I am trying to implement the LDPC code for OFDM system, where I input data should be binary of length $1024$ and the output coded data of length $2048$ (means of rate 1/2).
As known in Matlab integrated function, we build the encoder and decoder, respectively, as:
ldpcEncoder = comm.LDPCEncoder; %Encoder ldpcDecoder = comm.LDPCDecoder; %Decoder
After checking that, I see that parity check matrix is set by default into $32400$ x $64800$ which means the input data length must be a column of length $32400$.
I need the input data to be set manually, for example of length $1024$, how can I modify the parity check of the above encoder?