The optimum number of inserted known-bits in the rate matched turbo codes with known bits

The rate matched turbo codes were first proposed by DACOM Corp. for IMT-2000 in Korea. The main characteristic of the rate matched turbo codes with known bits is that some bits, which both encoder and decoder already know, are inserted in known positions between data before encoding and the inserted bits are deleted before transmitting. In those schemes, the number of inserted known-bits have an effect on the performance of system. In this paper, we derive the optimum number of inserted known-bits that result in the best performance for 64 kbit/s and 128 kbit/s data rates.