Reduction of Computation in TDM-FDM Transmultiplexer

The purpose of this correspondence is to point out that the computation required to convert FDM to TDM in [1] can be further reduced by a simple modification. The computation rates per channel are required to be 384 000 multiplications/s and 792 000 additions/s in [1]. After modification, those are reduced to 203 000 multiplications/s and 448 000 additions/s. In addition, about 300 words of storage can also be saved.