Patent Application
20170215084
This application is a divisional patent application of U.S. patent application Ser. No. 14/397,311, entitled “CONTROL APPARATUS, RADIO STATION, RADIO TERMINAL, AND METHOD OF CONTROLLING UTILIZATION OF SHARED FREQUENCY,” filed Oct. 27, 2014, which is a national stage application of International Application No. PCT/JP2013/000096 entitled “CONTROL APPARATUS, RADIO STATION, RADIO TERMINAL, AND METHOD OF CONTROLLING UTILIZATION OF SHARED FREQUENCY” filed on Jan. 11, 2013, which claims the benefit of the priority of Japanese Patent Application No. 2012-102335, filed on Apr. 27, 2012, the disclosures of each of which are hereby incorporated by reference in their entirety.
The present invention relates to control of utilization of a shared frequency by a radio communication system.
Cognitive radio recognizes a surrounding wireless environment and optimizes communication parameters according to the wireless environment. One example of cognitive radio is a case in which a plurality of radio systems share a frequency band. For example, there is a case in which a frequency band that can be preferentially used by one radio system (called a primary system) is secondarily used by another radio system (called a secondary system). It is discussed in Institute of Electrical and Electronic Engineers (IEEE) 802.22 to standardize a wireless regional area network (WRAN) corresponding to a secondary system which secondarily uses a frequency band (TV channel) licensed to a TV broadcasting system corresponding to a primary system.
When a secondary system secondarily uses a frequency band licensed to a primary system, it is necessary that the secondary system does not have any influence on services provided by the primary system. In order to avoid causing interference to the primary system, the secondary system uses a frequency band that is not temporally or spatially used by the primary system, or adjusts transmission power so that interference experienced by the primary system is below a tolerance level (see, e.g., patent literature 1).
A study has been actively carried out assuming a case in which, in one example of cognitive radio, a primary system is a TV broadcasting system and a secondary system is a cellular system. A frequency band which is not temporally or spatially used in a TV broadcasting system is called a TV white space (WS) (see, e.g., non-patent literature 1).
Some known examples of cognitive radio technology for specifying unused frequency bands include a Geo-location Database (GDB), frequency sensing, and a beacon (or Cognitive Pilot Channel (CPC)). Among these examples, two or more, e.g., a GDB and frequency sensing, or a GDB and a beacon, may be used in combination with each other. A GDB provides statuses of utilization of a shared frequency band (e.g., TV band) or information of a secondarily usable (i.e., unused) frequency band (e.g., TVWS), according to geographical locations.
For example, allocation of TVWS to a Long Term Evolution (LTE) system, which is a cellular system, is executed in the following procedure.
In the above example of allocating TVWS to a LTE system, a shared frequency (e.g., TVWS) may not be efficiently utilized. In the case of secondary utilization of TVWS, a radio communication system secondarily uses a frequency licensed to a TV broadcasting operator. The frequency licensed to the TV broadcasting operator is different from a frequency licensed to the radio communication system. Therefore, even when TVWS is allocated to a base station, the TVWS cannot be efficiently utilized unless a radio terminal belonging to a cell operated by the base station has communication capability on the TVWS. However, a radio communication system generally ensures backward compatibility. That is, a case is assumed in which the base station must provide communication services to old radio terminals (i.e., legacy terminals) which do not have communication capability on the TVWS. If most of radio terminals belonging to the cell are legacy terminals which do not have the communication capability on the TVWS, the base station cannot efficiently utilize the TVWS.
One object of the present invention is to provide a control apparatus, a radio station, a radio terminal, methods related thereto, and programs that contribute to efficient utilization of a shared frequency (e.g., TVWS) shared by a plurality of radio systems.
In a first aspect, a control apparatus includes a controller. The controller operates to control, based on at least one condition, utilization by a first radio station of a shared frequency shared by a plurality of radio systems including a radio communication system that includes the first radio station. The at least one condition includes a first condition regarding communication capability on the shared frequency of at least one radio terminal belonging to a cell operated by the first radio station.
In a second aspect, a radio station that is used in a radio communication system and communicates with at least one radio terminal is provided. The radio station includes a controller that operates to acquire terminal information regarding the at least one radio terminal and to control utilization by the radio station of a shared frequency shared by a plurality of radio systems including the radio communication system. The terminal information includes information regarding communication capability on the shared frequency of the at least one radio terminal.
In a third aspect, a radio terminal that is used in a radio communication system and communicates with a radio station is provided. The radio terminal includes a controller that operates to send terminal information regarding the radio terminal to the radio station which controls utilization of a shared frequency shared by a plurality of radio systems including the radio communication system. The terminal information includes information regarding communication capability on the shared frequency.
In a fourth aspect, a method of controlling utilization of a shared frequency is provided. The method includes controlling, based on at least one condition, utilization by a first radio station of a shared frequency shared by a plurality of radio systems including a radio communication system that includes the first radio station. The at least one condition includes a first condition regarding communication capability on the shared frequency of at least one radio terminal belonging to a cell operated by the first radio station.
In a fifth aspect, a method performed by a radio station that is used in a radio communication system and communicates with at least one radio terminal is provided. The method includes acquiring terminal information regarding the at least one radio terminal and controlling utilization by the radio station of a shared frequency shared by a plurality of radio systems including the radio communication system. The terminal information includes information regarding communication capability on the shared frequency of the at least one radio terminal.
In a sixth aspect, a method implemented in a radio terminal that is used in a radio communication system and communicates with a radio station is provided. The method includes sending terminal information regarding the radio terminal to the radio station which controls utilization of a shared frequency shared by a plurality of radio systems including the radio communication system. The terminal information includes information regarding communication capability on the shared frequency.
In a seventh aspect, a program is provided for causing a computer to execute the method according to the fourth aspect stated above.
In an eighth aspect, a program is provided for causing a computer to execute the method according to the fifth aspect stated above.
In a ninth aspect, a program is provided for causing a computer to execute the method according to the sixth aspect stated above.
According to aspects stated above, it is possible to provide a control apparatus, a radio station, a radio terminal, methods related thereto, and programs that contribute to efficient utilization of a shared frequency (e.g., TVWS) shared by a plurality of radio systems.
Hereinafter, with reference to the drawings, specific embodiments will be described in detail. Throughout the drawings, identical and corresponding components are denoted by the same reference symbols, and overlapping descriptions will be omitted as appropriate for the sake of clarification of description.
In one embodiment, a radio terminal used in a radio communication system and performing communication with a radio station is provided. The radio terminal according to this embodiment has a function of notifying a network of terminal information including information regarding communication capability on a shared frequency. The network includes a control entity which controls utilization of the shared frequency shared by a plurality of radio systems including the radio communication system. In this embodiment, since the radio terminal has a function of reporting the communication capability on the shared frequency, the control entity is able to take into consideration the communication capability on the shared frequency of the radio terminal to control utilization of the shared frequency by the radio communication system. According to this embodiment, the shared frequency can be efficiently utilized.
The terminal information includes, for example, terminal radio access capability or terminal system capability on the shared frequency. The terminal information may further include a terminal communication amount, a terminal service, and terminal location information. The terminal service indicates a type, attribute (e.g., real-time properties, importance, priority, or quality requirement), or service category of a service being executed or requested by the radio terminal. The terminal location information includes, for example, location information acquired by a Global Positioning System (GPS), or location information acquired by a location information service provided by a network (e.g., location information acquired by Observed Time Difference Of Arrival (OTDOA) method). Alternatively, the terminal location information may include radio quality measured by the radio terminal (e.g., a cell identifier and received quality of a known downlink signal of each cell).
The radio communication system 100 includes a radio station 1, a radio terminal 2, and a controller 3. The radio station 1 operates a cell 11 and communicates with the radio terminal 2 belonging to the cell 11. The radio station 1 is called, for example, a base station, a relay node (RN), or an access point. The radio terminal 2 is called, for example, a mobile station, a User Equipment (UE), or a Wireless Transmit/Receive Unit (WTRU). The cell 11 means a coverage area of the radio station 1. The cell 11 may be a sector cell.
The controller 3 operates to control, based on at least one condition, utilization by the radio station 1 of a shared frequency shared by a plurality of radio systems including the radio communication system 100. Note that the at least one condition includes a first condition regarding communication capability on the shared frequency of at least one radio terminal 2 belonging to the cell 11 operated by the radio station 1.
The shared frequency may be a frequency band licensed to a primary system (e.g., TVWS). In this case, for example, the radio communication system 100 as a secondary system can secondarily use the shared frequency when the shared frequency is not temporally or spatially used by the primary system. In other words, the radio communication system 100 can secondarily use the shared frequency (e.g., TVWS), which is not licensed (or not exclusively licensed) to the radio communication system 100, as well as a frequency licensed to the radio communication system 100. Note that the primary system may not exist. In such a case, the shared frequency may be equally shared by a plurality of radio communication systems, e.g., a plurality of radio communication systems operated by different operators. The plurality of radio communication systems may include only systems using the same radio access technology (e.g., LTE) or may include systems using different radio access technologies (e.g., LTE, CDMA2000, GSM, WiMAX).
As already described above, there is a case in which the radio communication system 100 is required to have backward compatibility, that is, to also provide communication services to radio terminals (legacy terminals) which do not have communication capability on the shared frequency. If most of the plurality of radio terminals 2 belonging to the cell 11 are legacy terminals which do not have communication capability on the shared frequency, the radio station 1 cannot efficiently utilize the shared frequency even when the shared frequency is allocated.
In order to address this problem, in this embodiment, the controller 3 controls utilization of the shared frequency by the radio station 1 based on the first condition regarding communication capability on the shared frequency of at least one radio terminal 2 belonging to the cell 11. The controller 3 may allow the radio station 1 to use the shared frequency in response to satisfaction of the first condition. In this case, the first condition may only indicate that the shared frequency is efficiently utilized in the cell 11. The first condition may be a condition indicating that a sufficient number of radio terminals 2 having communication capability on the shared frequency belong to the cell 11.
The first condition may be, for example, one of the following (1) to (10), or any combination thereof:
The “terminal radio access capability on the shared frequency” in the conditions (2) to (6) indicates that the radio terminal 2 has a capability of performing radio access to the radio station 1 using the shared frequency. The “terminal radio access capability on the shared frequency” is, for example, capability of using the shared frequency (i.e., whether communication is possible on the frequency band allocated as the shared frequency), or capability of measuring radio quality on the shared frequency (e.g., received power, interference power, Signal to Interference plus Noise Ratio (SINR)).
The “terminal system capability on the shared frequency” in the conditions (2) to (6) is, for example, capability that the radio terminal 2 performs communication with the radio station 1 using the shared frequency, or capability of cognitive radio (e.g., sensing capability) on the shared frequency.
The “total amount of traffic” in the conditions (3) and (8) means the sum of amounts of traffic of the plurality of radio terminals 2. It can be said that the amount of traffic of the radio terminal 2 is equal to volume of communication of the radio terminal 2. The amount of traffic of the radio terminal 2 is, for example, an amount of data communicated by the radio terminal in a certain period, or an amount of data per unit time (i.e., data rate, or throughput). The amount of traffic of the radio terminal 2 may be a predicted value of the amount of traffic which is expected to be generated in the future.
The “certain service” in the conditions (4), (5), (9), and (10) indicates a specific service, or a service category having a specific attribute. The specific attribute includes, for example, real-time property, importance, priority, or quality requirement. Specifically, the certain service may be a service with a large amount of communication which may increase the load of the cell 11.
The “certain area” in the conditions (6) and (7) indicates the geographical location of the radio terminal 2. The certain area may be a relative position from the radio station 1 (e.g., cell edge).
In Step S102, the controller 3 acquires information indicating the communication capability on the shared frequency of the radio terminal 2 belonging to the cell 11. Specifically, the controller 3 may acquire information of the radio terminal 2 including information indicating the communication capability on the shared frequency (hereinafter referred to as terminal information). The controller 3 uses the terminal information in order to determine whether to allow the utilization of the shared frequency by the radio station 1. The terminal information may therefore include information used for this determination.
The terminal information includes, for example, at least one of terminal radio access capability, terminal system capability, terminal communication amount, terminal service, and terminal location information. The terminal service indicates a type, attribute (e.g., real-time properties, importance, priority, or quality requirement), or service category of a service that is executed or requested by the radio terminal 2. The terminal location information includes, for example, location information acquired by a Global Positioning System (GPS), or location information acquired by a location information service provided by a network (e.g., location information acquired by Observed Time Difference Of Arrival (OTDOA) method). Alternatively, the terminal location information may include radio quality measured by the radio terminal 2 (e.g., a cell identifier and received quality of a known downlink signal of each cell). The radio terminal 2 may send at least a part of the terminal information to the controller 3. Further or alternatively, the radio station 1 may acquire and then send at least a part of the terminal information to the controller 3. Further or alternatively, at least a part of the terminal information may be supplied from a subscriber server which manages subscriber data (e.g., Home Subscriber Server (HSS), Home Location Register (HLR)).
In Step S103, the controller 3 determines, using the terminal information acquired in Step S102, at least one condition including the first condition regarding communication capability on the shared frequency of the radio terminal 2 belonging to the cell 11. The controller 3 allows the radio station 1 to use the shared frequency in response to satisfaction of the at least one condition. For example, the controller 3 may notify the radio station 1 of the shared frequency or a part of the shared frequency as an allocated frequency.
The controller 3 may take into consideration other conditions in addition to the first condition in order to determine whether to allow the radio station 1 to use the shared frequency. The controller 3 may take into consideration the geographical location of the radio station 1. More specifically, the controller 3 may determine whether or not the geographical location of the radio station 1 is within an area in which the utilization of the shared frequency is allowed. Further or alternatively, the controller 3 may take into consideration frequencies that are able to be utilized by the radio station 1. Specifically, the controller 3 may determine whether the shared frequency is within a frequency spectrum range that is able to be utilized by the radio station 1. Further or alternatively, the controller 3 may take into consideration the maximum or minimum value of the downlink transmission power of the radio station 1.
The controller 3 may carry out a procedure for updating the allocated frequency to be allocated to the radio station 1 periodically or in response to a change in the communication capability on the shared frequency of the radio terminal 2 belonging to the cell 11. The controller 3 may carry out a procedure for releasing the allocated frequency (i.e., procedure for stopping the utilization by the radio station 1 of the shared frequency). The controller 3 may stop the utilization by the radio station 1 of the shared frequency when, for example, at least one condition including the first condition is not satisfied.
As described above, this embodiment includes the controller 3. The controller 3 controls the utilization by the radio station 1 of the shared frequency based on the first condition regarding the communication capability on the shared frequency of at least one radio terminal 2 belonging to the cell 11. The first condition may be, for example, a condition indicating that a sufficient number of radio terminals 2 having communication capability on the shared frequency belong to the cell 11. This embodiment is thus able to contribute to the efficient utilization of the shared frequency shared by a plurality of radio systems.
Meanwhile, the arrangement of the controller 3 is determined as appropriate based on the design concept of the network architecture or based on the radio communication standard. As shown in
As shown in
Note that, in the example shown in
As shown in
In this embodiment, a specific example will be described of the arrangement of the controller 3 and the procedure for allocating the shared frequency to the radio station 1 described in the second embodiment. Specifically, this embodiment shows an example in which the controller 3 is integrally arranged with the radio station 1.
The radio stations 1A and 1B include controllers 3A and 3B, respectively. Each of the controllers 3A and 3B corresponds to the controller 3 described in the second embodiment. Each of the controllers 3A and 3B operates to receive terminal information AA from the radio terminal 2 (2A or 2B). Each of the controllers 3A and 3B determines the determination condition including the first condition stated above using the terminal information AA.
Each of the radio terminals 2A and 2B includes a controller 20. The controller 20 operates to send the terminal information AA to the radio station 1 (1A or 1B) operating the cell 11 (11A or 11B) to which the radio terminal 2 belongs.
The operation and management apparatus (OAM) 4 manages the plurality of radio stations 1 including the radio stations 1A and 1B. The operation and management apparatus (OAM) 4 communicates with a frequency management apparatus (SM) 5, and receives shared frequency information from the frequency management apparatus (SM) 5. The shared frequency information indicates an available shared frequency (i.e., at least one candidate frequency). Note that the operation and management apparatus (OAM) 4 may directly receive the shared frequency information from the Geo-location Database (GDB) without the intervention of the frequency management apparatus (SM) 5.
In Step S203, the operation and management apparatus (OAM) 4 acquires information of candidate frequencies that can be allocated among the shared frequencies. The operation and management apparatus (OAM) 4 may receive candidate frequency information from the frequency management apparatus (SM) 5 or the GDB. In Step S204, the operation and management apparatus (OAM) 4 sends a notification indicating at least one candidate frequency to the radio stations 1A and 1B.
In Step S205, the radio stations 1A and 1B determine, for each candidate frequency, whether to satisfy the determination condition including the first condition regarding the communication capability on the shared frequency of the radio terminal 2 (2A or 2B). The radio stations 1A and 1B each select, as the allocated frequency for its cell, a candidate frequency which satisfies the determination condition.
In Step S206, the radio stations 1A and 1B each send a report indicating the allocated frequency to the operation and management apparatus (OAM) 4. When none of the candidate frequencies satisfy the determination condition including the first condition, the radio stations 1A and 1B may each send to the operation and management apparatus (OAM) 4 a report indicating frequency allocation is not performed. In Step S207, the operation and management apparatus (OAM) 4 updates candidate frequency information based on the report from the radio stations 1A and 1B. Note that Step S207 may be omitted.
The procedure shown in
Step S302 corresponds to Step S201 shown in
Step S304 corresponds to Step S204 shown in
Step S307 corresponds to Step S206 shown in
Similar to the description in the second embodiment, the controllers 3A and 3B may each execute a procedure for releasing the allocated frequency (i.e., procedure for stopping the utilization by the radio station 1 of the shared frequency). Described below is a specific example of a procedure for stopping the utilization of the shared frequency.
The procedure shown in
In this embodiment, the determination condition including the first condition used to determine whether to allow the utilization of the shared frequency may be configured in advance in the radio stations 1A and 1B (controllers 3A and 3B). Alternatively, this determination condition may be sent from the operation and management apparatus (OAM) 4 to the radio stations 1A and 1B together with the candidate frequency notification. The determination condition may be the same or different for the candidate frequencies. Further, the determination condition may be the same or different for the plurality of radio stations 1.
Further, when notifying the radio stations 1A and 1B of the candidate frequencies, the operation and management apparatus (OAM) 4 may send to the radio stations 1A and 1B the upper limit value of the downlink transmission power. Further, the operation and management apparatus (OAM) 4 may send to the radio stations 1A and 1B an absolute time or a relative time indicating the time limit that the candidate frequencies can be utilized. The upper limit value and the absolute or relative time may be the same or different for the candidate frequencies.
In this embodiment, a specific example of the arrangement of the controller 3 and the procedure for allocating the shared frequency to the radio station 1 described in the second embodiment will be described. Specifically, this embodiment shows an example in which the controller 3 is integrally arranged with the operation and management apparatus (OAM) 4.
In Step S604, the operation and management apparatus (OAM) 4 sends the request for a terminal information report to the radio stations 1A and 1B. In Step S605, the radio stations 1A and 1B send the terminal information report to the operation and management apparatus (OAM) 4. The terminal information report of the radio station 1A includes terminal information regarding the radio terminal 2A belonging to the cell 11A. As already described above, the terminal information is used to determine whether to allow the radio station 1 to use the shared frequency. The terminal information includes, for example, at least one of terminal radio access capability, terminal system capability, terminal communication amount, terminal service, and terminal location information.
In Step S606, the operation and management apparatus (OAM) 4 determines the allocated frequency for each of the radio stations 1A and 1B. In other words, the operation and management apparatus (OAM) 4 determines whether to allow the utilization of the shared frequency for each of the radio stations 1A and 1B. In the determination in Step S606, the determination condition including the first condition stated above is used.
In Step S607, the operation and management apparatus (OAM) 4 notifies each of the radio stations 1A and 1B of the allocated frequency. When none of the candidate frequencies satisfy the condition, the operation and management apparatus (OAM) 4 notifies the corresponding radio station 1 that the frequency allocation is not conducted.
The procedure shown in
Steps S704 and S705 in
Step S706 shown in
Steps S804 and S805 correspond to Step S606 shown in
Step S806 corresponds to Step S607 shown in
In this embodiment, the determination condition including the first condition used to determine availability of the shared frequency may be configured in advance in the operation and management apparatus (OAM) 4. Alternatively, the determination condition may be sent to the operation and management apparatus (OAM) 4 together with the information indicating the candidate frequencies from another apparatus or system such as a frequency management apparatus (SM) 5. The determination condition may be the same or different for the candidate frequencies. Further, the determination condition may be the same or different for the plurality of radio stations 1.
Further, when notifying the radio stations 1A and 1B of the allocated frequency, the operation and management apparatus (OAM) 4 may send to the radio stations 1A and 1B the upper limit value of the downlink transmission power. Further, the operation and management apparatus (OAM) 4 may send to the radio stations 1A and 1B an absolute time or a relative time indicating the time limit that the candidate frequencies can be utilized. The upper limit value and the absolute or relative time may be the same or different for the candidate frequencies.
In this embodiment, a modified example of the fourth embodiment will be described. Shown in this embodiment is an example in which the controller 3 is integrally arranged with the operation and management apparatus (OAM) 4, similar to the fourth embodiment. However, this embodiment shows a modified example of the signaling between the radio station 1 and the operation and management apparatus (OAM) 4. Specifically, the operation and management apparatus (OAM) 4 receives from the radio station 1 the terminal information report together with the request for allocation of the shared frequency. Alternatively, the operation and management apparatus (OAM) 4 may receive the terminal information report from the radio station 1 instead of receiving the request for the allocation of the shared frequency. This makes it possible to reduce the signaling between the operation and management apparatus (OAM) 4 and the radio station 1.
The configuration example of the radio network including the radio communication system 100 according to this embodiment may be similar to the configuration according to the fourth embodiment shown in
Described in detail in this embodiment is a case in which the radio communication system 100 according to the first to fifth embodiments stated above is an LTE system. When the radio communication system 100 is an LTE system, the radio station 1 corresponds to a radio base station (i.e., eNB) and the radio terminal 2 corresponds to a UE.
Further, the conditions (1) to (10) indicated as the specific examples of the first condition regarding the communication capability of the UE 2 in the shared frequency and the terminal radio access capability described regarding the specific example of the terminal information can be called “UE radio access capability”. The UE radio access capability includes, for example, information (i.e., SupportedBandListEUTRA information) regarding whether or not the UE is able to perform communication on a candidate frequency to be allocated. The SupportedBandListEUTRA information is one of the information elements contained in UE Capability Information transmitted from the UE to the Evolved Universal Terrestrial Radio Access Network (E-UTRAN). The SupportedBandListEUTRA information indicates a frequency band supported by the UE 2. Further, the UE radio access capability may include information (i.e., SupportedBandCombination information) indicating capability of concurrently using the frequency band of current camped cell and the candidate frequency to be allocated.
The terminal system capability can be called “UE Non-Access-Stratum (NAS) capability”. The UE NAS capability may include information (i.e., CognitiveCapability information) indicating presence or absence of cognitive radio capability (e.g., sensing capability). In the LTE, a mobility management apparatus (Mobility Management Entity (MME)) located within a core network (Evolved Packet Core (EPC)) acquires the terminal system capability (UE NAS capability) from the radio terminal through the radio base station (eNB). When the terminal system capability (UE NAS capability) is used in the radio base station (eNB), the eNB acquires it from the MME.
Further, when the shared frequency is utilized for inter-terminal direct communication (called UE direct communication, D2D (Device-to-Device) communication, UE-to-UE communication or the like), the terminal system capability may include information indicating presence or absence of inter-terminal direct communication capability. The inter-terminal communication capability may be defined as terminal radio access capability, not as terminal system capability.
Further, the terminal service indicated as a specific example of the terminal information may be a Quality of Service (QoS) or a QoS Class Indicator (QCI) of the service being executed or requested by the UE 2.
Further, the terminal location information indicated as a specific example of the terminal information may be location information acquired by a GPS or may be location information acquired by a location information service (Location Service (LCS)) provided by a network (e.g., location information acquired by the OTDOA method). The terminal location information may be the radio quality measured by the UE 2 (e.g., cell identifier and received quality of the reference signal of each cell). The radio quality measured by the UE 2 is also called an RF fingerprint.
Described below in detail in this embodiment is a case in which the radio communication system 100 according to the third embodiment stated above is an LTE system and the shared frequency is TVWS. In summary, this embodiment shows an example in which the controller 3 is integrally arranged with the radio station (i.e., eNB) 1.
Similarly, the LTE system 100B includes two eNBs 1C and 1D. The eNB 1C operates a cell 11C and communicates with a UE 2C belonging to the cell 11C. In a similar way, the eNB 1D operates a cell 11D and communicates with a UE 2D belonging to the cell 11D. An operation and management apparatus (OAM) 4B manages a plurality of radio stations 1 (including the eNBs 1C and 1D) included in the LTE system 100B.
The operation and management apparatuses (OAMs) 4A and 4B communicate with the frequency management apparatus (SM) 5 and receive the shared frequency information from the frequency management apparatus (SM) 5. The shared frequency information indicates an available shared frequency (i.e., at least one candidate frequency). The operation and management apparatuses (OAMs) 4A and 4B may directly receive the shared frequency information from the Geo-location Database (GDB) 6 without the intervention of the frequency management apparatus (SM) 5. The GDB 6 manages the status of utilization of the frequency band (i.e., TV band) licensed to the TV broadcasting system 200 and provides information of the frequency band (e.g., TVWS) which can be secondarily used.
The processing in Steps S201, S202, and S204 to S207 shown in
Steps S1203 and S1204 in
The procedure shown in
Described below in detail in this embodiment is a case in which the radio communication system 100 according to the fifth embodiment stated above is an LTE system and the shared frequency is TVWS. That is, shown in this embodiment is an example in which the controller 3 is integrally arranged with the operation and management apparatus (OAM) 4.
The processing in Steps S201, S902, S606, and S607 shown in
In Step S1304 shown in
The procedure shown in
The eighth embodiment described above may be modified as described below. Shown in the eighth embodiment is the example in which the operation and management apparatuses (OAMs) 4A and 4B of each operator determine the allocated frequency from the candidate frequencies (i.e., TVWS). However, the frequency management apparatus (SM) 5 may perform frequency allocation (i.e., frequency management) for a plurality of operator networks. In this case, in
The frequency management apparatus (SM) 5 determines the allocated frequency for the eNBs 1A and 1C in response to the frequency allocation request. The frequency management apparatus (SM) 5 then sends to the management apparatus (OAM) 4A a notification indicating the frequency to be allocated to the eNB 1A, and also send to the management apparatus (OAM) 4B a notification indicating the frequency to be allocated to the eNB 1C. The operation and management apparatuses (OAMs) 4A and 4B send to the eNBs 1A and 1C respectively a notification indicating the allocated frequency. The eNBs 1A and 1C each start communication with the UE 2A or 2C on each allocated frequency.
As stated above, a network node (or apparatus) such as the frequency management apparatus (SM) 5 allocates frequencies to a plurality of operator networks (or a plurality of operator systems), thereby making it possible to maintain equality among operators and to select the optimum operator network (or operator system) as the destination to which the shared frequency is allocated.
In the eighth and ninth embodiments regarding the LTE system, the case in which the TVWS is utilized in the LTE system is exemplified. Needless to say, however, the eighth and ninth embodiments may also be applied to a case in which there is no primary system like the TV broadcasting system 200 and a plurality of systems share a frequency. The plurality of systems may be a plurality of LTE systems or may include the LTE system and other system.
The processing performed by the controller 3 (or 3A to 3D) and the controller 20 described in the first to ninth embodiments may be implemented by using a semiconductor processing device including an Application Specific Integrated Circuit (ASIC). Further, this processing may be implemented by causing a computer system including at least one processor (e.g., microprocessor, MPU, Digital Signal Processor (DSP)) to execute a program. Specifically, one or more programs including instructions for causing a computer system to execute the algorithms regarding the controller 3 or the controller 20 described in the first to ninth embodiments may be created and supplied to the computer.
The program can be stored and provided to a computer using any type of non-transitory computer readable media. Non-transitory computer readable media include any type of tangible storage media. Examples of non-transitory computer readable media include magnetic storage media (such as flexible disks, magnetic tapes, hard disk drives, etc.), optical magnetic storage media (e.g., magneto-optical disks), Compact Disc Read Only Memory (CD-ROM), CD-R, CD-R/W, and semiconductor memories (such as mask ROM, Programmable ROM (PROM), Erasable PROM (EPROM), flash ROM, Random Access Memory (RAM), etc.). The program may be provided to a computer using any type of transitory computer readable media. Examples of transitory computer readable media include electric signals, optical signals, and electromagnetic waves. Transitory computer readable media can provide the program to a computer via a wired communication line (e.g., electric wires, and optical fibers) or a wireless communication line.
Furthermore, the embodiments stated above are merely examples of application of the technical ideas obtained by the present inventors. Needless to say, these technical ideas are not limited to those described in the above embodiments, but may be changed in various ways.
This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2012-102335, filed on Apr. 27, 2012, the disclosure of which is incorporated herein in its entirety by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012-102335 | Apr 2012 | JP | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14397311 | Oct 2014 | US |
| Child | 15406012 | US |
