Abstract: Provided is a transmission device which improves the error rate characteristic upon decoding when performing error correction encoding by using a self-orthogonal code or an LDPC-CC in a communication system using a communication path having a fading fluctuation, multi-value modulation, or MIMO transmission. In the transmission device, the self-orthogonal encoding unit (110) encodes a self-orthogonal code having a constriction length K and an interleave unit (130) rearranges a code word sequence so that the same modulation symbol includes an information bit of a moment i and a non-correlated bit of the information bit of the moment i in a multi-value modulation unit (150).

Abstract: Provided is a transmission device which improves the error rate characteristic upon decoding when performing error correction encoding by using a self-orthogonal code or an LDPC-CC in a communication system using a communication path having a fading fluctuation, multi-value modulation, or MIMO transmission. In the transmission device, the self-orthogonal encoding unit (110) encodes a self-orthogonal code having a constriction length K and an interleave unit (130) rearranges a code word sequence so that the same modulation symbol includes an information bit of a moment i and a non-correlated bit of the information bit of the moment i in a multi-value modulation unit (150).

Abstract: It is possible to provide a transmission control method, a radio communication system, and a radio base station device which can reduce the time required until an inter-cell interference is reduced so as to improve the system throughput. A base station (200) includes: an FFT unit (210) which receives an interference report transmitted by using a common radio resource common to adjacent cells from a plurality of radio terminals (100) existing in different adjacent cells; and an adaptive FFR processing unit (230) which controls adaptive FFR processing in a downstream line of the local cell according to the reception interference report. Thus, by receiving an interference report directly from the radio terminals (100) existing in adjacent cells, it is possible to modify the transmission mode by considering the interference state in the adjacent cells. This eliminates the need of sending a report on a transmission mode modification which has been conventionally sent between adjacent base stations (200).

Abstract: An encoding method by which an encoding speed is improved is disclosed. An encoder (100) comprises an input data storage section (107) for outputting the stored input data (D100) according to an output control signal (108), an input data count section (101) for counting the inputs of input data (D100), an output control section (102) for controlling the output destination of the input data (D100) according to the input counts, one-bit storage sections (103-1 to 103-(N?K)) for holding one-bit data, row-vector storage sections (104-1 to 104-K) for holding row vectors of an LDPC code creation matrix, vector multiplying sections (105-1 to 105-K) for multiplying a row vector and a column vector, a parity storage section (109) for holding a parity created by the multiplication, and an LDPC code-word series creating section (106); for creating an LDPC code word from the input data series and parity series and outputting it.

Abstract: When the SC-FDMA method is used in combination with the multi-antenna transmission technique, a radio transmission method effectively improves the frequency use efficiency by performing appropriate frequency allocation to a plurality of antennas while suppressing degradation of the reception quality caused by interference. In the radio transmission method of the SC-FDMA type, according to the number of terminals simultaneously accessing a base station within a usable frequency band, it is possible to allocate all the transmission signals (transmission stream) to be transmitted by different antennas to different frequency bands or to use the MIMO transmission in combination. Moreover, according to the number of terminals making an access, the number of terminals which perform the MIMO transmission can be varied.

Abstract: Provided is a multi-antenna transmission device (400) which can perform MLD by using a simple configuration of a reception device in a MIMO-AMC system. The multi-antenna transmission device (400) includes common signal point mapping units (401, 402) for mapping data transmitted from different antennas (111, 112) in transmission scheme using MIMO spatial multiplexing, to common signal points shared by respective modulation methods. Thus, the arrangement of baseband signal points obtained by mapping a code word after channel encoding onto an IQ plane can be shared as common signal points shared by modulation methods. Accordingly, the reception device need not prepare a particular circuit for performing MLD calculation in accordance with a combination of the methods for modulating the signals which have been MIMO-space multiplexed. This can reduce the circuit size of the MLD calculation circuit.