lut.m

OFDM降低峰平比采用预失真技术

% look-up-table renew function
function  [table_an,table_pn]=LUT(address_i,table_an,table_pn,table_indicate,in_ani,in_pni,out2_ani,out2_pni) % LUT: look up table function
a=10^-4;
b=8*10^-1;
cap=512;
table_an(address_i)=table_an(address_i)-a*((out2_ani/in_ani)-1);
table_pn(address_i)=table_pn(address_i)-b*(out2_pni-in_pni);
table_indicate(address_i)=0;
address_low=1;
address_high=cap;
for i=0:(address_i-1)
    table_indicate_addressi=table_indicate(address_i-i);
    if(table_indicate_addressi==1)
       address_low=(address_i-i);
        break;
    else
        address_low=1;
    end
end 
for i=(address_i):cap
    table_indicate_i=table_indicate(i);
   if(table_indicate_i==1)
        address_high=i;
        break;
    else
        address_high=cap;
    end
end 
table_indicate(address_i)=1;
[table_an,table_pn]=insert(table_an,table_pn,address_i,address_low,address_high); % linear interpolation