WIRELESS BASE STATION APPARATUS AND MOBILE WIRELESS TERMINAL APPARATUS
In the downlink, the channel band at each end of three 20-MHz channel bands has the DC subcarrier at its center at a position spaced apart from the DC subcarrier of the middle channel band by 18.015 MHz or more and, more specifically, by 18.3 MHz corresponding to a spacing of 300 kHz that is the least common multiple of the 100-kHz channel raster and the 15-kHz subcarrier spacing. The subcarriers at the two ends are rearranged between the channel bands.
1 . A wireless base station apparatus which wirelessly communicates with a plurality of mobile wireless terminal apparatuses via channel bands including a plurality of subcarriers, comprising:
a detection unit which detects a communication capability from data received from a mobile wireless terminal apparatus;
a channel assigning unit which selectively assigns, to the mobile wireless terminal apparatus, one or three of a first channel band, a second channel band, and a third channel band in accordance with a detection result of the detection unit; and
a wireless transmission unit which performs wireless transmission to the mobile wireless terminal apparatus via the channel band assigned by the channel assigning unit,
wherein the first channel band is arranged so as to locate a DC subcarrier on a channel raster,
the second channel band is arranged so as to be adjacent to the first channel band from a high frequency side and locate a DC subcarrier on the channel raster while arranging subcarriers in number asymmetrical with respect to the DC subcarrier, and
the third channel band is arranged so as to be adjacent to the first channel band from a low frequency side and locate a DC subcarrier on the channel raster while arranging subcarriers in number asymmetrical with respect to the DC subcarrier.
2 . The apparatus according to claim 1 , wherein each of the second channel band and the third channel band makes the subcarriers asymmetrical by assigning a larger number of subcarriers on a side of the DC subcarrier close to the first channel band.
3 . The apparatus according to claim 1 , wherein each of the second channel band and the third channel band makes the subcarriers asymmetrical by assigning a larger number of subcarriers on a side of the DC subcarrier far from the first channel band.
4 . The apparatus according to claim 1 , wherein the number of subcarriers of the first channel band, the number of subcarriers of the second channel band, and the number of subcarriers of the third channel band are equal.
5 . The apparatus according to claim 1 , wherein the number of subcarriers of the second channel band and the number of subcarriers of the third channel band are different from the number of subcarriers of the first channel band.
6 . The apparatus according to claim 1 , wherein subcarriers are arranged at positions of the DC subcarriers of the second channel band and the third channel band.
7 . A wireless base station apparatus which wirelessly communicates with a plurality of mobile wireless terminal apparatuses via channel bands including a plurality of subcarriers, comprising:
a detection unit which detects a communication capability from data received from a mobile wireless terminal apparatus;
a channel assigning unit which selectively assigns, to the mobile wireless terminal apparatus, at least one of a first channel band and a second channel band in accordance with a detection result of the detection unit; and
a wireless transmission unit which performs wireless transmission to the mobile wireless terminal apparatus via the channel band assigned by the channel assigning unit,
wherein the first channel band is arranged so as to locate a DC subcarrier on a channel raster, and
the second channel band is arranged so as to be adjacent to the first channel band and locate a DC subcarrier on the channel raster while arranging subcarriers in number asymmetrical with respect to the DC subcarrier.
8 . The apparatus according to claim 7 , wherein the second channel band makes the subcarriers asymmetrical by assigning a larger number of subcarriers on a side of the DC subcarrier close to the first channel band.
9 . The apparatus according to claim 7 , wherein the second channel band makes the subcarriers asymmetrical by assigning a larger number of subcarriers on a side of the DC subcarrier far from the first channel band.
10 . The apparatus according to claim 7 , wherein the number of subcarriers of the first channel band and the number of subcarriers of the second channel band are equal.
11 . The apparatus according to claim 7 , wherein the number of subcarriers of the second channel band is different from the number of subcarriers of the first channel band.
12 . The apparatus according to claim 7 , wherein a subcarrier is arranged at a position of the DC subcarrier of the second channel band.
13 . The apparatus according to claim 1 , further comprising a division unit which divides the channel band assigned by the channel assigning unit into a plurality of resource blocks by putting, from an end of the channel band, every preset number of subcarriers included the channel band together into a resource block.
14 . The apparatus according to claim 7 , further comprising a division unit which divides the channel band assigned by the channel assigning unit into a plurality of resource blocks by putting, from an end of the channel band, every preset number of subcarriers included the channel band together into a resource block.
15 . The apparatus according to claim 13 , further comprising a channel arranging unit which, when transmitting an initial synchronization channel to be used for initial synchronization in a band to transmit a resource block including the DC subcarrier out of the resource blocks divided by the division unit, arranges the initial synchronization channel symmetrically with respect to the DC subcarrier.
16 . The apparatus according to claim 14 , further comprising a channel arranging unit which, when transmitting an initial synchronization channel to be used for initial synchronization in a band to transmit a resource block including the DC subcarrier out of the resource blocks divided by the division unit, arranges the initial synchronization channel symmetrically with respect to the DC subcarrier.
17 . A mobile wireless terminal apparatus which performs wireless communication using a channel band including a plurality of subcarriers and assigned by a wireless base station apparatus, comprising:
a detection unit which detects the assigned channel band from data received from the wireless base station apparatus; and
a wireless reception unit which receives a radio signal transmitted from the wireless base station apparatus via one or three of a first channel band, a second channel band, and a third channel band in accordance with a detection result of the detection unit,
wherein the first channel band is arranged so as to locate a DC subcarrier on a channel raster,
the second channel band is arranged on a frequency side higher than the first channel band so as locate a DC subcarrier on the channel raster while arranging subcarriers in number asymmetrical with respect to the DC subcarrier, and
the third channel band is arranged on a frequency side lower than the first channel band so as to locate a DC subcarrier on the channel raster while arranging subcarriers in number asymmetrical with respect to the DC subcarrier.
18 . A mobile wireless terminal apparatus which performs wireless communication using a channel band including a plurality of subcarriers and assigned by a wireless base station apparatus, comprising:
a detection unit which detects the assigned channel band from data received from the wireless base station apparatus; and
a wireless reception unit which receives a radio signal transmitted from the wireless base station apparatus via at least one of a first channel band and a second channel band in accordance with a detection result of the detection unit,
wherein the first channel band is arranged so as to locate a DC subcarrier on a channel raster, and
the second channel band is arranged so as to be adjacent to the first channel band and locate a DC subcarrier on the channel raster while arranging subcarriers in number asymmetrical with respect to the DC subcarrier.
19 . The apparatus according to claim 17 , wherein the channel band to be received by the wireless reception unit is divided into a plurality of resource blocks by putting, from an end of the channel band, every preset number of subcarriers included the channel band together into a resource block.
20 . The apparatus according to claim 18 , wherein the channel band to be received by the wireless reception unit is divided into a plurality of resource blocks by putting, from an end of the channel band, every preset number of subcarriers included the channel hand together into a resource block.
21 . The apparatus according to claim 19 , wherein in a band to receive a resource block including the DC subcarrier out of the resource blocks obtained by dividing the channel band to be received by the wireless reception unit, an initial synchronization channel to be used for initial synchronization is arranged symmetrically with respect to the DC subcarrier.
22 . The apparatus according to claim 20 , wherein in a band to receive a resource block including the DC subcarrier out of the resource blocks obtained by dividing the channel band to be received by the wireless reception unit, an initial synchronization channel to be used for initial synchronization is arranged symmetrically with respect to the DC subcarrier.