Abstract:
A radio transmission apparatus performs communications with high transmission efficiency. In this apparatus, a modulator modulates data and outputs to a first spreader. A second modulator modulates data under a modulation scheme having a higher M-ary number than the first modulator and outputs the modulated data to a second spreader. The first spreader spreads the data and outputs the spread data to a frequency domain mapping section. The second spreader spreads the data and outputs the spread data to a time domain mapping section. A frequency domain mapping section maps chips with spread data on subcarriers in the frequency domain and outputs the data with chips mapped on subcarriers to an IFFT section. The time domain mapping section maps chips with spread data on subcarriers in the time domain and outputs the data with chips mapped on subcarriers to the IFFT section.
Abstract:
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)).
Abstract:
Provided is a base station capable of suppressing increase of overhead of allocation result report in frequency scheduling in multi-carrier communication and obtaining a sufficient frequency diversity effect. In the base station, encoding units (101-1 to 101-n) encode data (#1 to #n) to mobile stations (#1 to #n), modulation units (102-1 to 102-n) modulate the encoded data so as to generate a data symbol, a scheduler (103) performs frequency scheduling according to a CQI from each mobile station so as to uniformly allocate data to the respective mobile stations for a part of RB extracted from a plurality of RB, and an SCCH generation unit (105) generates control information (SCCH information) to report the allocation result in the scheduler (103) to the respective mobile stations.
Abstract:
Data streams stored in buffers are modulated by modulation sections. Multipliers multiply the signals output from the modulation sections by weights output from a weight control section. The signals output from the multipliers are added up by addition sections, subjected to radio transmission processing by transmission radio sections and sent through antennas. A buffer control section controls the buffers based on a retransmission count output from a retransmission count detection section. The weight control section outputs weights different from weights at the time of previous transmission to the multipliers every time data is retransmitted. This allows a diversity gain at the time of data retransmission to be increased even if a time variation of the propagation path environment for radio signals is slow.
Abstract:
A base station apparatus is provided, which includes a generator configured to generate a synchronization signal and a transmitter configured to transmit the generated synchronization signal. The generator is configured to generate a synchronization signal to be mapped on a subcarrier included in one of a plurality of frequency resource candidates that are separated by an interval, which is a common multiple of a determined frequency spacing and a subcarrier spacing between contiguous subcarriers, wherein the subcarrier spacing does not have a value that is a divisor of the determined frequency spacing.
Abstract:
There is provided a wireless communication relay station apparatus and a wireless communication base station apparatus capable of allocating resources dynamically to each apparatus in accordance with traffic. A wireless communication relay station apparatus according to the invention includes a receiver that receives data from the wireless communication base station apparatus or the wireless communication mobile station apparatus, and a selector that selects data, within an uplink subframe or a downlink subframe, from: first data to be relayed from the own apparatus to the wireless communication base station apparatus; second data to be relayed from the own apparatus to the wireless communication mobile station apparatus; third data to be relayed from the wireless communication base station apparatus to the own apparatus; and fourth data to be relayed from the wireless communication mobile station apparatus to the own apparatus. The receiver receives allocation information for switching transmission/reception in the own apparatus from the wireless communication mobile station apparatus within an uplink subframe or a downlink subframe. The selector switches the first data and the fourth data within the uplink subframe in accordance with the allocation information received by the receiver, or the selector switches the second data and the third data within the downlink subframe in accordance with the allocation information received by the receiver.
Abstract:
A wireless transmission apparatus that can accurately select an optimal modulation scheme on a per block basis in a multi-carrier communication system in which block division of subcarriers and adaptive modulation are performed. In this wireless transmission apparatus, a propagation path characteristics acquisition section acquires the average SNR and SNR variance for each block, which are estimated by a wireless reception apparatus, using received signals inputted from a reception RF section and outputs these to an assignment section. The assignment section selects a modulation scheme for each block based on the average SNR and SNR variance of each block inputted from the propagation path characteristics acquisition section and modulation sections modulate multi-carrier signals included in each block, with the modulation scheme for each block selected by the assignment section.
Abstract:
Provided is a base station capable of performing cell search of all mobile stations having different communicable frequency band widths in a scalable band width communication system to which a multi-carrier communication method such as the OFDM method is applied. The base station includes: a modulation unit (102) for modulating SCH data after being encoded; a sub carrier setting unit (105) for setting one of the sub carriers to a sub carrier (SCH sub carrier) constituting the OFDM symbol for SCH data transmission; and an IFFT unit (106) for mapping the SCH data to the sub carrier set by the sub carrier setting unit (105) among the sub carriers and performing IFFT to generate an OFDM symbol. The sub carrier setting unit (105) sets one of the sub carriers which has a frequency of a common multiple between the sub carrier interval and the cell search interval as an SCH sub carrier.
Abstract:
Provided is a base station capable of performing cell search of all mobile stations having different communicable frequency band widths in a scalable band width communication system to which a multi-carrier communication method such as the OFDM method is applied. The base station includes: a modulation unit (102) for modulating SCH data after being encoded; a sub carrier setting unit (105) for setting one of the sub carriers to a sub carrier (SCH sub carrier) constituting the OFDM symbol for SCH data transmission; and an IFFT unit (106) for mapping the SCH data to the sub carrier set by the sub carrier setting unit (105) among the sub carriers and performing IFFT to generate an OFDM symbol. The sub carrier setting unit (105) sets one of the sub carriers which has a frequency of a common multiple between the sub carrier interval and the cell search interval as an SCH sub carrier.
Abstract:
A radio transmitting apparatus wherein even if a preamble sequence transmitted via any one of the antennas of the radio transmitting apparatus is detected, the order of the space diversity can be determined with reliability and data signals can be normally decoded. In this apparatus, a deciding unit (101) decides preamble sequences the number of which is equal to the order of the space diversity and further decides transmission block intervals the number of which is equal to or greater than the order of the space diversity. An allocating unit (102) sequentially allocates the preamble sequences, the number of which is equal to the order of the space diversity, to the respective antennas, the number of which is equal to the order of the space diversity, within the respective transmission block intervals. The allocating unit (102) allocates different ones of the preamble sequences to the respective antennas at the respective same transmission timings that are within the respective transmission block intervals.