摘要:
The amount of information reported by a communication terminal apparatus to a communication control apparatus is reduced based on the congestion status of communication. Communication control 100 apparatus communicates with a communication terminal apparatus using frequency channels composed of two or more sub-channels defined by a predetermined frequency band includes: receiver 113 for receiving information data destined to the terminal apparatus; scheduler 113 for generating assignment information indicating the status of assignment of the received information data to each sub-channel; congestion information generator 103 for generating congestion information indicating the congestion degree of each sub-channel based on the generated assignment information; control information generator 104 for generating control information including the generated congestion information; and transmitter 111 for transmitting the generated control information to the terminal apparatus.
摘要:
Improving the accuracy of estimation of channel responses in receiving signals from a plurality of antennas is disclosed. A transmitting device of a base station includes a preamble A generating unit 010, a preamble B generating unit 011, phase rotating units 012 and 013, multiplexing units 014 and 015, an forward error correction coding unit 016, an S/P converting unit 017, a mapping unit 018, a changeover switch 019, IDFT (or IFFT) units 020 and 026, P/S converting units 021 and 027, GI (Guard Interval) inserting units 022 and 028, D/A converting units 023 and 029, radio transmitting units 024 and 030 and antenna units 025 and 031. In the preamble A generating unit 010 and the preamble B generating unit 011, a preamble A and a preamble B (see the packet format in Figure 1) are generated, respectively. The preamble A is outputted to the multiplexing units 014 and 015, while the preamble B is outputted to the phase rotating units 012 and 013. The phase rotating units 012 and 013 to which the preamble B has been inputted give continuous phase rotation to subcarriers of the preamble B. In the transmitting device of the base station according to this embodiment, the phase rotating unit 012 does not give phase rotation, but only the phase rotating unit 013 gives phase rotation to the preamble B.
摘要:
The invention provides precise estimation of a channel response and correct demodulation of an information signal even in the circumstance of being likely suffering interference. The invention includes an error correcting code unit 1, an S/P converting unit 2, a mapping unit 3, an IDFT (Inverse Discrete Fourier Transform) unit (IFFT: Inverse Fast Fourier Transform can be used) 4, a P/S converting unit 5, a GI (Guard Interval) inserting unit 6, preamble (A, B0, B1) storage selecting units 11-a and 11-b, switch units 12-a and 12-b, D/A converting units 13-a and 13-b, radio units 14-a and 14-b and antenna units 15-a and 15-b.
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:
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:
Each of first radio communication devices includes; a frequency spread unit which spreads frequency of a transmitted signal to generate a frequency-spread signal; and a mapping unit which allocates the frequency-spread signal to a subcarrier according to the mapping information which specifies a subcarrier. A second radio communication device includes: a demapping unit which extracts from a received signal a signal of the subcarrier specified by the mapping information; and an inverse frequency spread unit which inverse-frequency-spreads the extracted signal. The first radio communication device or the second radio communication device includes a use subcarrier decision unit that decides a subcarrier to which the frequency-spread-signal is allocated according to a communication path capacity of each subcarrier of each antenna used for transmission by the first radio communication devices and generates mapping information used to specify the decided subcarrier.
摘要:
A wireless communication system includes: a multiple number of mobile station apparatuses that transmit coded bits obtained by applying error-correction coding to information bits; a relay station apparatus that receives coded bits from the multiple mobile station apparatuses, applies network coding on the coded bits and transmits the network-coded bits; and a base station apparatus that receives and decodes the codedbits and the network-codedbits, wherein the base station apparatus, when decoding the received coded bits, performs iterative decoding by regarding the received coded bits as a serially concatenated code of network coding and error correction coding. Accordingly, decoding is performed by regarding the network code and the error correction code as a serial concatenated code, it is possible to obtain diversity with a simple configuration. Further, since no lamination is imposed on the error correction codingmethod, it is possible to provide a wireless communication system and the like which allow flexible system design.
摘要:
Improving the accuracy of estimation of channel responses in receiving signals from a plurality of antennas is disclosed. A transmitting device of a base station includes a preamble A generating unit 010, a preamble B generating unit 011, phase rotating units 012 and 013, multiplexing units 014 and 015, an forward error correction coding unit 016, an S/P converting unit 017, a mapping unit 018, a changeover switch 019, IDFT (or IFFT) units 020 and 026, P/S converting units 021 and 027, GI (Guard Interval) inserting units 022 and 028, D/A converting units 023 and 029, radio transmitting units 024 and 030 and antenna units 025 and 031. In the preamble A generating unit 010 and the preamble B generating unit 011, a preamble A and a preamble B (see the packet format in Figure 1) are generated, respectively. The preamble A is outputted to the multiplexing units 014 and 015, while the preamble B is outputted to the phase rotating units 012 and 013. The phase rotating units 012 and 013 to which the preamble B has been inputted give continuous phase rotation to subcarriers of the preamble B. In the transmitting device of the base station according to this embodiment, the phase rotating unit 012 does not give phase rotation, but only the phase rotating unit 013 gives phase rotation to the preamble B.
摘要:
A radio transmission device includes: a time-to-frequency converter that converts a time domain signal into a plurality of frequency signals; a subcarrier allocator that segments the plurality of frequency signals into a plurality of blocks, and allocates the plurality of frequency signals included in each of the plurality of blocks onto sequential subcarriers; a transmission power adjustor that adjusts a transmission power of a transmission signal including the plurality of subcarriers; and a controller that controls the subcarrier allocator and the transmission power adjustor so that the number of frequency signals included in one block increases as the transmission power increases.