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-It is shown t h a t t h e capacity of t h e AWGN channel c a n be approached via a multilevel coding scheme w i t h t h e o u t p u t of each encoder m a p p e d i n t o a n i n d e p e n d e n t signal constellation. No active s h a p i n g is required in t h i s scheme, regardless of t h e signal-to-noise ratio. Moreover, shifted linear codes c a n be used.

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For a cellular communication network, the loss in up-link bandwidth-efficiency resulting from power equalization is considered. Here power equalization refers to the operation of adjusting the transmit power of mobile units in such a way that the received power is the same for all units whereas bandwidth-efficiency is measured in terms of sum-rate per cell divided by the total system bandwidth. A single-cell system is considered first, and the bandwidth efficiency is determined with and without power equalization as well as with and without shadowing. The analysis is then extended to multi-cell-systems. It is found that in all cases power equalization severely penalizes the bandwidth-efficiency.