JP2014529916A - Master node, sensor node, communication system, method, and program - Google Patents

Abstract

A cognitive radio system including a master node and a plurality of mobile terminals is provided. A master node receives primary user transmission information indicating signal strength of primary user transmission from at least one mobile node (5), means for acquiring location information of each mobile node (5), Means for evaluating an area (17) where duplication of communication may occur between the master node (3) and the primary user (4) using the received primary user transmission information and the acquired location information; A means for comparing the position of the node (5) with the evaluated area (17) where duplication of communication may occur, and the operation of the mobile node (5) is controlled based on the comparison result, and the master node (3) And means for avoiding interference to the primary user (4) by the mobile node (5). [Selection] Figure 1

Description

  The present invention relates to a communication system, a part thereof, and a method thereof, and more particularly to a cognitive radio system and a device thereof.

  Conventionally, in wireless communication, a license has been granted to a system that exclusively uses a distinguishable block of the electromagnetic spectrum. This is a good way to remove the risk of harmful interference, but if it is not used by the licensee, a large number of allocated spectrum blocks will remain underutilized.

  In order to make the spectrum hall (the part of the spectrum where the license is not used at a given time) work, the idea of using the spectrum reasonably has been proposed. The idea includes two different types of spectrum users: legitimate users (authorized primary users) and secondary users (or cognitive users). Here, the secondary user is allowed to use a part of the spectrum only when the primary user does not use it or only when the interference that occurs (to the primary user) is within an acceptable range.

  A cognitive radio device is defined as a terminal that can recognize an electromagnetic environment and adapt its communication accordingly. In order to evaluate the occupation state of a specific frequency band, the cognitive radio apparatus can sense the frequency band and determine whether to transmit. However, the primary signal to be detected is exposed to different environmental changes (shielding, decay, path loss), making it extremely difficult for authorized primary users to detect cognitive radio devices by signal. In such a case, the primary transmitter is considered hidden from the sensing device (ie, the hidden primary transmitter), and the use of a single sensing device cannot make a reliable decision.

  If the primary user transmits at low power and narrow bandwidth (eg wireless microphone, similar to so-called “PMSE” devices), sensing in a specific area far away from the primary transmitter is not reliable.

  To address this issue, many geographically dispersed sensor nodes are used to sense the primary transmitter over a wide area and report back to the master node to determine if the secondary user can operate in the allowed band A collaborative approach is proposed. For example, International Publication No. 2007/031956 discloses such an interlocking system.

  However, the problem with such a collaborative approach is that the sensor node needs to be clearly instructed when and what frequency to sense and when to report back to the master node. Another problem is that the master node relies on the upper layer of the communication stack that controls the operation of the sensor node, and the master node that performs the operation of stopping the communication between the secondary user and the sensor node that sends a signal to the primary existence. It is a point that introduces a relatively long delay in between. This will cause undesired interference to authorized primary users while turning around and receiving and processing such signals at the master node.

  Yet another problem with such a collaborative approach is that the master node is farther away from the primary user than the sensor node, the master node restricts information about the primary user's communication characteristics, and the area in which the master node operates. It is a point that makes the use of resources inefficient.

  An object of the present invention is to provide a selective cooperation system that detects and reports transmission characteristics of a primary user and controls transmission opportunities of secondary users.

The present invention is a master node for use with a plurality of mobile nodes,
Receiving means for receiving, from the at least one mobile node, primary user transmission information indicating a signal strength of a primary user transmission received by the at least one mobile node;
Obtaining means for obtaining position information relating to each of the at least one mobile node;
An evaluation means for evaluating an area where duplication of communication may occur between the master node and the received primary user transmission information and the primary user, using the received primary user transmission information and the acquired position information;
A comparison means for comparing the position of each mobile node with the evaluated area where duplication of communication may occur;
In order to avoid interference with the primary user by the master node and the mobile node, a master node comprising control means for controlling the operation of the mobile node based on the comparison result is provided.

  In one embodiment, the receiving means receives information with media access control, MAC, and control element.

  In one embodiment, the acquisition means acquires the location information regarding each of the at least one mobile node from the mobile node. Alternatively, the acquisition unit acquires the position information related to each of the at least one mobile node from communication with a positioning system or another master node.

  In one embodiment, the control means prevents use of a band for the primary user transmission, executes a handover to a band different from the band for the primary user transmission, and transmits power of the mobile node in the band for the primary user transmission. The operation of the mobile node is controlled using at least one of the following restrictions and permission for the mobile node to continue communication in the band of the primary user transmission.

  In one embodiment, the control means controls transmission power and / or transmission direction of the master node in a band of the primary user transmission in order to avoid interference with the primary user.

  In one embodiment, the control means includes the primary user transmission information in a MAC control element to cause at least one mobile node of a plurality of mobile nodes to stop transmission in the band of the primary user transmission. Works to send to said at least one mobile node.

The present invention is also a sensor node in which a sensor node is used together with a master node, and the sensor node and the master node can communicate with each other in an operation band permitted for a primary user device,
Sensing means for sensing transmission of the primary user device;
Measuring means for measuring the magnitude of the sensed signal intensity of the primary user transmission;
Reporting means for reporting the magnitude of the measured signal strength to the master node,
The reporting means provides a sensor node that serves to report the magnitude of the measured signal strength in media access control, MAC, and layer frames for processing by the MAC entity of the master node.

  In one embodiment, the reporting means reports the measured signal strength magnitude in the MAC control element. The reporting means may report the display of the position information of the sensor node.

  In one embodiment, the sensor node stops communication in the primary user transmission band. This may be after the sensor node has received confirmation from the master node.

The present invention is also a master node for use with a plurality of mobile nodes,
Receiving means for receiving, from the at least one mobile node, primary user transmission information indicating a signal strength of a primary user transmission received by the at least one mobile node;
Control means for controlling the operation of the mobile node based on the primary user transmission information to avoid interference to the primary user by the master node and the mobile node, and
The receiving means operates in the media access control, MAC, layer of the master node and provides a master node arranged to extract primary user transmission information from the MAC layer frame.

  In one embodiment, the receiving means receives the primary user transmission information in a MAC control element.

  The master node may further include transmission means for sending an approval to the at least one mobile node and causing the at least one mobile node to stop transmission in the band of the primary user transmission.

  A master node sends the primary user transmission information to at least one of the plurality of mobile nodes in a MAC control element, and causes the at least one mobile node to stop transmission in the band of the primary user transmission May be further provided.

The present invention is also a sensor node in which a sensor node is used together with a master node, and the sensor node and the master node communicate with each other in an operation band permitted for a primary user device,
Communication control means for receiving uplink resource allocation data for designating uplink resources that the sensor node can use for data transmission to the master node;
Sensing means for sensing transmission of the primary user device;
Reporting means for reporting the measured magnitude of signal strength to the master node using uplink resources allocated by the master node;
When the sensing node senses the primary user transmission when the sensor node is not assigned an uplink resource, the communication control means is arranged to request allocation of an uplink resource from the master node. Provide a sensor node.

  In one embodiment, the reporting means reports the primary user transmission information and the indication of the sensed primary user transmission in a message transmitted by the sensor node as part of the random access procedure. The message is an uplink request message of a random access procedure, and may include a reserved preamble that notifies the master node of detection of primary user transmission in the allowed operating band.

  In one embodiment, the reporting means reports primary user transmission information within the MAC control element. The reporting means may report the magnitude of the measured signal strength after the sensor node further transmits a message as part of the random access procedure and uplink resources are given to the sensor node.

The present invention is also a master node for use with a plurality of mobile nodes,
Receiving means for receiving, from the at least one mobile node, primary user transmission information indicating a signal strength of a primary user transmission received by the at least one mobile node;
Control means for controlling the operation of the mobile node based on the temporary transmission user information in order to avoid interference with the primary user by a master node and a mobile node;
The receiving means provides a master node arranged to receive the primary user transmission information in a message transmitted by the at least one mobile node as part of a random access procedure.

  In one embodiment, the master node receives a notification of a sensed primary user transmission in an uplink request message sent by the mobile node as part of a random access procedure. The uplink request message may include a reserved preamble that notifies the master node of detection of primary user transmission in the permitted operating band.

  In one embodiment, the control means controls the master node and the plurality of mobile nodes in response to receiving an uplink request message including the reserved preamble, and controls the master node and the mobile node. It works to avoid interference to the primary user by the node.

  In one embodiment, the receiving means receives the primary user transmission information in a MAC control element. The primary user transmission information may be received after a mobile node further sends a message as part of a random access procedure and is given uplink resources to the mobile node.

The present invention is also a sensor node in which a sensor node is used together with a master node, and the sensor node and the master node can communicate with each other in an operation band permitted for a primary user device,
Means for storing a reserved preamble;
Sensing means for sensing transmission of the primary user device;
Reporting means for reporting a sensed primary user transmission to the master node;
The reporting means provides a sensor node that serves to report to the master node by storing and sending the reserved preamble in an initial message of a random access procedure.

  The reserved preamble may be pre-programmed at the sensor node, but is preferably received as part of the system information broadcast by the master node.

  In one embodiment, the sensor node comprises means for measuring the magnitude of the signal strength of the primary user transmission. The sensor node may send the measured signal strength to the master node using the uplink resource allocation received from the master node.

  In one embodiment, the sensor node further comprises means for randomly generating a preamble used in a random access procedure. In this case, the sensor node serves to compare the randomly generated preamble with the stored reserved preamble, and the randomly generated preamble and the reserved preamble stored. If they match, the sensor node randomly generates another preamble used in the random access procedure.

The present invention is also a master node in which a master node is used with a plurality of mobile nodes, and the master node and the mobile node can communicate with each other in an operation band permitted for a primary user device,
Means for receiving an initial message of a random access procedure from at least one mobile node;
Means for processing the received initial message to determine whether the mobile node that transmitted the initial message senses a primary user transmission;
Means for controlling the operation of the mobile node to avoid interference with the primary user when the determining means determines that the mobile node that transmitted the initial message senses primary user transmission; A master node is provided.

  In one embodiment, the master node further comprises means for storing a reserved preamble indicative of sensing of a primary user transmission, wherein the means for processing includes storing the preamble included in a received initial message. If the received preamble matches the reserved preamble, the mobile node that transmitted the initial message senses a primary user transmission. It is determined that

  In one embodiment, the master node further comprises means for transmitting a reserved preamble of the plurality of mobile nodes stored as part of system information.

  In one embodiment, when the control means responds to means for determining that the mobile node that sent the initial message is sensing a primary user transmission, in the allowed operating band, another mobile Arranged to stop sending to the terminal.

  In one embodiment, the master node further comprises means for transmitting an uplink resource allocation message to the mobile node that has sensed the primary user transmission.

  In one embodiment, the master node is operative to receive the sensed primary user transmission signal strength magnitude from the mobile node, and the control means is responsive to the received signal strength magnitude. It acts to determine again the control action for each mobile node.

  The present invention also provides a communication system including a plurality of mobile nodes and any one of the above-described master nodes.

The present invention is also a method performed by a master node communicating with a plurality of mobile nodes in an operating band allowed for a primary user device,
Receiving from the at least one mobile node primary user transmission information indicating signal strength of the primary user transmission received at the at least one mobile node;
Obtaining location information for each of the at least one mobile node;
Evaluating an area where duplication of communication may occur between the master node and the primary user using the received primary user transmission information and the acquired location information,
Comparing the location of each mobile node with the evaluated areas where duplication of communication may occur,
In order to avoid interference with the primary user by a master node and a mobile node, a method for controlling the operation of the mobile node based on a comparison result is provided.

  In one embodiment, the information is received at a media access control, MAC, and control element.

The present invention is also a method performed by a master node communicating with a plurality of mobile nodes in an operating band allowed for a primary user device,
Receiving from the at least one mobile node primary user transmission information indicating signal strength of the primary user transmission received at the at least one mobile node;
Controlling the operation of the mobile node based on the primary user transmission information to avoid interference to the primary user by a master node and a mobile node;
The receiving step operates at the media access control, MAC, layer of the master node and provides a method including extracting primary user transmission information from the MAC layer frame.

The present invention is also a method performed by a mobile node communicating with a master node in an operating band allowed for a primary user device,
Senses the transmission of the primary user device,
Measuring the sensed signal strength of the primary user transmission,
Reporting the magnitude of the measured signal strength to the master node;
The reporting step provides a method comprising reporting the magnitude of the measured signal strength in a media access control, MAC, layer frame for processing by a MAC entity of the master node.

The present invention is also a method performed by a mobile node communicating with a master node in an operating band allowed for a primary user device,
Receiving uplink resource allocation data designating uplink resources that the sensor node can use for data transmission to the master node;
Sensing the transmission of the primary user device;
Reporting the measured signal strength magnitude to the master node using uplink resources allocated by the master node;
In the sensing step, when the sensor node is not assigned an uplink resource, the reporting step comprises requesting an uplink resource assignment from the master node.

  In one embodiment, as part of a random access procedure, includes reporting a sensed primary user transmission in a message transmitted by the sensor node. The message may be an uplink request message of a random access procedure and may include a reserved preamble that notifies the master node of detection of primary user transmission in the allowed operating band.

  In one embodiment, the reporting step is part of a random access means.

  In one embodiment, the magnitude of the determined signal strength is reported in a MAC control element. After the sensor node further sends a message as part of the random access procedure and is given uplink resources to the sensor node, the magnitude of the measured signal strength may be reported.

The present invention is also a method performed by a master node communicating with a plurality of mobile nodes in an operating band allowed for a primary user device,
Receiving from the at least one mobile node primary user transmission information indicating signal strength of the primary user transmission received at the at least one mobile node;
Controlling the operation of the mobile node based on the temporary transmission user information to avoid interference to the primary user by a master node and a mobile node;
The receiving provides a method comprising receiving the primary user transmission information in a message transmitted by the at least one mobile node as part of a random access procedure.

  In one embodiment, the method further comprises receiving a notification of the transmitted primary user transmission in an uplink request message transmitted by the sensor node as part of a random access procedure. The uplink request message may include a reserved preamble that notifies the master node of detection of primary user transmission in the permitted operating band.

  In one embodiment, controlling the operation controls operation of the plurality of mobile nodes in response to receiving an uplink request message to the primary user by the master node and the mobile node. Including avoiding interference.

  In one embodiment, the primary user transmission information is received in a MAC control element.

The present invention is also a method performed by a master node communicating with a plurality of mobile nodes in an operating band allowed for a primary user device,
Receiving an initial message of a random access procedure from at least one mobile node;
Processing the received initial message to determine whether the mobile node that transmitted the initial message senses a primary user transmission;
If it is determined that the mobile node that transmitted the initial message senses a primary user transmission, the method includes controlling the operation of the mobile node to avoid interference with the primary user.

In one embodiment, the method stores a reserved preamble indicating sensing of a primary user transmission at the master node;
Determining whether the preamble included in the received initial message matches the reserved preamble stored;
If the received preamble matches the reserved preamble, the mobile node that has transmitted the initial message further determines that it senses a primary user transmission.

  In one embodiment, the method further comprises transmitting a stored reserved preamble as part of the system information to the plurality of mobile nodes.

  In one embodiment, controlling the operation is another mobile in the allowed operating band in response to determining that the mobile node that transmitted the initial message is sensing a primary user transmission. Controlling the master node to stop transmission to the terminal.

  In one embodiment, an uplink resource allocation message may be provided to the mobile node that transmitted the initial message.

  In one embodiment, the method receives the magnitude of the identified primary user transmission signal strength from the mobile node and performs a control action on each mobile node according to the received signal strength magnitude. You may decide again.

The present invention is also a method performed by a sensor node that communicates with a master node in an operating band allowed for a primary user device,
Stores reserved preamble,
Sensing the transmission of the primary user device;
Reporting the sensed primary user transmission to the master node;
The means for reporting provides a method for reporting to the master node by storing and sending the reserved preamble in an initial message of a random access procedure.

  The reserved preamble may be pre-programmed at a sensor node or preferably receives the reserved preamble as part of a system information broadcast by the master node.

  In one embodiment, the method further comprises receiving an uplink resource assignment from the master node.

  In one embodiment, the method further comprises measuring a signal strength magnitude of the primary user transmission and sending the signal strength magnitude to the master node. The measured signal strength may be sent to the master node using the uplink resource allocation received from the master node.

  In one embodiment, the method further comprises randomly generating a preamble for use in a random access procedure. The randomly generated preamble is compared with the stored reserved preamble, and if the randomly generated preamble matches the reserved preamble stored, the random preamble Another preamble used in the access procedure may be randomly generated.

  The present invention relates to a related computer program or computer which executes, for all disclosed methods, a related terminal, the terminal itself (user terminal, master node, mobile node, or parts thereof) and a method of updating equipment. Providing program products.

  ADVANTAGE OF THE INVENTION According to this invention, the selective cooperation system which detects and reports the transmission characteristic of a primary user, and controls the transmission opportunity of a secondary user can be provided.

It is a figure which shows the overlap area which can generate | occur | produce the object area of a master node and a primary transmitter, and interference. It is a block diagram which shows the main structures of the sensor mobile terminal shown in FIG. It is a block diagram which shows the main structure of the master node shown in FIG. It is a flowchart which shows the cooperation detection procedure of Embodiment 1. 6 is a flowchart illustrating a process in which a master node determines an operation of a mobile terminal in order to reduce interference. It is a general-view figure of the protocol stack which the mobile terminal and master node which this invention performs use. It is a general-view figure of the lower layer of the protocol stack which the mobile terminal and master node which this invention performs use. It is a figure which shows the general view of the protocol data unit which this invention performs. It is a figure which shows the general view of the service data unit of the protocol data unit of FIG. 7A. FIG. 7B is an overview of control elements used in combination with the protocol data unit of FIG. 7A. 1 is a schematic diagram of signal transmission showing communication performed between a sensor mobile terminal and a master node according to an embodiment of the present invention.

An example of an embodiment of the present invention will be described with reference to the accompanying drawings.
Overview FIG. 1 is a schematic diagram showing a cognitive radio communication network 1, and includes a master node 3 and a plurality of mobile terminals 5 (reference numerals 5 a to 5 e) controlled by the master node 3 within an area 13.
The master node 3 and the mobile terminal 5 are secondary users in the frequency band (B) permitted to one or more primary users. The primary user usually has a broadband primary transmitter 4 and a primary user equipment 7. The broadband primary transmitter 4 transmits in all or part of the permitted frequency band (B), and the primary user equipment 7 (reference numerals 7a-7c) transmits signals on different channels in the permitted band (B). Send or receive. For example, if the permitted band (B) corresponds to a television station channel (DVB-T operated with a 6 MHz or 8 MHz channel), the primary user equipment 7 receives a signal transmitted in all or part of the permitted band. During this time, the broadband primary transmitter 4 transmits on a number of channels. Some primary user equipment 7, such as PMSE (Programming Special Event) devices, can transmit in larger subbands (eg, 200 KHz or 400 KHz subbands) than 6 MHz or 8 MHz television station channels.

  Transmission of the mobile terminal 5 is controlled by the master node 3. While the primary user is not transmitting in all or part of the frequency band (B), or as long as the primary user is allowed to interfere with the transmission of the secondary user, the secondary user is in the frequency band (B) Can communicate in whole or in part. Usually, the arrangement of the master node 3 is fixed, and the mobile terminal 5 is movable. In a preferred embodiment, the master node 3 is a mobile phone base station and operates according to the Long Term Evolution (LTE) standard, and the mobile terminal 5 is an LTE user equipment, such as a mobile phone.

  Some or all of the mobile terminals 5 are arranged to operate as sensor nodes (hereinafter referred to as sensor mobile terminals 5) capable of sensing primary user transmissions within the permitted frequency band (B). . When the sensor mobile terminal senses primary user transmission, it is notified to the master node 3, and the master node 3 determines whether transmission by the secondary user is allowed in any of the permitted bands (B).

  As will be described in more detail below, various data and control information are transmitted between the master node 3 and the mobile terminal 5 in a number of frequency bands including the frequency band (B) permitted for the primary user. Yes. Furthermore, since the mobile terminal 5 can move in the area 13 controlled by the master node 3, the master node 3 records the position of the mobile end 5 either continuously, periodically, or occasionally. Thus, continuation of communication between the master node 3 and the mobile terminal 5 is ensured. When the mobile terminal 5 leaves the area 13 controlled by the master node 3, the transmission of data and control information is taken over to another master node (not shown) that can continue the transmission of data and control information with the mobile terminal 5. The handover may be started when the mobile terminal 5 still exists in the area 13 controlled by the master node 3 for reasons well known to those skilled in the art.

  While the master node 3 is set to a fixed position, it can be measured at a single location, and the sensor mobile terminal supplies its own current position measurement to move in the area 13 controlled by the master node 3 be able to. The sensor mobile terminal 5 may approach the primary transmitters 4, 7 from the master node 3, and thus may detect and measure more accurate primary user transmissions. When the sensor mobile terminal 5 performs detection, the detection and signal measurement are reported in a signaling message transmitted to the master node 3. The master node 3 uses the measurements from the different sensor mobile terminals 5 and the position information of these sensor mobile terminals 5, and there is a possibility of interference between the primary user and the secondary user in the permitted band (B). Define an area. The area with such a possibility of interference includes an overlapping area between the target area (cell) 13 controlled by the master node 3 and the target area 14 of the primary transmitter 4. The sub-area 19 with the possibility of interference will also be present with the transmission area 15a of the mobile terminal 5a overlapping the target area 14 of the primary transmitter 4. The size of the area 17 is largely determined by the transmission characteristics of the master node 3 and the primary transmitter 4, and the size of the sub-area 19 is mainly based on the location and the transmission characteristics of the mobile terminal 5 a and the primary transmitter 4.

  Initially, the primary transmitter 4 does not transmit in the permitted band (B). Therefore, there is no overlapping area 17 and the master node 3 can control all the mobile terminals 5 operating in the cell 13 to operate in the permitted frequency band (B). However, when the primary transmitter 4 starts transmission in the frequency band (B), the sensor mobile terminals 5b and 5c detect this transmission and sense the strength of the primary user signal. Then, the sensor mobile terminals 5b and 5c transmit to the master node 3 a report that notifies the master node of the detected primary user transmission and the transmission intensity thereof. In response, the master node 3 instructs the sensor mobile terminals 5b and 5c to stop transmission in the frequency band (B), and allocates a new frequency band to be transmitted continuously with the sensor mobile terminals 5b and 5c. The master node 3 analyzes the approximate location of the primary transmitter 4 using the reported signal strength and the location of the sensor mobile terminals 5b, 5c, and then analyzes the target area 14 and the overlap area 17. From this information, the master node 3 determines how much it needs to reduce its transmission power in the allowed band (B) in order to avoid transmission interference with the primary user in the target area 14. Can do. FIG. 1 shows a reduced size cell 13 ′ provided by the master node 3 in the frequency band (B) while avoiding interference with the primary user 4.

  Changing the size of the cell 13 affects other mobile terminals 5 managed by the master node 3. For example, the mobile terminal 5e is out of the range of the cell 13, and communication using the permitted band (B) cannot be performed. If the master node 3 operates another cell having a different operating frequency, the mobile terminal 5e is taken over to another cell. Otherwise, the mobile terminal 5e must be taken over to the adjacent master node 3.

  Similarly, some mobile terminals 5 are located outside the target area 14 of the primary user, but these transmissions can reach the target area. This is indicated by the fact that the transmission distance (indicated by area 15 a) of the mobile terminal 5 a overlaps with the target area 14 included in the sub-area 19. Therefore, transmission by the mobile terminal 5a may adversely affect the primary user 7a in the subarea 19. The master node 3 uses information from different sensor mobile terminals to measure which mobile terminal 5 falls into this category and indicates either a reduction in transmission power or a handover to another cell operating at a different frequency To do.

  In a preferred embodiment, other mobile terminals 5 (eg, mobile terminal 5d) that are located in the reduced cell 13 'and are far away from the target area 14 of the primary user 4 are such that the master node 3 Although the mobile terminal 5d is monitored, it is possible to continue using the permitted frequency band (B). When the mobile terminal 5d moves to the target area 14, the master node 3 instructs the mobile terminal 5d to reduce the transmission power, or hands over the mobile terminal 5d to another cell that operates at a different frequency.

  As will be appreciated by those skilled in the art, the master node 3 should identify the mobile terminals 5 that will be affected by the appearance of the primary transmitter 4 and will determine the transmission power of itself in the allowed band (B) for each. Necessary control actions should be performed before reduction.

  A necessary control operation for some mobile terminals 5 is to stop transmission in the permitted band (B), and a necessary control operation for other mobile terminals 5 is transmission power in the permitted band (B). The control operation necessary for the other mobile terminal 5 is to hand over to another cell operating at a different frequency.

  In the present embodiment, the sensor mobile terminal 5 that detects the appearance of the primary transmitter in the permitted band (B) measures the primary transmission power and sends an indication to the master node 3. Then, after confirming that the display is correctly received by the master node 3, communication in the permitted band (B) is stopped. The reception of the indication is confirmed by the master node 3 sending a confirmation message using the hybrid automatic retransmission request (HARQ) technology of the radio interface in the LTE network.

Sensor Mobile Terminal FIG. 2 is a block diagram showing the main configuration of the sensor mobile terminal 5 shown in FIG. As shown in the figure, the mobile terminal 5 includes a transceiver circuit 223 that functions to transmit and receive transmission signals to and from other nodes (for example, the master node 3) via one or more antennas 225. The controller 227 controls the operation of the transceiver circuit 223 according to software stored in the memory 237. In addition, the mobile terminal 5 includes a user interface 229 that is controlled by the controller 227 and allows the user to exchange information with the communication device. The software stored in the memory 237 includes an operating system 239, a communication module 241, a positioning module 243, a sensor module 245, a measurement module 246, a report module 247, and a transmission frequency control module 249, among others.

  The operating system 239 controls the operation of the mobile terminal 5. The communication module 241 controls communication between the mobile terminal 5 and an external device via the transceiver circuit 223 and the antenna 225. The positioning module 243 serves to measure the position information of the sensor mobile terminal 5. The positioning module 243 may be a GPS or similar communication satellite or terrestrial position measurement module. The positioning module 243 sends regular position updates to the master node 3 either on demand or at predetermined intervals. The sensor module 245 serves to sense transmissions made by the primary user. The sensor module 245 can typically sense primary user transmissions within the entire permitted band (B) (and possibly other frequency bands as well). Whenever the sensor module 245 detects a primary user transmission, the measurement module 246 measures the magnitude of the primary user's transmission power, eg, the strength of the electromagnetic signal in the operating frequency band (B). The result from the measurement module 246 is returned to the master node 3 by the report module 247. Finally, the transmission frequency control module 249 transmits from the master node 3 identifying whether there is any band within the allowed band (B) that can transmit a piggyback signal without interfering with the primary user. Information is received and the transceiver circuit 223 serves to control the transmission frequency for such piggybacking transmissions.

Master Node FIG. 3 is a block diagram showing the main configuration of the master node shown in FIG. As shown in the figure, the master node 3 includes a transceiver circuit 323 that transmits and receives signals to and from other nodes via one or more antennas 325. The controller 327 controls the operation of the transceiver circuit 323 according to software stored in the memory 337. Further, the controller 327 can communicate with other communication devices via the network interface 329. The software stored in the memory 337 includes an operating system 339, a communication module 341, a positioning module 342, a mapping module 343, a frequency band assignment module 345, a result analysis determination module 347, and a secondary user control module 349, among others.

  The operating system 339 controls the operation of the master node 3. The communication module 341 communicates that the master node 3 communicates with the mobile terminal 5 via the transceiver circuit 323 and the antenna 325, and others via the network interface 329 (which may be a copper or fiber optic interface). Functionality to enable communication with other network devices and nodes. The positioning module 342 determines whether the master node 3 has received the position of the different mobile terminals 5 including the sensor mobile terminal 5 from the mobile terminal 5 or by a plurality of network nodes (eg, the master node 3). It can be measured by either triangulation sent to or received from. The frequency band allocation module 345 functions to allocate a frequency band that can be used to the mobile terminal 5 in the cell 13 controlled by the master node 3. The result analysis determination module 347 receives the sensing results returned from the different sensor mobile terminals 5, analyzes the results, and for the primary user currently operating in any part of the allowed frequency band (B). Each mobile terminal 5 or the master node 3 itself serves to determine whether or not interference occurs. The secondary user control module 349 determines when to start and stop using the frequency band assigned to each secondary user, or when a handover to another frequency band is required, or interference with the primary user. It works to notify you to change the transmission power to avoid.

  In the above, for ease of understanding, the master node 4 and the mobile terminal 5 are described as having a large number of individual modules (eg, communication module, positioning module, sensor module, report module, etc.). While these modules are supplied to a particular application in the manner described above, for example, a system in which features of the invention are designed from the beginning if a system that exists in another application is modified to perform the invention As an example, these modules would be built into the entire operating system or code, and these modules would not be recognized as separate elements.

Master Node Control Several new aspects of the operation of the master node 3 and the sensor mobile terminal 5 will be described in more detail.

  FIG. 4 is a flowchart showing the entire operation of the master node 3. As shown in the figure, in step s41, the communication module 341 of the master node 3 receives information indicating the signal strength of the primary user transmission received by one or more sensor mobile terminals 5 from one or more sensor mobile terminals 5.

  In step s43, the positioning module 342 acquires position information regarding the mobile terminal 5.

  In step s45, the mapping module 343 detects the area 17 in which duplication of communication may occur between the master node 3 and the primary user 4, the received primary user transmission information, and the acquired mobile terminal 4 that has detected the primary user 4. Evaluate using location information about.

  In step s47, the result analysis determination module 347 of the master node 3 compares the position of each mobile node 5 currently managed by the master node 3 with the area 17 where duplication of evaluated communication may occur.

  Finally, in step s49, the secondary user control module 349 of the master node 3 controls the operation of the mobile node 5 based on the comparison result in order to avoid interference with the primary user 4 by the master node 3 and the mobile node 5. .

  FIG. 5 is a diagram illustrating a process executed by the result analysis determination module 347 for each mobile terminal 5 managed in the area 13 controlled by the master node 3 in step s47.

  In step s50, the result analysis determination module 347 confirms whether the mobile terminal 5 currently under consideration is currently operating in the permitted frequency band (B). In step S51, when the mobile terminal 5 is not currently operating in the band (B), the result analysis determination module 347 starts using the frequency band B (without causing interference). It is determined whether or not it is a candidate. If this analysis is a positive result, in step s52, the result analysis determination module 347 permits the candidate terminal 5 to start transmission in the band (B) permitted. If the analysis in step S51 is a negative result, in step 57, the result analysis determination module 347 concludes that it is not necessary to change the operation of the candidate mobile terminal 5. After step s52 or step s57, the result analysis determination module 347 ends the examination for the current mobile terminal 5 and starts the examination for the next mobile terminal 5.

  If it is determined in step s50 that the current terminal 5 is operating in the frequency band (B), the result analysis determination module 347 proceeds to step 53, and determines whether or not the mobile terminal 5 exists in the evaluated interference area 17. Make sure. When the mobile terminal 5 does not exist in the area 17, the result analysis determination module 347 confirms whether or not the transmission area 15a of the mobile terminal overlaps the target area 14 of the primary transmitter 4 in step s54. If not, the result analysis determination module 347 concludes that it is not necessary to change the operation of the current mobile terminal 5 in step s57, and the result analysis determination module 347 starts to consider the next mobile terminal 5. . However, if it is determined in step s54 that there is an overlap, the result analysis determination module 347 proceeds to step s56 and determines to limit the transmission power of the mobile terminal 5 in order to avoid interference. The amount by which the mobile terminal limits the transmission power depends on how close it is to the primary transmitter area. Thereafter, the result analysis determination module 347 proceeds to step s58.

  In step s53, for the mobile terminal 5 existing in the interfering area 17, the result analysis determining module 347 proceeds to step s55, and permits the current mobile terminal 5 to transmit in the permitted frequency band (B). It determines that there is not, and proceeds to step s58.

  In step s58, the result analysis determination module 347 requires a handover for a mobile terminal that is permitted to transmit only with limited power and a mobile terminal that is not permitted to transmit in all permitted bands (B). (Or is really possible). If the handover is not necessary (or is not possible), the result analysis determination module 347 terminates the processing of the current mobile terminal 5, otherwise, the determined handover is first performed in step s59.

  In the present embodiment, the above-described steps are performed for all mobile terminals managed by the master node 3, but are performed for at least the mobile terminal 5 that may cause interference to the primary user. The decision for each mobile terminal 5 is communicated to each mobile terminal 5 as described in connection with the master node 3 and the secondary user control module 349 of FIG.

MAC signaling For example, communication between devices of the communication system such as the mobile terminal 5 and the master node 3 is performed according to a standard procedure. The open system interconnection reference model (OSI reference model) uses a seven-layer protocol stack to represent the flow of data in a network from one computer to another. As shown in FIG. 6A, these logical layers are divided into the physical layer (layer 1), data link layer (layer 2), network layer (layer 3), transport layer (layer 4) a session layer (layer 5), a presentation layer (layer 6), and an application layer (layer 7).

  Each logical layer has a separate function and operates a unique data format. When data flows from the upper layer to the lower layer, the data is converted into a lower layer data format and a lower layer header is added. This process is called encapsulation. On the other hand, when data flows from the lower layer to the upper layer, the data is converted into the data format of the upper layer, and the lower layer header is discarded.

  The physical layer (layer 1) identifies the physical and electrical characteristics of the network and manipulates information transmission over communication media (eg, cables and wireless links).

  The data link layer (layer 2) is the lowest layer in the OSI model that is related to addressing, specifically addressing to attach a specific destination to information. The data link layer is responsible for finally encapsulating higher level messages into frames that are transmitted over the network at the physical layer.

  The network layer (layer 3) is responsible for routing and addressing, and sending data packets to the destination within the allowed time.

  The transport layer (Layer 4) is responsible for end-to-end transport between end users. This layer provides buffering, ordering, flow control, and error detection to ensure that data is received in the correct order and without errors.

  The session layer (layer 5), presentation layer (layer 6), and application layer (layer 7) are often considered higher layers. These layers handle user connections and data formats. In most network technologies, the differences between these three layers are unclear and these functions are often handled by a single protocol.

  Details of the data link layer (layer 2) will be described with reference to FIG. 6B. Data link protocols improve service to higher layers by increasing reliability, security, and integrity. In addition, the data link layer is responsible for media access and scheduling. In the LTE system, due to its complicated functions, layers are further divided such as a media access control (MAC) layer, a packet data convergence protocol (PDCP) layer, and a radio link control (RLC) layer. The MAC layer is the lowest part, is close to the physical layer (layer 1), and takes charge of access control to the physical medium. The PDCP layer is primarily responsible for IP header compression and encryption, and in the case of handover, supports lossless mobility and provides integrity protection to higher layer control protocols. The RLC layer mainly consists of an automatic repeat request (ARQ) function and supports data division and concatenation.

  In the LTE system, the radio resource control (RRC) protocol is the main control function in the master node 3, and the installation of the radio bearer and all lower layers using RRC signaling between the master node 3 and the mobile terminal 5 Responsible for configuration. RRC layer (layer 3), for example, broadcasting system information; paging; setting, maintaining and releasing RRC connection between mobile terminal 5 and master node 3; protection function including key management; setting radio bearer Perform a number of services and functions such as mobility functions, quality of service management, mobile terminal measurement reporting and reporting control.

  As shown in FIGS. 6A and 6B, when a message is transmitted between two devices, it is transmitted to the lower layer through the protocol stack and transmitted by the lowest layer, and on the receiving side, the message is transmitted to the receiving terminal. It is transmitted to the equivalent layer. The message route is indicated by the arrow in FIG. 6A. For example, in the LTE system, the layer 3 message is created on the RRC layer and is transmitted by the PDCP layer, the RLC layer, the MAC layer, and the physical layer that operates the substantial transmission between the mobile terminal 5 and the master node 3. Processed (and vice versa). When sent to the receiver, the message is again processed first by the MAC layer, then by the RLC and PDCP layers, and finally delivered to the working RRC layer. Even though the logical structure of the layer protocol stack ensures that each function is performed on the most appropriate layer, in an interference situation, the layered architecture is in the handling of information about the emergence of the primary transmitter 4. It is possible to introduce unnecessary delays. Therefore, as will be described in detail below, in order to inform the master node of the primary user transmission as soon as possible, the sensor node transmits control data indicating that the primary user transmission has been sensed to the MAC rather than the commonly used upper layer. It is configured to transmit at the layer.

  As described above, when the sensor mobile terminal 5 detects the transmission of the primary transmitter 4, the sensor mobile terminal 5 measures the reception power of the primary user signal, and receives the detected transmission and the sensor node to the master node 3. The strength of the primary user signal is notified. In this embodiment, the measured transmission power is reported to the master node 3 in a MAC layer signaling message that is processed and operated by the MAC layer of the master node 3.

  FIG. 7A shows a MAC protocol data unit 71 (PDU) used in this embodiment. The MAC PDU 71 is generally known as a frame and is a unit of information delivered between data link layer (layer 2) devices. The main part of the MAC PDU 71 is a header 72 including a frame control field 73, a sequence number field 74, and an address field 75 (some of these elements may be referred to as subheaders). The header element defines the characteristics of the MAC PDU 71 related to the transmission, such as sender / recipient, control parameters, frame order of sequence units, quality of service, whether the content is retransmitted, etc. The MAC service data unit 76 (SDU) includes data that is intended for processing by higher layers (eg, RLC, PDCP, and RRC layers). The last of the MAC PDU 71 is an error detection code 79, which is a normal cyclic redundancy code (CRC).

  In a similar manner, the MAC layer SDU 76 can constitute the upper layer PDU 171. However, if the upper layer PDU 171 is not compatible with the MAC SDU 76, it can be divided into several consecutive MAC SDUs 76, and this technique is known as segmentation. When all the segmentations of the upper layer PDU 171 are received by the upper layer, they are processed by the upper layer or further transferred to the upper layer. Therefore, the content of the upper layer PDU 171 is processed relatively slowly as compared with the header 72 of the MAC PDU 71.

  As shown in FIG. 7B, the upper layer PDU 171 includes a frame control field 173, a sequence number field 174, an address field 175, an SDU 176 for other layers, and an error detection code 179.

  The payload 78 is used as a term representing the portion of the MAC PDU 71 after the header 72. Not all of the payload 78 is always for higher layers. The frame control field 73 indicates that the payload 78 includes one or more MAC control elements 77 to be provided to the MAC layer itself, and such control elements 77 are not transferred to the upper layer. Not all of the multiple MAC PDUs 71 include a control element 77, and different MAC PDUs 76 include different control elements 77 that are not normally associated with MAC SDUs 76 that carry higher layers.

  The control element 77 is always inserted in the first part of the MAC SDU 76 and is inserted before any part of the upper layer PDU 171. This priority ensures that the control element 77 is processed before any higher layer data to be delivered. Therefore, any information contained therein is processed earlier by the master node 3 than normal higher layer signaling messages, such as radio resource control (RRC) messages. In the present embodiment, the plurality of sensor mobile terminals 5 include the magnitude of received power in the control element 77 of the MAC signaling message (MAC PDU 71) sent from the sensor mobile terminal 5 to the master node 3. Such a control element 77 is added to one of the MAC frames 71 and transmitted without delay time.

  After the area 17 where interference can occur is defined, the master node 3 transmits a MAC signaling message including the magnitude of the received power to the appropriate control element 77 of the MAC PDU 71 to each mobile terminal 5 causing the interference. In this method, the master node 3 can notify all the mobile terminals 5 that need to stop transmission in the permitted band (B).

  In order to improve the notification at the MAC layer, a new concrete control element 77 is required in the uplink (notification from the plurality of sensor mobile terminals 5 to the master node 3) and another one in the downlink (master node 3 to the mobile terminal). One possible format for these two new MAC control elements is shown in FIG. 7C.

  The MAC control element 77 has a fixed size and is composed of the following 8 bits. The first two bits b1 and b2 are reserved bits and are set to “0” or “R” in this case. The remaining bits b3 to b8 contain a binary value related to the primary received power (the primary received power is the signal level or power of the detected primary user transmission measured by the sensor mobile terminal 5).

  The presence of a control element 77 in the payload 78 is indicated by data in the frame control field 73. In the LTE system, this frame control field data is defined by a logical channel ID (LCID) field. In order to introduce a new MAC control element 77, it is necessary to define a new logical channel ID that identifies two new types of control elements 77. LCID values that can be used for uplink and downlink shown in the following table can be set.

  Whenever an appropriate LCID is used in the MAC PDU 71 transmitted between the sensor mobile terminal 5 and the master node 3, the recipient has the MAC control element 77 present in the data link layer (MAC layer). Know what will be processed. For example, the magnitude of the primary transmission power from the control element 77 is extracted from the MAC control element 77 at the MAC layer and used as an input to the result analysis determination module 347 of the master node 3.

In the LTE system, a plurality of mobile terminals 5 or sensor mobile terminals 5 need to be allocated uplink resources of nodes that can transmit uplink data (including the MAC signaling message described above). Therefore, the allocation of these uplink resources affects the ability of the mobile terminal 5 to transmit measurement reports. There are three situations to consider.
i) The mobile terminal 5 is allocated sufficient uplink resources to meet the current data transmission requirements.
ii) The mobile terminal 5 is allocated some uplink resources but does not meet the current data transmission requirements.
iii) The mobile terminal 5 has not been assigned any uplink resources due to lack of data to transmit on the uplink or for other reasons such as temporarily overloading the LTE system.

  Multiple sensor mobile terminals 5 with several assigned uplink resources (situation i or ii) can notify the master node 3 as soon as it detects the appearance of a primary user 4 using the assigned resource . However, the sensor mobile terminal 5 that does not actively transmit data to the master node 3 does not have an allowed uplink resource and cannot immediately transmit information on the detected reception power of the primary user transmission. In the absence of dedicated uplink resources, such sensor mobile terminals 5 are configured to transmit this information on a common channel or signaling channel. When such a channel cannot be used, such a sensor mobile terminal 5 starts setting a new data connection to the master node 3 in order to transmit information related to the reception power of the primary user transmission. In the LTE system, this is called a random access procedure, and a procedure for setting a new connection between the master node 3 and the mobile terminal 5 is shown in FIG.

  Since the physical layer (layer 1) supplies all the mobile terminals 5 within the cell 13, the procedure for starting communication in the uplink direction is executed as follows.

  In step s81, the sensor mobile terminal 5 requests an uplink resource. Uplink resources are controlled by the master node 3. The LTE system includes a random access preamble message, and the random access preamble message is generated in the MAC layer and transmitted to the master node 3 by the mobile terminal 5 through the random access channel.

  In step s83, the master node 3 notifies the sensor mobile terminal 5 of the uplink resource that has been successfully allocated, and the sensor mobile terminal 5 can start communication on the allocated channel. The LTE system includes a random access response message, and the random access response message is generated at the MAC layer by the master node 3 and includes a cell radio network temporary identifier (C-RNTI) that uniquely identifies the mobile terminal 5. Using the random access response message, the master node 3 informs the mobile terminal 5 about the exact timing advance value used in subsequent communications and allows the first resource for uplink communication.

  In step s85, the sensor mobile terminal 5 can notify the master node 3 about the appearance of the primary transmitter 4, and the mobile terminal 5 measures the primary user transmission detected by the MAC control element 77 as described above. Transmitting uplink data using the allocated resources, including the signal power allocated. In the LTE system, an RRC connection request message is provided, and the RRC connection request message is generated by the RRC layer. The uniqueness of the mobile terminal 5 (specification of the sender of the message) and the installation factor (specification of the reason for the uplink resource request) are specified. deliver. According to the present embodiment, the measurement result is inserted into this message as the MAC control element 77, and before the message is delivered to the RRC layer (layer 3) by the master node 3, or instead of delivery, the MAC layer (layer 2). ).

  In step s87, the master node 3 confirms receipt of the measurement result, and can control the operation of the mobile terminal 5 in the cell 13 by the above-described procedure.

  Increasing the overall load on the communication system increases the likelihood of interference to the primary user 4, but at the same time allowed many mobile terminals 5 to have no allocated resources. It is extremely difficult to notify the master node about the appearance of the primary user 4 in the frequency band (B). These mobile terminals 5 use the random access procedure of the above-described embodiment.

Advantageous Effects The above-described embodiment has many effects. Since the MAC control element 77 provides the master node 3 with an immediate and concise means for the appearance of the primary user 4, the time period for reporting and processing measurements is reduced.

  At the same time, since the master node 3 receives measurement reports from a large number of sensor mobile terminals 5 arranged closer to the primary user than the master node 3, the detection accuracy is improved.

  In order to avoid interference, only those mobile terminals 5 that are affected by the appearance of the primary user 4 need to move to different frequency bands, so the calculation of the area 17 of possible interference is the allowed frequency This contributes to better utilization of effective resources in the band (B).

  Regardless of the uplink resources permitted to the sensor mobile terminal 5, it is possible to transmit the measurement results using the same format, specifically, the MAC control element 77, and the design of the mobile terminal 4 and the master node 3 Reduce the complexity.

Variations and other possibilities The detailed embodiments have been described above. One skilled in the art can make many variations and other possibilities to the above-described embodiments to adapt while maintaining the effect of the invention. Some of these variations and other possibilities will be described with reference to the drawings.

  In the embodiments described above, the sensor mobile terminals that detect primary user transmissions are all secondary users, specifically, these are not only perceived in the allowed band (B) but also allowed band (B). Sent by. In other embodiments, one or more sensor mobile terminals may not be secondary users. Instead, they may simply sense within the allowed band (B) and report the sensing results.

  The term primary transmission may refer to a base station of a wireless communication network or any user base provided by a base station in a coverage area. The received power of the primary user transmission may not indicate an accurate measurement, for example, the sensor mobile terminal may derive from the evaluation or comparison level of the transmitted power, for example, various quantization techniques May be applied.

  In one embodiment of the invention implemented in the LTE system, the master node is usually formed by an LTE base station. In the LTE system, a large number of base stations are provided and can each operate as a master that controls a sensor mobile terminal (typically a user terminal, eg, a mobile phone) within a cell. Base stations work voluntarily to determine their location without communicating with the presence of the upper network in a manner that does not concentrate. Base stations cooperate with each other in exchanging information over the X2 interface and making decisions based on information received from neighboring base stations.

  While various aspects of the invention have been represented using the MAC protocol along with LTE systems, other systems and various lower layer protocols can be used as well. Although the use of control elements has been clarified, other parts of the MAC protocol (or other lower layer protocol) messages, such as headers, sub-headers, control elements, or payloads can also be used.

  Although various confirmation messages propose to confirm receipt of measurement results at the master node, in one embodiment, the sensor mobile terminal immediately uses the bandwidth granted to the primary, eg, such a confirmation message. Will be canceled before receiving. In other embodiments, the motion sensor mobile terminal using multiple frequency bands may be configured to notify a master node other than the band authorized for the primary. These changes will further reduce the occurrence of interference by secondary users.

  In the embodiment shown in FIG. 8, the sensor mobile terminal is configured to transmit a control element for primary user signal measurement (after uplink resources are granted) in a third message. In other embodiments, the sensor mobile terminal may include a control element in the first message of the uplink request procedure. On the other hand, in another embodiment, the sensor mobile terminal may employ a signaling message that is part of another procedure for transmitting the control element.

  In the embodiment shown in FIG. 8, the control element is transmitted by the sensor mobile terminal in a third message notifying the master node of the primary user transmission detected in the allowed frequency band (B), the control element being the primary user Providing transmission signal measurements to the master node.

  In another embodiment, the detected primary user transmission notification is sent from the sensor mobile terminal in the first message of the random access procedure (in other words, the initial message of the random access procedure used for the uplink resource request), and the primary user The signal measurement of the transmission is provided in a message following the random access procedure, eg a third message (in other words, when the sensor mobile terminal is uplinked and assigned a source by the master node and authorized).

  Unauthorized terminal to the master node, even though the uplink resource to communicate with the master node is not authorized, the unauthorized terminal (the mobile terminal is in connected mode and the master does not have the authorized uplink resource It will be very effective because it can be connected mode to connect to the node or the mobile terminal is in idle mode and not in communication with the master node can notify the appearance of the primary user.

  In this embodiment, the master node can select a subset of mobile terminals that act as sensor mobile terminals, and the sensor mobile terminal notifies the master node of detection of primary user transmission in the allowed frequency band (B). can do. Because a limited number of mobile terminals that operate as sensor mobile terminals are selected, attempts to simultaneously access the random access channel by a large number of mobile terminals can reduce the likelihood of random access channel overload.

  How to implement other possible embodiments in an LTE communication system will be described in more detail.

In the currently proposed LTE standard, a mobile terminal that is not allowed uplink resources requests a resource from a base station (master node) using a random access channel (RACH).
The mobile terminal can access the RACH using contention-based technology or non-contention-based technology.

  In the contention-based technology, each mobile terminal selects a random access communication opportunity and randomly selects (generates) a preamble to be included in an uplink request message to be transmitted to the master node. In response to receiving the uplink request message, the master node returns a message for allocating uplink resources to the mobile terminal. However, if two or more mobile terminals randomly select the same preamble and transmit to the same RACH at the same time, a collision will occur and the master node will not be able to receive the transmitted message due to the collision. Therefore, the master node is not aware of the up request message. If the mobile terminal is unable to receive the resource allocation message within the specified time, the mobile terminal assumes that the master node has not received an uplink request message and messages the next possible random access opportunity with higher transmit power. Will be resent.

  In non-contention based technology, the master node assigns a unique preamble to each mobile terminal. Random access communication opportunities are selected by each mobile terminal or assigned by the master node. Since the assigned preamble is unique to each mobile terminal, the mobile terminals can share usage at the same time without competing for RACH usage. RACH contention can be removed by assigning different mobile terminals different random access communication opportunities by the master node.

Contention-based embodiment In a mobile terminal embodiment that uses contention-based technology to access the RACH, the master node should have one sensor node that should use detection of primary user transmission to notify the master node. Allocate one reserved preamble signal. The reserved preamble includes system information broadcast from the master node to the mobile terminal.

  More specifically, a new specific field “Primary_detection_specific_incumbent” is defined in the system information in order to define a specific preamble (reserved preamble) to be used in notification of primary user transmission. This can be defined in the “RACH-ConfigCommon” information element of the “RadioResourceConfigCommon” element that presents System Information Blocks (SIBs) of the system information.

The “RACH-ConfigCommon” information element includes a “Primary_detection_specific_incumbent” element and has the following format.

  The definitions of most of the parameters of the system information block are described in TS 36.321 v10.4.0, the contents of which are incorporated herein for reference. The newly added parameter is a “Primary_detection_specific_incumbent_preamble” parameter.

  The “RACH-Config-Dedicated” information element is used in the master node, defines a dedicated random access parameter for each mobile terminal, and has the following format.

“Ra-PreambleIndex” defines a reserved preamble used by the mobile terminal. Since LTE mobile devices use a dedicated preamble during the handover procedure, this table is already defined in TS36.321. Specifically, during LTE handover, the mobile device sends an RRC ConnectionReconfiguration message to the parameters required for handover (in other words, the new C-RNTI, the target eNB's security algorithm identifier, and any dedicated RACH preamble, Receiving from the source eNB (base station) together with the target eNB SIBs, etc., and performing access to the target cell via the RACH following the handover and non-conflicting procedures using a unique RACH preamble by the source eNB. Instructed.
This unique preamble is defined in the RACH-Config-Dedicated table described above. In this embodiment, in this way, the master node reuses the RACH configuration parameters and broadcasts a reserved preamble used to notify the master node of the appearance of the primary user.

  “Ra-PRACH-MaskIndex” is an index that restricts when the master node can transmit a random preamble by the mobile terminal.

  In the present embodiment, the master node and the selected plurality of sensor mobile terminals store a specific reserved preamble in a memory. Thus, when a primary user transmission is detected by the mobile terminal, the mobile terminal transmits an uplink request message including a reserved preamble to the master node. If the mobile terminal does not receive a confirmation from the master node indicating receipt of the uplink message within a predetermined period, the mobile terminal retransmits the uplink request message with higher transmission power.

  When the master node receives and decodes the uplink request message, it compares the received preamble with the reserved preamble stored in memory. If the received preamble matches the stored reserved preamble to notify detection of primary user transmission, the master node immediately measures the primary user signal level from the sensor mobile terminal that issues the notification. While waiting for reception, the allocation of uplink resources to other mobile terminals in the permitted frequency band (B) is stopped, and interference with primary user transmission in the permitted frequency band (B) is avoided.

  To enable the sensing mobile terminal to report the measured primary user signal level to the master node, the master node responds to the initial RACH message by sending a resource allocation message to the sensor mobile terminal. The resource allocated by the master node is generally a frequency band other than the permitted frequency band (B), but if desired, it is within the permitted frequency band (B).

  After the uplink resources are allocated, the sensor mobile terminal transmits a message including the primary user signal measurement to the master node, initializes a timer, and responds to the response from the master node within a period predetermined by the timer. Start monitoring the physical downlink control channel (PDCCH).

  In response to receiving the primary user signal measurement, the master node returns a contention resource message to the sensor mobile terminal. The contention resource message indicates confirmation of the received primary user signal measurement to the sensor mobile terminal. If the master node does not receive the primary user signal measurement within a predetermined period, the master node can resume the allocation of uplink resources to the mobile terminal in the allowed frequency band (B).

  If the sensor mobile terminal does not receive the contention resource message in a predetermined period, it is assumed that the master node has not received the transmitted primary user measurement, and a notification to transmit the reserved preamble to the master node by another RACH Start the process again. However, if the contention resource message is received within a predetermined period, the sensor mobile terminal stops transmission in the permitted frequency band (B) (when not stopped).

  Similar to sending the contention resource message to the sensor mobile terminal in response to receiving the primary user signal measurement, the master node selectively selects the frequency band to which each mobile terminal is allowed based on the received primary user measurement. Control to operate in (B) is started. This has been described with reference to FIG. 4 and is specifically as follows.

  Based on received primary user transmission signal measurements, the master node determines that transmission of the mobile terminal in the allowed frequency band (B) may cause interference to the primary user (eg, When the mobile terminal is within the communication range of the primary user), the master node controls the mobile terminal to stop communication in the permitted frequency band (B). In this case, the master node adjusts so that the mobile terminal is taken over to another frequency band. For example, if the allowed band is a television channel, the master node places the selected mobile terminal on another television channel. In this scheme, the selected mobile terminal feels that the service with the master node continues while the primary user is allowed to use the permitted frequency band (B).

  Based on the received primary user transmission signal measurement, the master node may cause the mobile terminal transmission in the allowed frequency band (B) to cause interference to the primary user, but the mobile terminal When it is determined that interference does not occur when limiting the master node, the master node controls the mobile terminal to limit the transmission power in the permitted frequency band (B).

  If the master node determines that the mobile terminal is not likely to interfere with the primary user (eg, if the mobile terminal is outside the primary user's range), the mobile terminal is in the allowed frequency band (B) It is allowed to continue operation.

  Of course, when the mobile terminal cannot detect the primary user transmission, the mobile terminal may wish to establish a communication session with the master node using contention based RACH technology. As described above, the mobile terminal starts the RACH procedure using the randomly generated preamble. In order to avoid the primary user transmission being erroneously notified to the master node, the mobile terminal needs to check that the reserved preamble is not the same as the randomly generated preamble. If the randomly generated preamble matches the reserved preamble, the mobile terminal proceeds with a process of generating another preamble.

Non-contention based embodiment In an embodiment where the mobile device uses non-contention based techniques to notify the master node of the appearance of the primary user, the master node assigns two unique reserved preambles to each mobile terminal. One notifies the appearance of the primary user, and the other is used in the normal non-conflicting RACH procedure. This embodiment operates in the same way as the competing embodiment, except that different reserved preambles are assigned to each mobile terminal. The operation in this mode can be realized when there are few sensor terminals because the number of reserved preambles is limited.

  A further variation of the above embodiment uses a different part of the MAC PDU than the control element sending the primary user transmission information, for example an appropriate field of the header or subheader. Without departing from the spirit of the claims, these several fields are sent to the upper layer for processing.

  In the embodiment described above, the transmission power of some mobile terminals has been limited to avoid interference. Instead of limiting transmission power, or in addition to limiting transmission power, directional antennas can be used in mobile terminals (and master nodes), and the transmission direction of transmission signals is changed. There is a possibility of avoiding interference with the primary user. In this case, the master node and the mobile terminal can continue to use the permitted band by managing their own signals away from the primary transmission (between the outside of the target area).

  In the above-described embodiment, a large number of nodes are described. Those skilled in the art will interpret these nodes as comprising any type of communication node or device, including access points and user devices such as mobile phones, personal digital assistants, laptop computers, web browsers, etc. .

  In the embodiment described above, a number of software modules have been described. A person skilled in the art can interpret that the software module is of a compiler type or a non-compiler type and is supplied to the cognitive node by a signal via a computer network or a recording medium. In addition, some or all of the functions implemented by software are implemented using one or more dedicated hardware circuits. However, the use of software modules should facilitate node updates to update their functionality. Similarly, the embodiments described above use transceiver circuits, but at least some of the functionality of the transceiver circuits can be implemented in software.

  Various other modifications will be apparent to those skilled in the art and will not be described in detail here.

  For example, the present invention can be realized by a program that causes a CPU to execute the processing shown in FIGS.

  The program can be stored on various types of non-transitory computer readable media and provided to a computer. Non-transitory computer readable media include various types of tangible recording media. Examples of non-transitory computer-readable media are magnetic recording media (eg flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg magneto-optical discs), CD-ROMs, CD-Rs (recordable compact discs). ), CD-R / W (rewritable compact disc), semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory)). The program may also be supplied to the computer by various types of transitory computer readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The transitory computer readable medium can supply the program to the computer via a wired communication path (for example, an electric wire and an optical fiber) or a wireless communication path.

  This application claims priority based on UK Application No. 111457.6 filed on August 23, 2011 and UK Patent Application No. 1204041.6 filed on March 7, 2012; The entire disclosure is incorporated herein.

1 Wireless Communication Network 3 Master Node 4 Broadband Primary Transmitter (Main Transmitting Material)
5, 5A to 5E Mobile terminal 7, 7A to 7C Primary user device 14 Target area 19 Subarea 71, 171 MAC protocol data unit 223 Transceiver circuit 225 Antenna 227 Controller 229 User interface 237 Memory 239 Operating system 241 Communication module 243 Positioning module 245 sensor module 246 measurement module 247 report module 294 transmission frequency control module 323 transceiver circuit 325 antenna 327 controller 329 network interface 337 memory 339 operating system 341 communication module 342 positioning module 343 mapping module 345 frequency band allocation module 347 result analysis decision Module 349 secondary user control module

Claims (85)

A master node for use with multiple mobile nodes,
Receiving means for receiving, from the at least one mobile node, primary user transmission information indicating a signal strength of a primary user transmission received by the at least one mobile node;
Obtaining means for obtaining position information relating to each of the at least one mobile node;
An evaluation means for evaluating an area where duplication of communication may occur between the master node and the received primary user transmission information and the primary user, using the received primary user transmission information and the acquired position information;
A comparison means for comparing the position of each mobile node with the evaluated area where duplication of communication may occur;
A master node comprising: control means for controlling the operation of the mobile node based on a comparison result in order to avoid interference with the primary user by the master node and the mobile node.   The master node according to claim 1, wherein the receiving means is operative to receive information at a media access control, MAC, control element.   2. The master node according to claim 1, wherein the acquisition unit operates to acquire the position information regarding each of the at least one mobile node from the mobile node.   4. The master node according to claim 1, wherein the acquisition unit is configured to acquire the position information related to each of the at least one mobile node from communication with a positioning system or another master node. 5.   The control means includes: prevention of use of the primary user transmission band; execution of handover to a band different from the primary user transmission band; limitation of transmission power of the mobile node in the primary user transmission band; and 5. Acting to control the operation of the mobile node using at least one of the permissions for the mobile node to continue communication in the bandwidth of the primary user transmission. 6. Master node described in.   6. The control means according to claim 1, wherein the control means serves to control transmission power and / or a transmission direction of the master node in a band of the primary user transmission in order to avoid interference with the primary user. Master node described in.   The control means transmits the primary user transmission information in the MAC control element to the at least one mobile node in order to stop at least one mobile node of the plurality of mobile nodes from transmitting in the primary user transmission band. 7. A master node as claimed in any one of claims 1 to 6 which serves to send to a node. A sensor node used with a master node, wherein the sensor node and the master node can communicate with each other in an operating band allowed for a primary user device,
Sensing means for sensing transmission of the primary user device;
Measuring means for measuring the magnitude of the sensed signal intensity of the primary user transmission;
Reporting means for reporting the magnitude of the measured signal strength to the master node,
The reporting means is a sensor node operative to report the magnitude of the measured signal strength in media access control, MAC, layer frames for processing by the MAC entity of the master node.   9. The sensor node according to claim 8, wherein the reporting means serves to report the magnitude of the measured signal strength within the MAC control element.   10. The sensor node according to claim 8 or 9, wherein the reporting means serves to report a display of position information of the sensor node.   The sensor node according to any one of claims 8 to 10, wherein the sensor node serves to stop communication in the band of the primary user transmission.   12. The sensor node according to claim 11, which operates to stop communication in the primary user transmission band after the sensor node receives confirmation from the master node. A master node for use with multiple mobile nodes,
Receiving means for receiving, from the at least one mobile node, primary user transmission information indicating a signal strength of a primary user transmission received by the at least one mobile node;
Control means for controlling the operation of the mobile node based on the primary user transmission information to avoid interference to the primary user by the master node and the mobile node, and
The receiving means operates in the media access control, MAC, layer of the master node, and is arranged to extract primary user transmission information from the MAC layer frame.   The master node according to claim 13, wherein the receiving means is operative to receive the primary user transmission information within a MAC control element.   The master node according to claim 13 or 14, further comprising transmission means for sending an approval to the at least one mobile node and causing the at least one mobile node to stop transmission in the band of the primary user transmission.   Transmission means for sending the primary user transmission information to at least one of the plurality of mobile nodes within a MAC control element, and causing the at least one mobile node to stop transmission in the band of the primary user transmission The master node according to claim 13 or 14. A sensor node is used with a master node, and the sensor node and the master node communicate with each other in an operation band permitted for a primary user device,
Communication control means for receiving uplink resource allocation data for designating uplink resources that the sensor node can use for data transmission to the master node;
Sensing means for sensing transmission of the primary user device;
Reporting means for reporting the measured magnitude of signal strength to the master node using uplink resources allocated by the master node;
When the sensing node senses the primary user transmission when the sensor node is not assigned an uplink resource, the communication control means is arranged to request allocation of an uplink resource from the master node. Sensor node.   18. A sensor node according to claim 17, wherein the reporting means serves to report primary user transmission information, an indication of a sensed primary user transmission in a message transmitted by the sensor node as part of a random access procedure.   19. The sensor node according to claim 18, wherein the message is an uplink request message of a random access procedure and includes a reserved preamble that notifies the master node of detection of primary user transmission in the permitted operating band.   19. A sensor node according to claim 18, wherein the reporting means is operative to report primary user transmission information within a MAC control element.   The reporting means serves to report the measured signal strength magnitude after the sensor node further sends a message as part of a random access procedure and given uplink resources to the sensor node. The sensor node according to any one of 18 to 20. A master node for use with multiple mobile nodes,
Receiving means for receiving, from the at least one mobile node, primary user transmission information indicating a signal strength of a primary user transmission received by the at least one mobile node;
Control means for controlling the operation of the mobile node based on the temporary transmission user information in order to avoid interference with the primary user by a master node and a mobile node;
The receiving means is a master node arranged to receive the primary user transmission information in a message transmitted by the at least one mobile node as part of a random access procedure.   23. The master node of claim 22, wherein the receiving means is operative to receive a notification of a sensed primary user transmission in an uplink request message sent by the mobile node as part of a random access procedure.   The master node according to claim 23, comprising a reserved preamble for notifying the master node of detection of primary user transmission in the operating band in which the uplink request message is permitted.   The control means controls the master node and the plurality of mobile nodes in response to receiving an uplink request message including the reserved preamble, and the primary user by the master node and the mobile node. 25. A master node as claimed in claim 24, which serves to avoid interference with the master node.   23. A master node as claimed in claim 22, wherein the receiving means serves to receive the primary user transmission information within a MAC control element.   27. The receiving means operative to receive the primary user transmission information after a mobile node further sends a message as part of a random access procedure and is given uplink resources to the mobile node. The master node according to any one of the above. A sensor node is used with a master node, and the sensor node and the master node can communicate with each other in an operation band permitted for a primary user device,
Means for storing a reserved preamble;
Sensing means for sensing transmission of the primary user device;
Reporting means for reporting a sensed primary user transmission to the master node;
The reporting means serves to report to the master node by storing and transmitting the reserved preamble in an initial message of a random access procedure.   29. The sensor node according to claim 28, further comprising means for receiving the reserved preamble as part of a system information broadcast by the master node.   30. The sensor node of claim 28 or 29, wherein the sensor node further comprises means for receiving an uplink resource assignment from the master node. The sensor node measures the magnitude of the signal strength of the primary user transmission;
The sensor node according to any one of claims 28 to 30, further comprising means for sending the magnitude of the signal strength to the master node.   32. The sensor node according to claim 31, wherein the sensor node is arranged to send a measured signal strength to the master node using the uplink resource allocation received from the master node.   The sensor node according to any one of claims 28 to 32, further comprising means for randomly generating a preamble used in a random access procedure.   The sensor node operates to compare the randomly generated preamble with the stored reserved preamble, and the randomly generated preamble matches the stored reserved preamble. 34. The sensor node of claim 33, wherein if so, the sensor node serves to randomly generate another preamble for use in a random access procedure. A master node used with a plurality of mobile nodes, wherein the master node and the mobile node can communicate with each other in an operating band permitted for a primary user device;
Means for receiving an initial message of a random access procedure from at least one mobile node;
Means for processing the received initial message to determine whether the mobile node that transmitted the initial message senses a primary user transmission;
Means for controlling the operation of the mobile node to avoid interference with the primary user when the determining means determines that the mobile node that transmitted the initial message senses primary user transmission; A master node comprising: The master node further comprises means for storing a reserved preamble indicating a sense of primary user transmission;
The processing means determines whether the preamble included in the received initial message matches the reserved preamble stored, and the received preamble matches the reserved preamble. 36. The master node of claim 35, wherein the master node is arranged to determine that the mobile node that transmitted the initial message senses a primary user transmission.   The master node according to claim 36, further comprising means for transmitting the reserved preambles of the plurality of mobile nodes stored as part of system information.   When the control means responds to means for determining that the mobile node that sent the initial message senses a primary user transmission, the control means transmits to another mobile terminal in the permitted operating band. 38. A master node according to any one of claims 35 to 37 arranged to quit.   The master node according to any one of claims 35 to 38, further comprising means for transmitting an uplink resource allocation message to the mobile node that has sensed the primary user transmission. The master node serves to receive the sensed primary user transmission signal strength magnitude from the mobile node;
40. The master node according to any one of claims 35 to 39, wherein the control means serves to determine again a control operation for each mobile node according to the magnitude of the received signal strength. Multiple mobile nodes,
A communication system comprising: the master node according to any one of claims 1 to 7, 13 to 16, 22 to 27, and 35 to 40. A method performed by a master node that communicates with a plurality of mobile nodes in an operating band allowed for a primary user device,
Receiving from the at least one mobile node primary user transmission information indicating signal strength of the primary user transmission received at the at least one mobile node;
Obtaining location information for each of the at least one mobile node;
Evaluating an area where duplication of communication may occur between the master node and the primary user using the received primary user transmission information and the acquired location information,
Comparing the location of each mobile node with the evaluated areas where duplication of communication may occur,
A method for controlling operation of the mobile node based on a comparison result in order to avoid interference with the primary user by a master node and a mobile node.   43. The method of claim 42, wherein the information is received at a media access control, MAC, control element.   44. The method according to claim 42 or 43, wherein the obtaining step obtains the location information regarding each of the at least one mobile node from the mobile node.   44. A method according to claim 42 or 43, wherein the obtaining step obtains the location information for each of the at least one mobile node from communication with a positioning system or other master node.   The operation of the mobile node is controlled so as not to use the primary user transmission band, to hand over to a band different from the primary user transmission band, in the primary user transmission band, The operation of the mobile node is controlled using at least one of limiting the transmission power of the mobile node and allowing the mobile node to continue communication in the band of the primary user transmission. 46. A method according to any one of claims 42 to 45, which works as follows.   The said control step controls transmission power and / or the transmission direction of the said master node in the band of the said primary user transmission, in order to avoid the interference with the said primary user. the method of.   The controlling step includes transmitting the primary user transmission information in at least one MAC control element of the plurality of mobile nodes to cause the at least one mobile node to stop transmission in the band of the primary user transmission. 48. A method according to any one of claims 42 to 47 which serves to send. A method performed by a master node that communicates with a plurality of mobile nodes in an operating band allowed for a primary user device,
Receiving from the at least one mobile node primary user transmission information indicating signal strength of the primary user transmission received at the at least one mobile node;
Controlling the operation of the mobile node based on the primary user transmission information to avoid interference to the primary user by a master node and a mobile node;
The method of receiving comprises operating at a media access control, MAC, layer of a master node and extracting primary user transmission information from a MAC layer frame. 50. The method of claim 49, wherein the receiving step receives the primary user transmission information within a MAC control element.   51. The method of claim 49 or 50, further comprising: sending a confirmation to the at least one mobile node, causing the at least one mobile node to stop transmitting in the primary user transmission band.   Further comprising: sending the primary user transmission information to at least one of the plurality of mobile nodes within a MAC control element, causing the at least one mobile node to stop transmitting in the primary user transmission band. Item 49. The method according to Item 49 or 50. A method performed by a mobile node communicating with a master node in an operating band allowed for a primary user device, comprising:
Senses the transmission of the primary user device,
Measuring the sensed signal strength of the primary user transmission,
Reporting the magnitude of the measured signal strength to the master node;
The reporting step includes reporting the magnitude of the measured signal strength in a media access control, MAC, layer frame for processing by a MAC entity of the master node.   54. The method of claim 53, wherein the reporting step includes reporting a measured signal strength magnitude within a MAC control element.   55. A method according to claim 53 or 54, wherein the reporting step includes reporting an indication of the bandwidth of the primary user transmission.   56. A method according to any one of claims 53 to 55, wherein the reporting step includes reporting an indication of location information of the sensor node.   The method according to any one of claims 54 to 56, further comprising a mobile node that stops communication in a band of the primary user transmission.   58. The method of claim 57, wherein a confirmation is received from the master node prior to stopping communication in the primary user transmission band. A method performed by a mobile node communicating with a master node in an operating band allowed for a primary user device, comprising:
Receiving uplink resource allocation data designating uplink resources that the sensor node can use for data transmission to the master node;
Sensing the transmission of the primary user device;
Reporting the measured signal strength magnitude to the master node using uplink resources allocated by the master node;
In the sensing step, when the sensor node is not assigned an uplink resource, the reporting step comprises requesting an uplink resource assignment from the master node.   60. The method of claim 59, comprising reporting the sensed primary user transmission in a message transmitted by the sensor node as part of a random access procedure.   61. The method of claim 60, wherein the message is a random access procedure uplink request message and includes a reserved preamble notifying the master node of detection of primary user transmission in the allowed operating band.   60. The method of claim 59, wherein the reporting step is part of a random access means.   61. The method of claim 59 or 60, wherein the determined signal strength magnitude is reported in a MAC control element.   The reporting means reports the magnitude of the measured signal strength after the sensor node further sends a message as part of a random access procedure and is given uplink resources to the sensor node. 64. The method according to any one of 63. A method performed by a master node that communicates with a plurality of mobile nodes in an operating band allowed for a primary user device,
Receiving from the at least one mobile node primary user transmission information indicating signal strength of the primary user transmission received at the at least one mobile node;
Controlling the operation of the mobile node based on the temporary transmission user information to avoid interference to the primary user by a master node and a mobile node;
The method of receiving comprises receiving the primary user transmission information in a message transmitted by the at least one mobile node as part of a random access procedure.   66. The method of claim 65, operative to receive a notification of a transmitted primary user transmission in an uplink request message transmitted by the sensor node as part of a random access procedure.   68. The method of claim 66, wherein the uplink request message includes a reserved preamble that notifies a master node of detection of primary user transmission in the permitted operating band.   Controlling the operation controls the operation of the plurality of mobile nodes in response to receiving an uplink request message to avoid interference to the primary user by the master node and the mobile node. 68. The method of claim 67, comprising:   69. The method according to any one of claims 65 to 68, comprising receiving the primary user transmission information within a MAC control element.   MAC controlling the primary user transmission information to one of the plurality of mobile nodes to control the operation to cause the at least one mobile node to stop transmitting in the primary user transmission band. 69. A method according to any one of claims 65 to 68, comprising transmitting in the element. 35
A method performed by a master node that communicates with a plurality of mobile nodes in an operating band allowed for a primary user device,
Receiving an initial message of a random access procedure from at least one mobile node;
Processing the received initial message to determine whether the mobile node that transmitted the initial message senses a primary user transmission;
A method comprising controlling the operation of the mobile node to avoid interference with a primary user if it is determined that the mobile node that transmitted the initial message is sensing a primary user transmission. At the master node, storing a reserved preamble indicating sensing of primary user transmission;
Determining whether the preamble included in the received initial message matches the reserved preamble stored;
72. The method of claim 71, further comprising determining that the mobile node that transmitted the initial message senses a primary user transmission if the received preamble matches the reserved preamble.   73. The method of claim 71 or 72, further comprising transmitting a stored reserved preamble as part of system information to the plurality of mobile nodes. 38
In response to determining that the mobile node that transmitted the initial message senses a primary user transmission when the operation is controlled, transmission to another mobile terminal is performed in the allowed operation band. 74. A method as claimed in any one of claims 71 to 73 including controlling the master node to cease.   75. The method according to any one of claims 71 to 74, further comprising providing an uplink resource allocation message to the mobile node that transmitted the initial message. Receiving the magnitude of the identified primary user transmission signal strength from the mobile node;
75. The method of claim 74, further comprising re-determining a control action for each mobile node in response to the magnitude of the received signal strength. A method performed by a sensor node that communicates with a master node in an operating band permitted for a primary user device,
Stores reserved preamble,
Sensing the transmission of the primary user device;
Reporting the sensed primary user transmission to the master node;
The means for reporting includes reporting to the master node by storing and sending the reserved preamble in an initial message of a random access procedure.   78. The method of claim 77, wherein the sensor node further comprises receiving the reserved preamble as part of a system information broadcast by the master node.   79. The method of claim 77 or 78, further comprising receiving an uplink resource assignment from the master node. The sensor node measures the magnitude of the signal strength of the primary user transmission;
80. A method according to any one of claims 77 to 79, further comprising sending a magnitude of signal strength to the master node.   80. The claim 80 when dependent on claim 79, wherein the sensor node further comprises sending the measured signal strength to the master node using the uplink resource allocation received from the master node. Method.   The method according to any one of claims 78 to 81, wherein the sensor node further includes randomly generating a preamble used in a random access procedure. The sensor node compares the randomly generated preamble with the stored reserved preamble;
83. If the randomly generated preamble matches a stored stored reserved preamble, the sensor node serves to randomly generate another preamble for use in a random access procedure. the method of.   41. A group of instructions for causing a computer to set a programmable communication node as the master node according to any one of claims 1 to 7, 13 to 16, 22 to 27, and 35 to 40. A non-transitory computer-readable medium that stores a product of computer-executable instructions.   A computer comprising instructions for causing a computer to execute setting a programmable communication node as the sensor node according to any one of claims 8 to 12, 17 to 21, and 28 to 34 is executable. Non-transitory computer-readable medium storing a product of various instructions.

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