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This letter focuses on the design of an adaptive Bit-Interleaved Coded Modulation (BICM) scheme for frequency selective slow fading channels where the transmitter has certain knowledge of the channel response. In particular, we consider the design of the interleaver stage for a specific convolutional code operating with OFDM modulation. The adaptive interleaver uses the puncturing tables of the Rate-Compatible Punctured Convolutional Codes (RCPC codes) to rearrange the bits as a function of the fading values and the specific constellation. The performance of different interleavers are compared, revealing that the adaptive RCPC-based interleaver produces larger Euclidean distances between the received codewords and reduces the packet error rate (PER), specially when the number of deep-faded subcarriers increases. Numerical results also evidence the importance of the interleaver choice when comparing the performance of different power allocation strategies. Index Terms--Adaptive interleaver, bit-interleaved coded modulation (BICM), channel state information at the transmitter (CSIT), orthogonal frequency-division multiplexing (OFDM), rate-compatible punctured convolutional codes (RCPC).

In this paper we design practical interleavers for regular, systematic repeat-accumulate (RA) codes. The new interleavers, which we call L-type and modified L-type interleavers, are deterministic, described by a single parameter, and straightforward to implement. Despite their simple description, the new interleavers are shown to perform equally as well as, or better than, traditional interleavers over a wide range of code lengths and rates. Index Terms--Interleavers, repeat-accumulate (RA) codes, sum-product algorithm, iterative decoding.