摘要:
To provide a system that can accommodate a greater number of terminals within a limited band and can obtain a higher transmission rate. While the number of frequency signals (spectrums) output in parallel by performing a spread spectrum from the DFT unit of each terminal is 12, the number of sub-carriers constituting one sub-channel is set at 10 or 11. In this case, the users (users A and G) allocated to the sub-channels at both ends of the band will not perform transmission of one frequency signal at the end (one sub-carrier) of all the frequency signals output from the DFT unit, whereas the users (users B to F) allocated to the other sub-channels will not perform transmission of the frequency signals at the ends (two sub-carriers). This transmission can be realized by deleting (clipping) the associated number of signals from both ends or from one end of the frequency signals output from the DFT unit of each terminal and allocating the frequency signals after clipping, to individual sub-channels.
摘要:
By controlling to select encoding appropriately considering characteristics of equalization and decoding of a receiving apparatus employing a turbo equalization technology, it is possible to attain a high transmission characteristic. Information bits of two systems including a sequence which is input to a first RSC encoding unit 22 and a sequence which is input through an interleaving unit 21 to a second RSC encoding unit 23 are set for input information bits, and each of which is subjected to RSC encoding. Each encoded parity bit is input to a puncturing unit 24. Since a systematic bit obtained by the first RSC encoding unit 22 is the information bit itself, a systematic bit obtained by the second RSC encoding unit 23 is not transmitted. In the puncturing unit 24, while puncturing is applied according to a predetermined coding rate, selection of either an RSC code or a turbo code is carried out by a puncturing control unit 25.
摘要:
A clipping rate is controlled in spectrum shaping according to a propagation path to thereby improve transmission characteristics and perform communication at a stable transmission rate.Propagation path characteristics are detected by a propagation path information detection unit 5 for detecting propagation path information fed back from a base station device and a water filling principle for distributing energy by a primary spectrum shaping unit 6 according to the propagation path characteristics is applied to transmission spectrum obtained by a DFT unit 4. Clipping information in secondary spectrum shaping fed back from the base station device is detected by a clipping information detection unit 7 to perform the secondary spectrum shaping by a secondary spectrum shaping unit 8. At this time, with the clipping rate by the secondary spectrum shaping unit 8, clipping rates of all transmission devices multiplexed in a scheduling unit 26 of the base station device are controlled adaptively.
摘要:
A clipping rate is controlled in spectrum shaping according to a propagation path to thereby improve transmission characteristics and perform communication at a stable transmission rate.Propagation path characteristics are detected by a propagation path information detection unit 5 for detecting propagation path information fed back from a base station device and a water filling principle for distributing energy by a primary spectrum shaping unit 6 according to the propagation path characteristics is applied to transmission spectrum obtained by a DFT unit 4. Clipping information in secondary spectrum shaping fed back from the base station device is detected by a clipping information detection unit 7 to perform the secondary spectrum shaping by a secondary spectrum shaping unit 8. At this time, with the clipping rate by the secondary spectrum shaping unit 8, clipping rates of all transmission devices multiplexed in a scheduling unit 26 of the base station device are controlled adaptively.
摘要:
To perform control so as to achieve a transmission power that satisfies a desired communication quality by an access method which a mobile station apparatus uses, in consideration of the frequency-selective diversity effect, when switching an access method to the one having a different frequency-selective diversity effect. In a wireless communication system in which a communication control apparatus and a communication terminal apparatus that are able to use a plurality of types of access methods perform wireless communication using any of the access methods, the communication control apparatus, when the necessity of changing the access method arises, determines the access method after change and notifies the communication terminal apparatus of switching the access method before change to the determined access method, and performs the transmission power control in accordance with communication characteristics of the determined access method.
摘要:
An encoding unit encodes an information bit sequence. An IDFT unit generates a spectrum from the signals of the information bit sequence. A clipping unit generates, when re-transmitting the information bit sequence, a transmission spectrum that differs from that of the previous transmission. An OFDM signal generation unit transmits the transmission spectrum.
摘要:
A mobile station apparatus includes a plurality of PAs (Power Amplifiers) and a plurality of antennas and transmission performances thereof is to be improved when transmission signals having peak powers different from one another are transmitted through the use of the respective antennas. A transmission apparatus includes a plurality of PAs and a plurality of antennas and transmits a signal having a high peak power, by means of determining a transmission signal to be transmitted through the use of each of the PAs based on the capability of each of the PAs, converting the transmission signal into a frequency signal by time-frequency conversion, dividing the frequency signal into a plurality of clusters, and allocating the clusters to bands non-contiguously. Furthermore, the transmission apparatus transmits a signal having a low peak power by means of allocating the frequency signal to continuous bands.
摘要:
The present invention reduces the amount of frequency resources required for uplink cooperative communication. There is provided a base station device that is applied to a communication system in which a plurality of base station devices establish cooperative communication with at least one mobile station device and includes a base station-to-base station communication section 220 and a control information determination section 216. The base station-to-base station communication section 220 communicates with another base station device when establishing cooperative communication. The control information determination section 216 allocates a band for communication use by the mobile station device in such a manner that a signal received cooperatively by another base station device and a signal received uncooperatively by another base station device overlap with each other at certain frequencies.
摘要:
According to the present invention, a transmitter includes: multiple antennas 15-1, 15-2; a DFT unit 04 configured to transform a time domain signal into a frequency domain signal; a cluster mapping unit 05 configured to divide the frequency domain signal into clusters and to assign the clusters to frequencies on the basis of cluster assignment information; an IDFT unit 06 configured to transform a mapped frequency domain signal into a time domain signal; and cyclic delay setting units 11-1, 11-2 configured to set, for the respective multiple antennas, a cyclic delay amount to the IDFT-transformed time domain signal.
摘要:
A wireless communication system which includes a base station and a mobile station and in which the mobile station performs data transmission to the base station by allocating a transmission signal converted into a frequency signal to contiguous frequency bands or non-contiguous frequency bands divided into a predetermined number, wherein, when retransmission occurs in the data transmission the mobile station has performed by allocating the transmission signal converted into the frequency signal into the non-contiguous frequency bands, the base station determines a transmission power headroom of the mobile station in the allocation of the transmission signal to the non-contiguous frequency bands, and, if a result of the determination shows that there is not a transmission power headroom, the base station instructs the mobile station to allocate the transmission signal to the contiguous frequency bands and to perform the retransmission by increasing transmission power.