Blind detection for block coded interleaved division multiple access

In decentralized communication schemes such as ad-hoc networks, a major challenge concerns the synchronization and detection of users sending information simultaneously. Classical synchronisation techniques based on training sequences decrease dramatically the spectral efficiency and are rarely applicable in non-cooperative settings. In this contribution, we propose an efficient technique for blind detection in the context of block coded Interleaved Division Multiple Access (IDMA). Interestingly, without any additional dimension (space, time or frequency), the users can be fully separated when using low rate LDPC codes with the same interleavers (which is a new feature compared to classical IDMA schemes). Results, in the context of additive White Gaussian Noise (AWGN) and Rayleigh flat fading channels, demonstrate the potential of the method in the multi-user setting.