摘要:
Error detection section 109 carries out error detection using demodulated data and outputs an error rate to SIR versus error rate estimation section 110. SIR versus error rate estimation section 110 estimates an SIR versus error rate and outputs the result of decision as to whether the correction of the target SIR value is necessary or not to target SIR correction section 111. Target SIR correction section 111 corrects the target SIR value based on the decision result. The information on the demodulation capability of a BTS is output to G parameter control section 112 and G parameter control section 112 determines an optimal gain factor. A G parameter indicating the determined gain factor is output to multiplexing section 107 of the BTS. The G parameter is output to SIR versus error rate estimation section 110. This makes it possible to perform communications with an optimal gain factor and target SIR during diversity handover between base stations with and without an interference canceller or between base stations with interference cancellers of different capabilities.
摘要:
An allocation section 101 in a base station apparatus of the present invention sets the transmission rate of a transmit signal for a communication terminal apparatus based on a DRC signal transmitted from that communication terminal apparatus. A power margin information detector 117 detects power margin information from a demodulated signal generated by a demodulator 115, and, using that power margin information, a power setting section 118 makes a setting so as to give the minimum transmission power value at which received signal characteristics in each communication terminal apparatus meet the desired quality. Using the set transmission power value, the base station apparatus transmits a transmit signal of the set transmission rate to a communication terminal apparatus. By this means it is possible to suppress interference to a communication terminal apparatus that performs adaptive modulation communication with another base station apparatus and a communication terminal apparatus that performs adaptive modulation communication with the local base station apparatus at the same time.
摘要:
A retransmission request signal creation section (119) outputs an ACK signal or NACK signal to a NACK signal counting section (120) based on the result of error detection by an error detection section (118), the NACK signal counting section (120) counts, for each communication mode, the number of NACK signals output (that is, the number of data retransmissions) before an ACK signal is output from the retransmission request signal creation section (119), and a table rewriting section (121) compares the number of retransmissions counted by the NACK signal counting section (120) with a predetermined threshold value for the number of retransmissions, and rewrites the contents of a communication mode table (102) based on the result of this comparison.
摘要:
PL demodulation section 203 demodulates pilot signals of a received signal. SIR detection section 205 detects the reception quality of the demodulated pilot signals. fd detection section 206 detects a Doppler frequency using the demodulated pilot signals. Requested modulation method deciding section 207 decides a modulation method to be requested to the base station using the reception quality of pilot signals and the detected Doppler frequency. Command generation section 208 generates a command corresponding to the decided modulation method. Adaptive demodulation section 204 performs demodulation processing on the received signal using the demodulation method corresponding to the modulation method decided by requested modulation method deciding section 207. This makes it possible to maintain good reception quality even in a fading environment.
摘要:
Desired signal power detection sections 109 to 116 measure a signal power level from a communication partner received at respective antennas 101 to 108. Antenna set selection section 117 obtains a sum of signal power levels from the communication partner received at four antennas belonging to each of antenna sets A to D each composed of combined antennas selected in advance to form a predetermined radiation pattern, for each antenna set, and selects an antenna set with the sum being the highest. Switch 120 connects received signals only from antennas belonging to the selected antenna set to reception RF sections 121 to 124. Received signal inputted to respective reception RF sections 121 to 124 are converted into respective intermediate-frequency signals, combined in signal combining section 125, and demodulated in demodulation section 126 to be a desired signal.
摘要:
The reception electric field strength of a desired wave is detected by desired wave reception electric field strength detecting means 102, the reception electric field strength of an interference wave is detected by interference wave reception electric field strength detecting means 103, and they are compared with each by comparing means 104 so as to calculate a D/U ratio. Also, an FER is detected by frame error rate detecting means 106. Future D/U ratio and FER are predicted from both histories and the switching of a communication channel is performed, whereby a reception state is detected without interrupting communications, and a communication quality is improved.
摘要:
A mobile communication system which is capable of, when carrying out mobile communication using a shared channel, increasing in efficiency of transmission timing of the data transmission rate request value to prevent wasteful power consumption and hence reduce power consumption. A mobile station apparatus of the mobile communication system measures CIR of the received signal from a base station apparatus at a CIR measuring section, and decides the data transmission rate request value corresponding to the measured CIR value at a rate request value deciding section. Also, it detects an error of the received signal at a CRC section, and, when no error is found, calculates a difference between the average data transmission rate from a base station apparatus and the data transmission request value at a rate request value transmission controlling section. Then, it transmits the data transmission rate request value to the base station apparatus only when the obtained difference is larger than a threshold value.
摘要:
Provided is a wireless communication device which can improve the notification accuracy of the channel state information (CSI) without straining the feedback circuit. In this device, a channel estimator (105) uses a pilot signal input from a wireless receiver (102) to estimate the channel and obtain a plurality of path gains in each of a plurality of delay periods. Then, the channel estimator (105) outputs the plurality of path gains to a quantizer (107). The quantizer (107) quantizes the plurality of path gains in the number of notification bits corresponding to each of the plurality of delay periods based on the correspondence of the delay period and the number of notification bits input from a setting unit (106).
摘要:
Provided is a mobile communication system which includes a plurality of RAT (Radio Access Technology) and can eliminate the need of a control channel for reporting RAT information so as to prevent congestion or shortage of the control channel capacity. In the mobile communication system, an LTE relay station (30) has a cover area (31) identical to a cover area (21) owned by a WLAN host station (20) and relays/transmits the signal received from an LTE base station (10) to a mobile station (40) in the cover area (31). The LTE relay station (30) adds to the signal received from the LTE base station (10), one of the offsets: a frequency offset, a time offset, and a power offset as information indicating that the mobile station (40) which receives a relay signal from the local station is located in the cover area (21) of WLAN and transmits the signal after offset addition to the mobile station (40) located in the cover area (31) (i.e., the cover area (21)).
摘要:
A spatial multiplex number controlling method and others wherein streams can be separated for each of receivers and the transmission efficiency can be improved. In a receiving apparatus, a PER is calculated from a history of CRC test results per stream multiplex number. A reception quality and an offset corresponding to the calculated PER are fed hack to a transmitting apparatus. The transmitting apparatus assigns, based on the fed-back reception quality and offset, the streams, thereby controlling the stream multiplex number.