Using powerful “turbo” codes for 14.4 kbit/s data service in GSM or PCS systems

The current maximum user data rate in GSM is 9.6 kbit/s per time slot. To increase the rate to 14.4 kbit/s by puncturing the code bits which are generated by the same convolutional coding scheme used for GSM 12.0 kbit/s, may result in a loss of about 2 dB and is not practicable in many situations. In this paper, a scheme based on “turbo” codes is introduced for the GSM 14.4 kbit/s data service. Our study indicates that the new approach can achieve almost the same performance as the GSM 12.0 kbit/s standard. Contrary to the common belief we have shown that the complexity increases less, if a new decoding algorithm for high code rates is used. Furthermore, this new coding scheme can be implemented in a currently available DSP for mobile communication