I am new to this site, which I joined with the aim of finding someone to help me with a little doubt.
I am trying to design a system that must be able to work at extremely low (the lower, the better, since that would improve the range) SNR (AWGN channel). Latency and datarate (less than 10Kbps at the source, low resolution imaging) are not a problem, so I am looking for the "best" FEC possible. It will use a BPSK with a roll-off factor of the RRC filter of 0,2.
As of now, the three options I am working with are Turbocodes, LDPC and BCH codes. The one I am considering implementing is an LDPC as outer code and a Turbocode as inner code, with an interleaver in between. However, I do not know whether this corresponds to the optimal configuration of outer and inner code.
For instance, the DVB-S2 standard makes use of a BCH code instead of the Turbo, while other spacial missions tend to use the latter.
Would any other combination of codes reduce the necessary Eb/No in order to achieve relatively low (<1e-04) BER?
How do these codes perform against burst errors? Apart from the interleaver between inner and outer code and a randomizer before the FEC stage, is there any other mechanism to improve this aspect?
What of the two (outer/inner) codes should have the highest coding rate and why?
Those are a lot of questions, but I would really appreciate if anyone could help in some way with any of them.
Thank you in advance