
];
ttlist=insertList(ttlist,tt);

%% ===========================================================================
%Loop #7 consist of three segments with different diameter.
seglens=[200 len(7) 4000];
tt.name= sprintf('ETSI-ADSL-Loop7%s',namestr);      
tt.topology=[
   {0  '' 'CO' ''}; 
   {seglens(1)  'ETSI-ADSL-PE032m' '' sprintf('%.0fm ->',seglens(1))};
   {seglens(2)  'ETSI-ADSL-PE04m'  '' sprintf('%.0fm ->',seglens(2))};
   {seglens(3)  'ETSI-ADSL-PE09m'  'NT' sprintf('%.0fm ->',seglens(3))};
];
tt.traffic=[
    {1 4 'ADSL' nomodems};
];
ttlist=insertList(ttlist,tt);

%% ===========================================================================
%Loop #8 is the only test loop with bridge taps. The bridge taps
%put spectral nulls in the insertion loss and ripples in the line
%impedance. The impedance at the LT side is very low while the
%impedance at the NT side is close to 135Ohm. Testing with the line
%in the upstream direction will stress equipment more than testing
%in the downstream direction.
seglens=[len(8) 1100];
tt.name= sprintf('ETSI-ADSL-Loop8%s',namestr);             
tt.topology=[
   {0  '' 'CO' '' ...
         0 '' '' ''}; 
   {seglens(1) 'ETSI-ADSL-PE04m' ''   sprintf('%.0fm ->',seglens(1))...
         500 'ETSI-ADSL-PE04m' 'BT' '500m (ETSI-ADSL-PE04m)'};
   {seglens(2) 'ETSI-ADSL-PE04m' 'NT' sprintf('%.0fm ->',seglens(2))...
         500 'ETSI-ADSL-PE04m' 'BT' '500m (ETSI-ADSL-PE04m)'};
    ];
tt.traffic=[
    {1 3 'ADSL' nomodems};
    ];
ttlist=insertList(ttlist,tt);