Abstract: The base station apparatus compresses one-frame information of a broadcast channel to blocks of ½ of one frame or less and repeatedly sends this block in a one-frame time. The mobile station apparatus decodes the received signal in block units or added block units to carry out error detection. The mobile station apparatus receives and adds up the next block in the case that the error rate exceeds a threshold. The mobile station apparatus repeats this until the error rate falls below the threshold. When the error rate falls below the threshold, the mobile station apparatus stops reception of broadcast channel signals and uses the rest of time until a one-frame time elapses to monitor carrier information of a different mobile communication system for handover.

Abstract: The processing up to initial value setting in adaptive algorithm in a communication terminal apparatus is omitted by the use of a tap coefficient set by the adaptive algorithm in a base station as an initial value, and thereby the load of the calculation of equalization processing in the communication terminal apparatus is decreased, and the processing time of the equalization processing is shortened.

Abstract: Received quality detecting section 108 detects a received quality, bit determining section 111 determines whether a TPC bit is 0 or 1, amplitude reading section 112 reads a ratio of an amplitude of a signal other than the TPC bit and an amplitude of the TPC bit, accumulating section 113 determines an increase or decrease of transmit power and an amount of the increase and decrease of the transmit power using a symbol of the TPC bit for the increase or decrease, and an amplitude ratio for the amount of the increase and decrease to instruct to transmission amplifier 104, and multiplying section 114 multiplies the amplitude of the signal other than the TPC bit by a correction value corresponding to the received quality to determine the amplitude of the TPC bit.

Abstract: A peak power suppression apparatus and a peak power suppression method that reduce memory capacity and the amount of calculation while suppressing peak power in an OFDM signal. A frequency shift section (103) applies frequency shift to an OFDM signal generated in an IFFT section (102) in such a way that the frequency of a peak suppression carrier in this OFDM signal becomes 0. A direct current setup section (105) calculates a direct current signal that suppresses peak power in the frequency-shifted OFDM signal. An addition section (106) adds the direct current signal from the direct current setup section (105) to the frequency-shifted OFDM signal. A frequency shift section (111) applies to the OFDM signal to which the direct current signal has been added frequency shift in such a way that the frequency of the peak suppression carrier in this OFDM signal returns.

Abstract: The present invention has an object to provide a communication equipment, a communication method, a communication program, a recording medium, a mobile station, a base station, and a communication system, which are capable of assuring the quality of service.

Abstract: Converting section 201 converts I signal and Q signal in phase modulated signal of which delay wave distortion is cancelled into I′ signal and Q′ signal shown in I′-Q′ plane, respectively. Positive/negative decision section 202 outputs decoded bit in I′ signal as bit 3N+1. Positive/negative decision section 205 outputs an inversely rotated value by decoded bit in Q′ signal as bit 3N. Subtractor 206 outputs a decoded bit obtained by carrying out subtraction using the absolute value of I′ signal and absolute value of Q′ signal as bit 3N+2. Thus, it is possible to carry out decoding of phase modulated signal while keeping apparatus size and calculation amount.

Abstract: A coding section 101 performs error detection coding of data for each predetermined error detection unit, and an M-ary modulation section 102 arranges data belonging to a plurality of error detection units in one transmission unit, and transmits that data. A first decoding section 114 decodes a received signal, and performs error detection on the decoding result for each error detection unit. A second demodulation section 115 modifies the likelihood of each bit based on the result of error detection in the first decoding section 114. By this means, it is possible to improve the error correction capability of a signal that has undergone M-ary modulation using high-precision likelihoods, and to improve transmission quality.

Abstract: The present invention carries out transmission/reception of broadcast channels using only the last downlink slot of subframes using signals having a TDMA structure according to a CDMA/TDD system, and thus flexibly handles various services and avoids problems of interference in self-operated services in particular. The base station communication apparatus repeatedly transmits information contained in broadcast channels by the number of times corresponding to the time-sharing number and appropriately allots uplink and downlink slots, thus making the most of the features of uplink open-loop transmission power control and base station transmission diversity.

Abstract: In a receiving side apparatus 150, reception quality of receive data is measured by a reception quality measurement section 157, receive data errors are detected by an error detection section 156, and when an error is detected a retransmission request signal and reception quality signal are transmitted multiplexed with transmit data by a transmit frame creation section 158. In a transmitting side apparatus 100, when a retransmission request signal is received a capacity necessary for demodulating data in a receiving side apparatus 150 is detected from a reception quality signal by a scheduling section 110, and data is retransmitted at that capacity. By this means it is possible to reduce the number of data retransmissions during transmission and reception, and to improve transmission efficiency.

Abstract: Channel quality estimating section 104 estimates the channel quality from the reception signal quality and outputs the result to transmission method determining section 105 and control signal dividing section 108. Transmission method determining section 105 determines a transmission method of a signal transmitted to communication partner from channel conditions and outputs the result to switch 106, switch 107 and control signal dividing section 108. Control signal dividing section 108 divides the transmission method information into high-speed control signal which is transmitted periodically and low-speed control signal which is transmitted on demand rather than periodically. Moreover, control signal dividing section 108 determines the combinations of low-speed control signal and high-speed control signal outputted from a tendency of communication quality, and outputs the result to modulator 114.

Abstract: A small number of users who provide high interference in the other users, such as a user transmitting a high rate signal, are selected beforehand. First, a signal of the user is demodulated to generate a replica, and a difference between a received signal and the replica is calculated, thereby canceling the interference in signals of the other users, and further improving the system capacity.

Abstract: Signals subjected to orthogonal modulation with a plurality of carrier frequencies are added to detect peak power. Based on the peak power, a coefficient for suppressing an amplitude of a transmission baseband signal is calculated. Using the coefficient, the amplitude of a baseband signal to be inputted to a filter is suppressed. It is thereby possible to suppress the peak power assuredly, and by the effects of the filter, unnecessary frequencies are not generated.

Abstract: A transmitting apparatus 100 spreads broadcast information by means of a spreading section 103, limits the band of spread broadcast information by means of a band limiting filter section 104 so as not to overlap a guard frequency band, adds the output signal of a band limiting filter section 104 to transmit data after an inverse Fourier transform by means of an adding section 105, modulates the resulting signal by means of a modulation section 106, and transmits it. A receiving apparatus 150 passes only a signal in a guard frequency band by means of a reception filter section 154, demodulates it by means of a demodulation section 155, despreads it by means of a despreading section 156, and performs rake reception by means of a rake reception section 157 to obtain broadcast information. By this means, guard frequency bands can be used efficiently, and spectrum efficiency can be improved.

Abstract: Equipped with a plurality of mapping blocks 102 and 103 that carry out mappings of different rates, signals subjected to low-speed mapping are placed in the periphery of a band to which a plurality of sub-carriers are assigned at an interval corresponding to the symbol rate. The signal placed on the frequency axis in this way is converted to a time waveform through inverse Fourier transformation block 105, converted to a symbol time series through parallel/serial conversion block 106, then quadrature-modulated and transmitted.

Abstract: Wireless base station apparatus and communication terminal apparatus that perform wireless transmission with high capacity, without losing the real time aspect where several users engage in communication simultaneously. User A's and user B's transmit data are respectively sent to dedicated CH spreading sections 201 and 202 for spreading-modulation processing using codes #0 and #1. The spread-modulated data are each orthogonal-modulated in orthogonal modulating sections 204 and 205 and output to multiplexing section 207. User A's and user B's transmit data buffered in retransmit buffer 215 are sent to shared CH spreading section 203 for spreading-modulation processing using code #2. The spread-modulated data are orthogonal-modulated in orthogonal modulating section 206 and output to multiplexing section 207.

Abstract: P/S conversion section 302 performs parallel/serial conversion of data sequences #1 through #4 input in parallel, in accordance with control by assignment control section 303, so that data to a higher-priority communication terminal is assigned to an upper bit in one symbol; M-ary modulation section 304 performs M-ary modulation on the data that has been subject to parallel/serial conversion; S/P conversion section 305 converts a symbol that has been subject to M-ary modulation to parallel form; multipliers 306-1 through 306-4 execute spreading processing on the symbols output in parallel; multiplexing section 309 multiplexes the symbol that has been subject to spreading processing with an assignment notification signal that has been subject to spreading processing; and radio transmitting section 310 transmits the multiplex signal.

Abstract: A receiving apparatus that is equipped with a decoder that performs equalization and error correction simultaneously, as with a UDMV, for example, and enables burst errors to be corrected and demodulated data error rate characteristics to be improved even when there is fading that causes burst errors in a channel, and a transmitting apparatus that performs data transmission to this receiving apparatus. A transmitting apparatus 100 distributes transmit data to a plurality of carriers of difference frequencies and transmits the transmit data as a plurality of sequences differentiated by frequency. A receiving apparatus 150 performs maximal-ratio-combining of received signals in a combiner 153, performs equalization and Viterbi decoding simultaneously with a UDMV 154, and obtains demodulated data.

Abstract: Channel fluctuation estimating section 101 estimates fluctuation amount of the channel between transmitting apparatus 100 and receiving apparatus 200, and carrier number determining section 102 determines the number of subcarriers used in transmission of signal based on channel fluctuation amount. That is to say, in the case of a remarkably rapid channel fluctuation caused by fast fading, etc., carrier number determining section 102 deduces relatively the channel fluctuation between symbols or within a burst, by decreasing the subcarriers number and increasing symbol rate per one subcarrier.

Abstract: A training section 102 calculates a tap coefficient, an impulse response calculation section 103 calculates a impulse response of the tap coefficient, a tap selection section 104 selects a tap based on the size of the impulse response, and a replica generating section 105 generates a replica by multiplying a symbol for replica generation by the tap coefficient at the selected tap only. Also, the replica generating section 105 performs generation so as not to duplicate identical replicas in accordance with control by a control section 106.

Abstract: A channel estimation section 112 estimates the states of channels used for pieces of mobile station apparatus (A) and (B), using signals demodulated by radio processing sections 110, 111. A best SIR calculation section 118 calculates coefficients to be used for signal transformation by inverse matrix calculation, using the above channel estimation values by the above channel estimation section 112. A signal transformation section 119 performs linear transformation of transmission signals to the above pieces of mobile station apparatus, using the above coefficients from the above best SIR calculation section 118. Radio processing sections 120, 121 modulates each transmission signal after the above linear transformation for transmission through antennas 108, 109, respectively.