The error control technology is applied to MPEG-2 TS packet with byte according to DVB criteria of digital television. One designed QPSK modulating and demodulating digital communication system can only be inputted and outputted serial digital data. When MPEG-2 TS packet with RS FEC via DVB SSI or PDH interface is transferred with this QPSK communication system

serial convolutional interweaver and de-interweaver must be designed according to DVB criteria. The design is implemented in FPGA. The experiment proves that the QPSK digital communication system performance is improved obviously when the convolutional interweaving is applied.