of a sub channel repeater according to a first embodiment of the present invention referring to fig9 input data blocks b 1 b 2 b 3 b 4 900 are provided to a sub channel repeater 911 the sub channel repeater 911 repeats each of the input data blocks b 1 b 2 b 3 b 4 900 over 4 sub channels further reference numerals 913 of u 1 to u 16 represent sub channels thus as illustrated in fig9 the input data block b 1 is repeated over the sub channels u 1 u 5 u 9 and u 13 and the input data block b 2 is repeated over the sub channels u 2 u 6 u 10 and u 14 further the input data block b 3 is repeated over the sub channels u 3 u 7 u 11 and u 15 and the input data block b 4 is repeated over the sub channels u 4 u 8 u 12 and u 16 as a result the received input data blocks 900 are subject to sub channel repetition by the sub channel repeater 911 and thus converted to 16 sub channel data blocks u 1 u 2 u 16 913 then the sub channel data blocks u 1 u 2 u 16 913 are provided to associated mappers 915 where the provided sub channel data blocks are subject to mapping for modulation fig9 shows an example where 4 input data blocks are repeated over 4 sub channels and the repeated sub channel data blocks are mapped in their own unique mappers however fig1 shows an example where the sub channel data blocks are mapped.