Transmission apparatus, reception apparatus, mobile communications system and transmission control method

Abstract

A disclosed transmission apparatus comprises a switching portion that switches radio access methods; a frequency domain signal generation portion that allocates a radio resource to a spread chip sequence on which one of a fast Fourier transformation and a series/parallel conversion is performed in accordance with the switched radio accessed method, so as to generate a signal in a frequency domain; and a transmission signal generation portion that performs a fast inverse Fourier transformation on the signal in the frequency domain so as to generate a transmission signal.

1 . A transmission apparatus usable in a communications system of a single-carrier method and a communications system of a multi-carrier system, the transmission apparatus comprising:
 a switching portion that switches radio access methods;   a frequency domain signal generation portion that allocates a radio resource to a spread chip sequence on which one of a fast Fourier transformation and a series/parallel conversion is performed in accordance with the switched radio accessed method, so as to generate a signal in a frequency domain; and   a transmission signal generation portion that performs a fast inverse Fourier transformation on the signal in the frequency domain so as to generate a transmission signal.   
   
   
       2 . The transmission apparatus as recited in  claim 1 , wherein the switching portion switches the radio access methods in accordance with information indicating the radio access method. 
   
   
       3 . The transmission apparatus as recited in  claim 1 , wherein the switching portion transmits a channel conditions measurement signal using a predetermined frequency band requested to be allocated when switching to the radio access method of the single-carrier method. 
   
   
       4 . The transmission apparatus as recited in  claim 1 , further comprising a pilot signal generation portion that imparts information indicating at least one of a requested frequency bandwidth of a data channel, an amount of transmission data, and a data rate, when switching to the radio access method of the single-carrier method. 
   
   
       5 . The transmission apparatus as recited in  claim 4 , wherein the pilot signal generation portion imparts information indicating a requested maximum transmission bandwidth of a pilot signal. 
   
   
       6 . The transmission apparatus as recited in  claim 5 , wherein the pilot signal generation portion transmits the pilot signal in accordance with a frequency bandwidth and center frequency assigned based on information indicating the requested maximum transmission bandwidth of the pilot signal. 
   
   
       7 . The transmission apparatus as recited in  claim 6 , wherein the pilot signal generation portion transmits the pilot signal by a frequency hopping method. 
   
   
       8 . The transmission apparatus as recited in  claim 7 , wherein the pilot signal generation portion transmits the pilot signal in each assigned frequency bandwidth by the frequency hopping method. 
   
   
       9 . The transmission apparatus as recited in  claim 1 , wherein the frequency domain signal generation portion repeats a predetermined number of times the spread chip sequence on which the fast Fourier transformation is performed, and shifts each chip sequence repeated the predetermined number of times so as to generate a predetermined chip pattern. 
   
   
       10 . The transmission apparatus as recited in  claim 1 , wherein the frequency domain signal generation portion allocates the radio resource depending on types of physical channels. 
   
   
       11 . The transmission apparatus as recited in  claim 10 , wherein the frequency domain signal generation portion allocates the radio resource on a time-scale of transmission time interval length of a frequency block when allocating the frequency block to the physical channel. 
   
   
       12 . The transmission apparatus as recited in  claim 10 , wherein the frequency domain signal generation portion allocates the radio resource so that at least a partial band of an allocated frequency band when a signal to be transmitted is a contention-based channel. 
   
   
       13 . The transmission apparatus as recited in  claim 10 , wherein the frequency domain signal generation portion allocates the radio resource in accordance with a scheduling result when the signal to be transmitted is assigned to a shared control channel. 
   
   
       14 . The transmission apparatus as recited in  claim 10 , wherein the frequency domain signal generation portion allocates the radio resource in accordance with a scheduling result when the signal to be transmitted is assigned to a shared data channel. 
   
   
       15 . The transmission apparatus as recited in  claim 14 , wherein the frequency domain signal generation portion allocates the radio resource in accordance with a scheduling result in a time domain in a frequency division multiplexing access method. 
   
   
       16 . The transmission apparatus as recited in  claim 15 , wherein the frequency domain signal generation portion allocates plural frequency blocks in accordance with the data rate. 
   
   
       17 . The transmission apparatus as recited in  claim 14 , wherein the frequency domain signal generation portion allocates the radio resource in accordance with a scheduling result in the time domain and the frequency domain. 
   
   
       18 . The transmission apparatus as recited in  claim 17 , wherein the frequency domain signal generation portion groups frequency blocks so as to perform allocation. 
   
   
       19 . The transmission apparatus as recited in  claim 14 , wherein the frequency domain signal generation portion changes an allocated bandwidth in accordance with the data rate when the single-carrier transmission is performed. 
   
   
       20 . A reception apparatus comprising:
 a radio access method determination portion that determines a radio access method used by a transmission apparatus; and   an imparting portion that imparts the determined radio access method.   
   
   
       21 . The reception apparatus as recited in  claim 20 , wherein the radio access method determination portion determines the radio access method in accordance with an environment where the reception apparatus is installed. 
   
   
       22 . The reception apparatus as recited in  claim 20 , wherein the radio access method determination portion determines the radio access method in accordance with a cell configuration. 
   
   
       23 . The reception apparatus as recited in  claim 20 , wherein the radio access method determination portion determines the radio access method for each transmission apparatus. 
   
   
       24 . The reception apparatus as recited in  claim 20 , wherein the radio access method determination portion determines the radio access method in accordance with a distance between the transmission apparatus and the reception apparatus. 
   
   
       25 . The reception apparatus as recited in  claim 20 , wherein the radio access method determination portion determines the radio access method in accordance with a transmission power in the transmission apparatus. 
   
   
       26 . The reception apparatus as recited in  claim 20 , further comprising a radio resource allocation determination portion that determines a frequency band to be allocated, in accordance with a frequency band in which a channel conditions measurement signal is transmitted, wherein the imparting portion transmits information indicating the determined frequency band. 
   
   
       27 . The reception apparatus as recited in  claim 26 , wherein the radio resource allocation determination portion allocates a frequency band within a range of a frequency band in which the channel conditions measurement signal is transmitted. 
   
   
       28 . The reception apparatus as recited in  claim 27 , wherein the radio resource allocation determination portion determines the transmission apparatus to which a frequency is to be allocated for each frequency allocation unit determined in advance, in accordance with at least one of reception power of the channel conditions measurement signal in the reception apparatus, a type of data to be transmitted by the transmission apparatus, transmission waiting time, and a maximum transmission power of each mobile station. 
   
   
       29 . The reception apparatus as recited in  claim 26 , wherein the radio resource allocation determination portion allocates continuous frequency bands to one transmission apparatus in accordance with reception characteristic for each transmission apparatus when the radio access method is determined to be the single-carrier method. 
   
   
       30 . The reception apparatus as recited in  claim 20 , further comprising a pilot signal assignation portion that determines a center frequency and transmission bandwidth of the pilot signal for each transmission apparatus and transmits information indicating the determined center frequency and transmission bandwidth of the pilot signal to corresponding transmission apparatuses. 
   
   
       31 . The reception apparatus as recited in  claim 30 , wherein the pilot signal assignation portion imparts the determined center frequency and transmission bandwidth of the pilot signal to the corresponding transmission apparatuses by transmitting a frequency block ID. 
   
   
       32 . The reception apparatus as recited in  claim 30 , wherein the pilot signal assignation portion determines the transmission bandwidth in accordance with a maximum transmission power of each transmission apparatus and a path-loss between each transmission apparatus and the reception apparatus. 
   
   
       33 . The reception apparatus as recited in  claim 32 , wherein the pilot signal assignation portion determines to set the transmission bandwidth to one of an integral multiple of and 2 n  times a minimum transmission bandwidth determined in a system. 
   
   
       34 . The reception apparatus as recited in  claim 33 , wherein the pilot signal assignation portion determines that the transmission bandwidth is a maximum bandwidth in which a received SINR expected when the transmission apparatus transmits the pilot signal with a maximum transmission power becomes a desired received SINR or more. 
   
   
       35 . The reception apparatus as recited in  claim 33 , wherein the pilot signal assignation portion determines that the transmission bandwidth is a minimum transmission bandwidth when a received SINR expected when the transmission apparatus transmits the pilot signal in a minimum transmission bandwidth becomes less than the desired received SINR. 
   
   
       36 . The reception apparatus as recited in  claim 34 , wherein the pilot signal assignation portion calculates the expected received SINR using an average path-loss between the reception apparatus and the transmission apparatus and an average interference power in the reception apparatus. 
   
   
       37 . The reception apparatus as recited in  claim 30 , wherein the pilot signal assignation portion determines the center frequency and transmission bandwidth of the pilot signal in accordance with a total up-link reception power. 
   
   
       38 . The reception apparatus as recited in  claim 37 , wherein the pilot signal assignation portion determines in advance a reference value indicating deviation in the reception power of the pilot signal in each transmission apparatus, and determines the center frequency and transmission bandwidth of the pilot signal for each transmission apparatus so that the deviation is the reference value or below. 
   
   
       39 . The reception apparatus as recited in  claim 37 , wherein the pilot signal assignation portion allocates the transmission bandwidth of the pilot signal so that the number of the transmission apparatuses that transmit the pilot signals is proportionate in each frequency band. 
   
   
       40 . The reception apparatus as recited in  claim 30 , wherein the pilot signal assignation portion determines the center frequency and transmission bandwidth of the pilot signal for each transmission apparatus in accordance with a remaining number of repetition factor. 
   
   
       41 . The reception apparatus as recited in  claim 30 , further comprising:
 a reception characteristic measurement portion that measures a reception characteristic of the pilot signal; and   a radio resource allocation determination portion that allocates the frequency band within a range of the transmission band of the pilot signal to each transmission apparatus in accordance with information indicating the reception characteristic, the transmission band of the pilot signal, and a requested frequency bandwidth of a data channel.   
   
   
       42 . The reception apparatus as recited in  claim 41 , wherein the radio resource allocation determination portion allocates the frequency band to each transmission apparatus in accordance with a frequency allocation unit determined in advance. 
   
   
       43 . The reception apparatus as recited in  claim 41 , wherein the radio resource allocation determination portion uses a reception characteristic measured in advance as the reception characteristic of a band in which the pilot signal is not transmitted. 
   
   
       44 . The reception apparatus as recited in  claim 41 , wherein the reception characteristic measurement portion measures the reception characteristic of the transmitted pilot signal using the frequency allocation unit determined in advance as a measurement unit. 
   
   
       45 . The reception apparatus as recited in  claim 41 , wherein the reception characteristic measurement portion measures the reception characteristic of the transmitted pilot signal using a requested allocation band of the data channel as a measurement unit. 
   
   
       46 . The reception apparatus as recited in  claim 26 , wherein the radio resource allocation determination portion assigns an up-link transmission power in accordance with the allocated frequency bandwidth. 
   
   
       47 . The reception apparatus as recited in  claim 26 , wherein the radio resource allocation determination portion assigns a transmission power in accordance with an interference power in a band to be allocated so that a ratio of a requested radiowaves power to the interference power becomes a predetermined power. 
   
   
       48 . The reception apparatus as recited in  claim 26 , wherein the radio resource allocation determination portion sets at least one of a required quality for a data channel and a required quality for the channel conditions measurement signal. 
   
   
       49 . The reception apparatus as recited in  claim 48 , wherein the radio resource allocation determination portion imparts at least one of the required quality for the data channel and the required quality for the channel conditions measurement signal through a broadcast channel. 
   
   
       50 . The reception apparatus as recited in  claim 48 , wherein the radio resource allocation determination portion controls the transmission power in accordance with the required quality for the channel conditions measurement signal when no data channel is allocated. 
   
   
       51 . The reception apparatus as recited in  claim 48 , wherein the radio resource allocation determination portion controls the transmission power for a channel conditions measurement signal portion and a data portion time-multiplexed in a transmission frame in accordance with the required quality for the data channel, when the data channel is allocated. 
   
   
       52 . The reception apparatus as recited in  claim 26 , wherein the radio resource allocation determination portion assigns the transmission power so as to realize substantially a constant transmission power density. 
   
   
       53 . The reception apparatus as recited in  claim 46 , wherein when the transmission apparatus to which the frequency band is allocated transmits a signal in accordance with an assigned transmission power and the reception power of the channel conditions measurement signal, the radio resource allocation determination portion determines use of one of the instantaneous value and the average value of the reception power of the signal transmitted by the transmission apparatus in the reception apparatus and the interference power, and determines a modulation method and an error correction code rate in accordance with a ratio of the determined reception power to the determined interference power. 
   
   
       54 . The reception apparatus as recited in  claim 53 , wherein the radio resource allocation determination portion determines MCS in accordance with the reception quality of the pilot signal measured for each frequency allocation unit and imparts the determined MCS to the transmission apparatus. 
   
   
       55 . The reception apparatus as recited in  claim 53 , wherein the radio resource allocation determination portion determines MCS in accordance with the reception quality of the pilot signal in the allocated frequency band and imparts the determined MCS to the transmission apparatus. 
   
   
       56 . The reception apparatus as recited in  claim 46 , wherein once the radio resource allocation determination portion allocates a frequency band to a transmission apparatus, the radio resource allocation determination portion continues to allocate the frequency band to the same transmission apparatus in a time-wise manner until a reception power changes to exceed a threshold value determined in advance, the transmission power being of the channel conditions measurement signal of the transmission apparatus in the allocated frequency band. 
   
   
       57 . A mobile communications system including a reception apparatus and a transmission apparatus usable in a communications system of a single-carrier method and a communications system of a multi-carrier system, the communications system comprising:
 a radio access method determination portion that determines a radio access method used by the transmission apparatus;   an imparting portion that imparts information indicating the determined radio access method;   a switching portion that switches radio access methods;   a frequency domain signal generation portion that allocates a radio resource to a spread chip sequence on which one of a fast Fourier transformation and a series/parallel conversion is performed in accordance with the switched radio access method so as to generate a signal in a frequency domain; and   a transmission signal generation portion that performs a fast inverse Fourier transformation on the signal in the frequency domain so as to generate a transmission signal.   
   
   
       58 . A transmission control method comprising:
 a step in which a reception apparatus determines a radio access method to be used;   a step in which the reception apparatus imparts information indicating the determined radio access method;   a step in which a transmission apparatus receives information indicating the radio access method;   a step in which the transmission apparatus switches radio access methods in accordance with the information indicating the radio access method;   a step in which the transmission apparatus allocates a radio resource to a spread chip sequence on which one of a fast Fourier transformation and a series/parallel conversion performed is performed so as to generate a signal in a frequency domain; and   a step in which the transmission apparatus performs a fast inverse Fourier transformation on the signal in the frequency domain so as to generate a transmission signal.   
   
   
       59 . The transmission control method as recited in  claim 58 , further comprising a step in which the transmission apparatus transmits, to the reception apparatus, information indicating at least one of a requested frequency bandwidth of a data channel, a quantity of transmission data, and a data rate. 
   
   
       60 . The transmission control method as recited in claim  59 , further comprising a step in which the transmission apparatus transmits information indicating a requested maximum transmission bandwidth of the pilot signal. 
   
   
       61 . The transmission control method as recited in  claim 59 , further comprising a step in which the transmission apparatus transmits the pilot signal in accordance with a frequency bandwidth and center frequency assigned in accordance with the information indicating the requested maximum transmission bandwidth of the pilot signal. 
   
   
       62 . The transmission apparatus as recited in  claim 61 , wherein the pilot signal is transmitted by a frequency hopping method in the step in which the transmission apparatus transmits the pilot signal. 
   
   
       63 . The transmission control method as recited in  claim 58 , wherein the step in which the transmission apparatus allocates the radio resource includes
 a step in which the spread chip sequence on which the fast Fourier transformation is performed is repeated a predetermined number of times; and   a step in which each chip sequence repeated the predetermined number of times are shifted so as to generate a predetermined chip pattern.   
   
   
       64 . The transmission control method as recited in  claim 58 , wherein the step in which the transmission apparatus allocates the radio resource includes a step in which the radio resource is allocated in accordance with types of physical channels. 
   
   
       65 . The transmission control method as recited in  claim 64 , wherein the step in which the radio resource is allocated includes a step in which the radio resource is allocated using a transmission time interval of a frequency block as a unit when the frequency block is allocated to the physical channel. 
   
   
       66 . The transmission control method as recited in  claim 64 , wherein the step in which the radio resource is allocated includes a step in which the radio resource is allocated in accordance with a scheduling result when a signal to be transmitted is assigned to a shared data channel. 
   
   
       67 . The transmission control method as recited in  claim 66 , wherein the step in which the radio resource is allocated includes a step in which the radio resource is allocated in accordance with a scheduling result in a time domain in a frequency division multiplexing access method. 
   
   
       68 . The transmission control method as recited in  claim 67 , wherein the step in which the radio resource is allocated includes a step in which plural frequency blocks are allocated in accordance with a data rate. 
   
   
       69 . The transmission control method as recited in  claim 64 , wherein the step in which the radio resource is allocated includes a step in which the radio resource is allocated in accordance with a scheduling result in the time domain and the frequency domain. 
   
   
       70 . The transmission control method as recited in  64 , wherein the step in which the radio resource is allocated includes a step in which frequency blocks are grouped and allocated. 
   
   
       71 . The transmission control method as recited in  claim 66 , wherein the step in which the radio resource is allocated includes a step in which a bandwidth to be allocated is changed in accordance with the data rate when a single-carrier transmission is performed. 
   
   
       72 . The transmission control method as recited in  claim 64 , wherein the step in which the radio resource is allocated includes a step in which a frequency band is allocated within a range of the frequency band in which a channel conditions measurement signal is transmitted. 
   
   
       73 . The transmission control method as recited in  claim 72 , wherein the step in which the radio resource is allocated includes a step in which there is determined a mobile station to which a frequency is allocated for each frequency allocation unit in accordance with at least one of a transmission power of the channel conditions measurement signal in the transmission apparatus, types of data that the mobile station is to transmit, a transmission waiting time, and a maximum transmission power of each mobile station. 
   
   
       74 . The transmission control method as recited in  claim 72 , wherein the step in which the radio resource is allocated includes a step in which continuous frequency bands are allocated to one mobile station in accordance with a reception characteristic of each mobile station when the radio access method is determined to be the single-carrier method. 
   
   
       75 . The transmission control method as recited in  claim 58 , further comprising:
 a step in which the reception apparatus assigns a center frequency and a transmission bandwidth of a pilot signal for each transmission apparatus in accordance with information indicating a requested maximum transmission bandwidth of the pilot signal; and   a step in which the reception apparatus transmits information indicating the determined center frequency and transmission bandwidth of the pilot signal to a corresponding transmission apparatus.   
   
   
       76 . The transmission control method as recited in  claim 75 , wherein the information indicating the determined center frequency and the transmission bandwidth is imparted to a corresponding transmission apparatus by transmitting a frequency block ID in the step in which the reception apparatus transmits the information. 
   
   
       77 . The transmission control method as recited in  claim 75 , wherein the transmission bandwidth is determined in accordance with a maximum transmission power of each transmission apparatus and a path-loss between each transmission apparatus and the reception apparatus, in the step in which the reception apparatus assigns the center frequency and the transmission bandwidth. 
   
   
       78 . The transmission control method as recited in  claim 77 , wherein the transmission bandwidth is determined to be one of an integral multiple of and 2 n  times a minimum transmission bandwidth determined in a system in the step in which the reception apparatus assigns the center frequency and transmission bandwidth. 
   
   
       79 . The transmission control method as recited in  claim 78 , wherein the transmission bandwidth is determined to be a maximum bandwidth in which a received SINR expected when the transmission apparatus transmits the pilot signal with a maximum transmission power becomes a required received SINR or more in the step in which the reception apparatus assigns the center frequency and the transmission bandwidth. 
   
   
       80 . The transmission control method as recited in  claim 78 , wherein the transmission bandwidth is determined to be a minimum bandwidth when a received SINR expected when the transmission apparatus transmits the pilot signal with a maximum transmission power becomes less than a required received SINR in the step in which the reception apparatus assigns the center frequency and the transmission bandwidth. 
   
   
       81 . The transmission control method as recited in  claim 79 , wherein the expected received SINR is calculated using an average interference power in the reception apparatus and an average path-loss between the transmission apparatus and the reception apparatus in the step in which the reception apparatus assigns the center frequency and the transmission bandwidth. 
   
   
       82 . The transmission control method as recited in  claim 75 , wherein the center frequency and the transmission bandwidth of the pilot signal are determined in accordance with a total up-link reception power in the step in which the reception apparatus assigns the center frequency and the transmission bandwidth. 
   
   
       83 . The transmission control method as recited in  claim 75 , wherein the center frequency and the transmission bandwidth of the pilot signal are determined for each transmission apparatus in accordance with a remaining number of repetition factors in the step in which the reception apparatus assigns the center frequency and the transmission bandwidth. 
   
   
       84 . The transmission control method as recited in  claim 75 , further comprising:
 a step in which the reception apparatus measures a reception characteristic of the pilot signal; and   a step in which the reception apparatus allocates a frequency band within a range of a transmission band of the pilot signal to each transmission apparatus in accordance with information indicating the reception characteristic, the transmission band of the pilot signal and a requested frequency bandwidth.   
   
   
       85 . The transmission control method as recited in  claim 84 , wherein the frequency band is allocated to each transmission apparatus based on a frequency allocation unit determined in advance in the step in which the reception apparatus allocates the frequency band. 
   
   
       86 . The transmission control method as recited in  claim 84 , wherein a reception characteristic measured in advance is used as the reception characteristic for a band in which the pilot signal is not transmitted in the step in which the reception apparatus allocates the frequency band. 
   
   
       87 . The transmission control method as recited in  claim 84 , wherein the reception characteristic of the pilot signal is measured using a frequency band allocation unit as a measurement unit in the step in which the reception apparatus measures the reception characteristic of the pilot signal. 
   
   
       88 . The transmission control method as recited in  claim 84 , wherein a reception characteristic of a transmitted pilot signal is measured using a requested allocation band of the data channel as a measurement unit in the step in which the reception apparatus measures the reception characteristic of the pilot signal. 
   
   
       89 . The transmission control method as recited in  claim 65 , further comprising a step in which an up-link transmission power is assigned in accordance with an allocated frequency bandwidth. 
   
   
       90 . The transmission control method as recited in  claim 89 , wherein the transmission power is assigned in accordance with interference power in a band to be allocated so that a ratio of a requested radiowaves power to an interference power becomes a predetermined value in the step in which the up-link transmission power is assigned. 
   
   
       91 . The transmission control method as recited in  claim 65 , wherein at least one of a required quality for a data channel and a required quality for a channel conditions measurement signal is set in the step in which the up-link transmission power is assigned. 
   
   
       92 . The transmission control method as recited in  claim 91 , wherein at least one of the required quality for the data channel and the required quality for the channel conditions measurement signal is imparted through a broadcast channel in the step in which the up-link transmission power is assigned. 
   
   
       93 . The transmission control method as recited in  claim 91  wherein the transmission power is controlled in accordance with the required quality for the channel conditions measurement signal when no data channel is allocated in the step in which the up-link transmission power is assigned. 
   
   
       94 . The transmission control method as recited in  claim 91 , wherein the transmission power is controlled for a channel conditions measurement signal portion and a data portion time-multiplexed in a transmission frame in accordance with the required quality for the data channel in the step in which the up-link transmission power is assigned when the data channel is allocated. 
   
   
       95 . The transmission control method as recited in  claim 89 , wherein the step in which the up-link transmission power is assigned includes a step in which the transmission power is assigned so that a transmission power density is substantially constant. 
   
   
       96 . The transmission control method as recited in  claim 89 , further comprising:
 a step in which when the transmission apparatus to which the frequency band is allocated transmits a signal in accordance with an assigned transmission power and a reception power of the channel conditions measurement signal, use of one of an instantaneous value and an average value of the reception power of the signal transmitted by the transmission apparatus in the reception apparatus and the interference power is determined; and   a step in which a modulation method and an error correction code rate are determined in accordance with a ratio of the determined reception power to an interference power.   
   
   
       97 . The transmission control method as recited in  claim 96 , wherein MCS is determined in accordance with a reception quality of the pilot signal measured for each frequency allocation unit in the step in which the modulation method and the error correction code rate are determined. 
   
   
       98 . The transmission control method as recited in  claim 96 , wherein MCS is determined in accordance with a reception quality of the pilot signal in an allocation band in the step in which the modulation method and the error correction code rate are determined. 
   
   
       99 . The transmission control method as recited in  claim 65 , wherein once a frequency band is allocated to a transmission apparatus, the frequency band is continuously allocated to the same transmission apparatus in a time-wise manner until a reception power changes to exceed a threshold value determined in advance, the transmission power being of a channel conditions measurement signal of the transmission apparatus in the allocated frequency band, in the step in which the radio resource is allocated.