Abstract: The present invention provides an encoding apparatus, comprising means (21) for generating a checksum for incoming data, means (22) for constructing frames on the basis of said incoming data and said generated checksum, and means (23) for multidimensionally coding said frames. Further, the present invention comprises a decoding apparatus for iterative decoding of multidimensionally decoded information, comprising means (28) for performing at least one decoding iteration on multidimensionally coded information, and means (32) for checking the decoded information after each decoding iteration and for causing said decoding iteration means (28) to perform a further decoding iteration on the basis of a checking result. The present invention further comprises the corresponding encoding method and decoding method. The average processing delay and the computational complexity is significantly reduced, since only the required number of iteration steps is adaptively performed in the decoding apparatus.

Abstract: The present invention relates to a transmission method and a transmission apparatus for transmitting signals on the basis of a OFDM/TDMA-system, wherein a plurality of subcarriers being orthogonal to each other are allocated to a variable number of channels, each channel containing a variable number of subcarriers depending on information to be transmitted in said signals, wherein, for the transmission of said signals in a GSM-system having a constant number of predetermined GSM-frequency channels and a constant number of predetermined GSM-timeslots being grouped in GSM-frames, the number of said subcarriers is allocated corresponding to the bandwidth of said GSM-frequency channels, so that a multiple of one resulting OFDM/TDMA-timeslot matches with one or a multiple of one GSM-timeslots, wherein a pilot symbol is allocated to every n-th subcarrier in said GSM-frequency-channels, whereby n is an integer and>1, and wherein said signals are transmitted.

Abstract: A transmission technique for transmitting signals on the basis of an OFDM/TDMA-system, wherein a plurality of subcarriers that are orthogonal to each other are allocated to a variable number of channels, each channel containing a variable number of subcarriers depending On the information to be transmitted. For transmission in a GSM-system having a constant number of predetermined GSM-frequency channels and a constant number of predetermined GSM-timeslots being grouped in GSM-frames, the number of subcarriers allocated to each of the GSM-frequency channels is such that a multiple of the resulting OFDM/TDMA-timeslot matches with one (or a multiple of One) GSM-timeslot.

Abstract: A data modulation method and a data modulation device and a communication device are disclosed. The present invention relates to the synchronization and training preamble. The reference symbol optimized in order to contain the structure of “IA-A-IA-A-A-IA-A-IA-IA” is allocated to sub-carriers of the OFDM symbol. More specifically, by designing the structure of the preamble of the time domain, distinction from the other communication system can be certainly conducted holding the correctness of the clock synchronization. Also, we have adopted the series having low peak average ratio and dynamic range of sync symbol using the OFDM. Since the generation and the detection processings can be conducted in utilizing the generation device and the detection device of the sync preamble used in the convention system, this system has an advantage in increasing the common use of the LSI chip.