High-order Modulation scheme based on combinational QPSK accelerators for HSPA Evolution in UE
15 April 2011
the UMTS Channel Unit Processor for 3GPP Base Station introduced earlier by Lucent technologies is an advanced 3G BTS baseband processor system that includes the QPSK Tx and couple of other key ASIC accelerators. Originally, the ASIC Tx accelerator targeted for supporting the WCDMA baseband transmission. This paper continues a deep study of the Channel Unit Processor ASIC Tx accelerator and extends it to UE (User equipment) and MTE transmitters by using the combinations of the basic QPSK structures to fully implement all the possible modulation schemes from BPSK, rotated QPSK, 4PAM, 16QAM, and 64QAM. At the end the paper gives out a general form of the combinational implementation for the higher order QAM (HOM) schemes.