Inter-Frame Coding For Broadcast Communication

Abstract

A novel inter-frame coding approach to the problem of varying channel-state conditions in broadcast wireless communication is developed in this paper; this problem causes the appropriate code-rate to vary across different transmitted frames and different receivers as well. The main aspect of the proposed approach is that it incorporates an iterative rate-matching process into the decoding of the received set of frames, such that: throughout inter-frame decoding, the code-rate of each frame is progressively lowered to or below the appropriate value, prior to applying or re-applying conventional physical-layer channel decoding on it. This iterative rate-matching process is asymptotically analyzed in this paper. It is shown to be optimal, in the sense defined in the paper. Consequently, the data-rates achievable by the proposed scheme are derived. Overall, it is concluded that, compared to the existing solutions, inter-frame coding presents a better complexity versus data-rate tradeoff. In terms of complexity, the overhead of inter-frame decoding includes operations that are similar in type and scheduling to those employed in the relativelysimple iterative erasure decoding. In terms of data-rates, compared to the state-of-the-art two-stage scheme involving both error-correcting and erasure coding, inter-frame coding increases the data-rate by a factor that reaches up to 1.55×.H. Zeineddine and M. M. Mansour are with theand (1−x J ) dc < 1−x otherwise. In addition, X c converges to e −(1−µ) as J → ∞.From Lemma 4, it can be concluded that for an arbitrarily small γ, ∃J such that: X c < e −(1−µ)+γ ∀J > J .Therefore:(1 − x J ) dc < 1 − x ∀x > e −(1−µ)+γ and J > J .