Kochi University of Technology

Masanori Hamamura

Kazuki Chiba

Continuous-phase high compaction multicarrier-modulation (CPPC/HC-MCM) according to the present application uses a continuous phase modulation (CPM) technique to prevent an amplitude gap between two continuous signals, thereby improving characteristics of the conventional PC/HC-MCM in terms of effective use of a frequency bandwidth. The CPPC/HC-MCM can achieve a lower bit error rate (BER) for a wide signal-to-noise ratio at a common spectral efficiency of about 0.33 or less, as compared to the conventional unmodulated PC/HC-MCM.

Data transmission system and method

In a communication system adapted to MIMO transmission, a receiver may include a filter to filter signals received from a transmitter through the receiver antennas and having a weight matrix thereof updated by an adaptive algorithm with respect to each substream message symbol from the transmitter, and a code generator to feed back a part of the weight matrix updated by the filter, as an updated STF code, to the transmitter. The transmitter may make the transmission using the updated STF code which is optimized for a current channel state.

Communication apparatus, communication system, communication method and computer-readable storage medium

In a communication system including a plurality of pairs of a transmitting deviceand a receiving device, the transmission performance in the pairs is to be improved. The transmitting device-transmits a transmission signal s(t) to the receiving device-a plurality of number of times. The receiving device-updates the weight matrix Wand the hopping pattern Pused by the FIR filter which performs filtering on the transmission signal r(t) at a predetermined time interval. The receiving device-transmits the updated hopping pattern Pto the transmitting device-. The transmitting device-receives the hopping pattern Pto be used for subsequent spread spectrum.

Communication system and its method

Communication performance is to be improved in a communication system in which a plurality of wireless communication lines share space. A transmitting devicetransmits a transmission signal to a base stationa plurality of number of times. The base stationupdates a weight wto be used for an FIR filter, generates a hopping pattern Pto be used by the transmitting devicefor generating a transmission signal, adjusts the hopping pattern Pso as to suppress a peak-to-average ratio (PAR) occurring in the transmission signal to generate a hopping pattern P', quantizes the hopping pattern P&#x2032;, and transmits the quantized hopping pattern P&#x2032;to the transmitting device. The transmitting deviceuses the hopping pattern P&#x2032;received from the base stationin subsequent spread spectrum to generate a transmission signal.

A reception program maps, by PC mapping, the values of message data to symbol x, which describes the combinations of Mcarrier waves of Mcarrier waves with value-1 bits corresponding to the carrier waves to be transmitted, and receives the transmit signal created by performing transformation processing thereon to sample y. A matrix computing portion performs transformation processing on sample y' in a parallel form including an unnecessary signal component to symbol z&#x2032;. A first decoding portion sequentially performs maximum likelihood value decoding on groups of M bits of symbol z&#x2032; and finally decodes all of the symbol z&#x2032; to symbol x&#x2033;. If the symbol x&#x2033; includes Mvalue-1 bits, a second decoding portion handles the symbol x&#x2033; as the final decoding result and if not, the second decoding portion performs maximum likelihood decoding on the entire symbol z&#x2032; to obtain the final decoding result.

Growing community of inventors

Kochi, Japan

Masanori Hamamura