KR101730264B1 - Method and Apparatus for Low Power Wireless Sensor Network Communication Using Shared Channel Wake-up Transceiver in Wireless Sensor Networks - Google Patents

Abstract

Provided is a method for transmitting data in a wireless sensor network, which comprises: a step that a sensor node detects whether a wireless shared channel is occupied; a step that the sensor node transmits a wake-up signal through the wireless shared channel when the wireless shared channel is detected not to be occupied; and a step that the sensor node transmits data to the other sensor node through the wireless shared channel.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a low-power wireless sensor network communication method and apparatus using a wireless shared channel wake-up transceiver,

The present invention relates to a wireless sensor network communication method and apparatus, and more particularly, to a low power wireless sensor network communication method and apparatus using a wireless shared channel wake-up transceiver.

A wireless sensor network is a network in which many sensor nodes are installed in a desired area, and the sensed information is transmitted to a sink node through multiple hops. Once installed, it is very important to reduce power consumption because it is difficult to charge and replace batteries. The most consuming part of the sensor node is the communication part. Two approaches have been proposed to reduce power consumption in communication: a duty cycle method and a wake-up radio method.

The duty cycle method is to turn off the communication module for most of the time (sleep mode) and turn on the communication only when necessary (active mode). Through this, the sensor node exists in the sleep mode for most of the time and power consumption can be reduced because the communication module is turned off. However, in order to communicate, it is difficult for the sensor nodes to be in the active mode at the same time when they want to communicate.

The wake-up radio scheme is a method of additionally attaching a wake-up radio communication module operating at ultra low power, unlike the previous scheme using a single communication module. In this way, the main data radio remains in sleep mode and the wake-up radio communication module remains in active mode and acts as a sentry. In order to communicate, the wake-up radio sends a wake-up signal to the relative sensor node using the wake-up radio, and the wake-up radio receives the wake-up signal to change the main data radio communication module of the sensor node to the active mode, .

The wake-up radio scheme can be classified into two types according to the manner in which the wake-up radio wakes up the relative sensor node, namely, a distance-based scheme and an identity-based scheme. The distance-based method is a way in which all sensor nodes at a distance where the signal can be awakened by sending a wake-up signal. This method is advantageous in that a part for receiving a wake-up signal is simple and is effective for simultaneously sending packets to a plurality of sensor nodes. On the other hand, in unicast communication, other sensor nodes other than the communication target are woken up, . In the identity-based scheme, when a wake-up signal is sent, a sensor node is designated and a signal is sent to wake up only a desired sensor node. Although the wake-up signal is more complicated, it can operate in energy-efficient manner in unicast communication because it can wake only the desired sensor node.

In the conventional wake-up radio system, the main data radio communication module and the wake-up radio communication module use independent channels each using different radio communication channels. The independent channel scheme has the advantage that the main data radio and the wake-up radio can communicate at the same time, but uses a wider range of frequencies. On the other hand, when the wake-up radio uses an independent channel, the first sensor node wakes up the second sensor node, which is the destination of data transmission, because the channel of the wake-up radio is empty, During communication, the first and second sensor nodes may have to wait until communication between the other sensor nodes is completed.

The present invention provides a low power wireless sensor network communication method and apparatus for preventing a situation in which a main data radio is not able to communicate even though a main data radio communication module is activated due to an empty wake- .

Another aspect of the present invention is to provide a low power wireless sensor network communication method and apparatus for preventing a situation where a wake-up radio and a main data radio perform MAC duplication.

A further object of the present invention is to provide a low power wireless sensor network communication method and apparatus which can utilize frequencies more efficiently.

The problems to be solved by the present invention are not limited to the above-mentioned problems, and other matters not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of an embodiment of the present invention, a method of transmitting data in a wireless sensor network is provided. The method includes the steps of sensing whether a sensor node is occupied by a wireless shared channel, transmitting the wake-up signal over the wireless shared channel if the wireless shared channel is detected as not occupied, and And transmitting data from the sensor node to another sensor node through the wireless shared channel.

In one embodiment, the sensor node comprises a wake-up radio receiver, wherein the step of sensing whether the sensor node is occupied by a wireless shared channel in the method comprises: - detecting if the wireless shared channel is occupied using an up-radio receiver.

In one embodiment, the sensor node further comprises a wake-up radio transmitter, wherein in the method, the sensor node transmitting the wake-up signal over the wireless shared channel comprises the steps of: The sensor node may transmit the wake-up signal to a plurality of other sensor nodes within a distance range that can receive the wake-up signal via the wireless shared channel using the wake-up radio transmitter .

In one embodiment, the step of the sensor node transmitting a wake-up signal over the wireless shared channel may include determining that the sensor node has successfully transmitted the wake-up signal.

In one embodiment, the sensor node includes a main radio transmitter, wherein the step of the sensor node transmitting data to the other sensor node via the wireless shared channel comprises: Activating the main data radio transmitter and transmitting the data to the other sensor node using the main data radio transmitter if the sensor node determines that the transmission of the wake- have.

In one embodiment, the step of the sensor node transmitting data to another sensor node via the wireless shared channel may include determining that the sensor node has successfully transmitted the data.

In one embodiment, when the wireless shared channel is detected to be non-occupied, the step of the sensor node transmitting a wake-up signal over the wireless shared channel may be performed by the sensor node using the wake- And broadcasting a wake-up signal over the wireless shared channel, wherein the sensor node may share the wireless shared channel for transmission of the wake-up signal and for transmission of the data.

According to another aspect of an embodiment of the present invention, a method of transmitting data in a wireless sensor network is provided. The method comprises the steps of: sensing whether a first sensor node is occupied by a wireless shared channel; when the first sensor node is detected as not occupying the wireless shared channel, Up signal, and the first sensor node transmitting data to the second sensor node via the wireless shared channel.

In one embodiment, the first sensor node includes a wake-up radio receiver, and the step of the first sensor node detecting that the wireless shared channel is empty comprises: And detecting whether the wireless shared channel is empty by using the wireless shared channel.

In one embodiment, the first sensor node further comprises a wake-up radio transmitter, and the step of the first sensor node transmitting a wake-up signal to the second sensor node via the wireless shared channel comprises: 1 sensor node may transmit the wake-up signal to the second sensor node using the wake-up radio transmitter.

In one embodiment, the first sensor node further comprises a main data radio transmitter, wherein the step of the first sensor node transmitting data to the second sensor node via the wireless shared channel comprises: And transmitting the data to the second sensor node using the main data radio transmitter.

According to another aspect of an embodiment of the present invention, a method of receiving data in a wireless sensor network is provided. The method includes the steps of a sensor node receiving a wake-up signal from another sensor node over a wireless shared channel using a wake-up radio receiver, in response to receiving the wake-up signal, Activating the receiver and receiving data from the other sensor node via the wireless shared channel using the main data radio receiver.

According to another aspect of an embodiment of the present invention, a method of transmitting data in a wireless sensor network is provided. The method includes the steps of: a first sensor node detecting if a wireless shared channel is occupied using a wake-up radio receiver; if the wireless sensor node is detected as not occupying the wireless shared channel, Sending a wake-up signal to the second sensor node via the first sensor node, activating the main data radio transmitter by the first sensor node, and in response to activating the main data radio transmitter, And transmitting data to the second sensor node via the wireless shared channel using the main data radio transmitter.

According to another aspect of an embodiment of the present invention, a wireless sensor node device is provided. The apparatus includes a controller, a wake-up radio transceiver, and a main data radio transceiver, wherein the controller is configured to activate the main data radio transceiver in response to receiving a wake-up radio signal at the wake-up radio transceiver And the wake-up radio transceiver and the main data radio transceiver may be configured to share a wireless channel.

In one embodiment, the control unit senses that a wireless channel is occupied using the wake-up radio transceiver and, if it is detected that the wireless channel is not occupied, uses the wake-up radio transceiver to transmit the wireless channel Up signal to another sensor node through the network.

In one embodiment, the control unit may be configured to transmit data to the other sensor node via the wireless channel using the main data radio transceiver.

According to the method and apparatus according to embodiments of the present invention, the main data radio can not communicate even though the wake-up channel is empty and wake up the main data radio, It has the effect of enabling sensor network communication.

According to the method and apparatus according to embodiments of the present invention, a situation in which the wake-up radio and the main data radio do not duplicate the MAC occurs, thereby enabling low power wireless sensor network communication.

According to the method and apparatus according to embodiments of the present invention, it is possible to provide the effect that the wake-up radio and the main data radio can use the same frequency more efficiently.

1 is a conceptual block diagram of a sensor node according to an embodiment of the present invention.
2 is a flowchart illustrating a process of receiving data by a sensor node according to an embodiment of the present invention.
3 is a flowchart illustrating a process of transmitting data by a sensor node according to an embodiment of the present invention.
4 is a conceptual diagram illustrating data transmission between sensor nodes in a sensor network according to an embodiment of the present invention.
5 is a timing diagram illustrating an operation of a communication module of a sensor node in a sensor network according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of attaining them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art. To fully disclose the scope of the invention to a person skilled in the art, and the invention is only defined by the scope of the claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present invention. For example, an element expressed in singular < Desc / Clms Page number 5 > terms should be understood to include a plurality of elements unless the context clearly dictates a singular value. In addition, in the specification of the present invention, it is to be understood that terms such as "include" or "have" are intended to specify the presence of stated features, integers, steps, operations, components, The use of the term does not exclude the presence or addition of one or more other features, numbers, steps, operations, elements, parts or combinations thereof.

As used herein, the term " module " or " module " means a functional part that performs at least one function or operation, and may be implemented in hardware or software or a combination of hardware and software. In addition, a plurality of 'modules' or a plurality of 'parts' may be integrated into at least one module except for 'module' or 'module' which needs to be implemented by specific hardware, and may be implemented by at least one processor.

In addition, all terms used herein, including technical or scientific terms, unless otherwise defined, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be construed as meaning consistent with meaning in the context of the related art and may be interpreted in an ideal or overly formal sense unless explicitly defined in the specification of the present invention It does not.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, well-known functions or constructions will not be described in detail if they obscure the subject matter of the present invention.

1 is a conceptual block diagram of a sensor node according to an embodiment of the present invention. As shown, the sensor node 100 may include a wake-up radio receiver 110. During sleep mode, other components of the sensor node 100 may be powered off except for a portion of the wake-up radio receiver 110 and the power manager 170. In one embodiment, the wake-up radio receiver 110 may continuously monitor whether there is a communication request from another sensor node. In one embodiment, the wake-up radio receiver 110 may receive a wake-up signal transmitted from a wake-up radio transmitter of another sensor node.

In one embodiment, the wake-up radio receiver 110 may use a separate antenna 180 than the transceiver of the other radio. Optionally, the wake-up radio receiver 110 may share one antenna 180 with other radio blocks. Unlike the main data radio receiver 130, the wake-up radio receiver 110 may not be sensitive to the bit error rate.

The sensor node 100 may further include a wake-up radio transmitter 120. The sensor node 100 may transmit a wake-up signal via the wake-up radio transmitter 120. In one embodiment, the wake-up radio transmitter 120 may be powered on and activated to transmit a wake-up signal to the destination sensor node if there is data to transmit. In one embodiment, the wake-up signal may be a signal of a particular type including the address of the destination sensor node in an identity-based manner. Optionally, in one embodiment, the wake-up signal may be a busy-tone signal if the distance-based scheme is used.

The sensor node 100 may further include a main data radio receiver 130. The sensor node 100 may receive the data signal via the main data radio receiver 130. [ The main data radio receiver 130 is in the sleep mode and can be powered on and activated if the wake-up radio receiver 110 of the sensor node 100 has received a wake-up signal.

The sensor node 100 may further include a main data radio transmitter 140. The sensor node 100 may transmit the data signal through the main data radio transmitter 140. [ The main data radio transmitter 140 is in a sleep mode and can be powered on and activated if the wake-up radio transmitter 120 of the sensor node 100 has successfully sent a wake-up signal to the destination sensor node .

The sensor node 100 may further include a controller 150. The control unit 150 performs a function of controlling (arithmetic processing) the overall operation of the sensor node 210. In one embodiment, the controller 150 may be implemented as an integrated circuit, such as application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays micro-controllers, micro-controllers, and microprocessors.

In one embodiment, the control unit 150 may be implemented with firmware / software codes that are executable on a hardware platform that allows performing at least one function or operation. The software code may be implemented by software applications written in a suitable programming language. The software codes may be stored in the memory of the control unit 150 or stored in the memory unit 160 and then called and executed.

The sensor node 100 may further include a memory unit 160. In one embodiment, the memory unit 160 may be a flash memory type, a multimedia card micro type, a card type memory (e.g., SD or XD memory), a random access memory May be embodied as a storage medium of at least one type of memory, SRAM (Static Random Access Memory), ROM (Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), PROM .

The sensor node 100 may further include a power management unit 170. The power management unit 170 may switch to a low power consumption mode to conserve energy when there is no task to process in the process of operating the system.

The sensor node 100 may further include a sensing unit 180. The sensing unit 180 performs a function of sensing various events occurring at the arranged locations. The sensing unit 180 may include at least one sensor.

The components shown in FIG. 1 do not necessarily reflect all the functions of the sensor node 100 according to the present invention, and are not essential. Thus, it should be appreciated that the sensor node 100 in accordance with the present invention may include more or fewer components than the illustrated components.

2 is a flowchart illustrating a process of receiving data by a sensor node according to an embodiment of the present invention.

The method by which the sensor node receives data according to the present invention starts from the step S210 in which the sensor node 100 detects whether the wireless shared channel is occupied. In one embodiment, the sensor node 100 includes a wake-up radio receiver, and the sensor node 100 may be configured such that the sensor node uses the wake- Can be detected. The sensor node 100 may continuously monitor whether the wireless shared channel is occupied through the wake-up radio receiver 110. [ In step S230, the sensor node 100 may receive a wake-up signal from another sensor node on the wireless shared channel using the wake-up radio receiver 110. [

In step S250, the sensor node 100 may activate the main data radio receiver 130 in response to receiving the wake-up signal and in step S270 the sensor node 100 may activate the main data radio receiver 130 may be used to receive data from other sensor nodes over a wireless shared channel.

3 is a flowchart illustrating a process of transmitting data by a sensor node according to an embodiment of the present invention.

The method of transmitting data by the sensor node according to the present invention starts from step S310 in which the sensor node 100 detects whether the wireless shared channel is occupied. In one embodiment, the sensor node 100 includes a wake-up radio receiver, and the sensor node 100 can sense whether the wireless shared channel is occupied by the sensor node using a wake-up radio receiver.

In step S330, if it is detected that the wireless shared channel is not occupied, the sensor node may transmit the wake-up signal through the wireless shared channel. In one embodiment, the sensor node 100 further comprises a wake-up radio transmitter 120, wherein the sensor node 100 transmits the wake-up signal over the wireless shared channel, The sensor node 100 may use the wake-up radio transmitter 120 to transmit a wake-up signal to a plurality of other sensor nodes within a distance range that can receive the wake-up signal over the wireless shared channel . Here, the wake-up signal may be a busy-tone signal if the distance-based method is used.

Optionally, the sensor node 100 transmits a wake-up signal over a wireless shared channel so that the sensor node 100 uses the wake-up radio transmitter 120 to transmit a wake- Up signal to a particular sensor node that is within a distance range that can receive the wake-up signal. Here, the wake-up signal may be a signal having a specific type including the address of the destination sensor node.

In one embodiment, the sensor node 100 transmitting a wake-up signal over a wireless shared channel may comprise determining whether the sensor node 100 has successfully transmitted the wake-up signal.

In step S350, the sensor node 100 may transmit data to another sensor node through a wireless shared channel. In one embodiment, the sensor node 100 includes a main radio transmitter 140 and the sensor node 100 transmits data to another sensor node via a wireless shared channel, 100 may activate the main data radio transmitter 140 and may transmit data to another sensor node using the main data radio transmitter 140 in step S370.

In step S390, the sensor node 100 determines whether the data transmission is successful, and terminates the data communication if the data transmission is successful. When terminating the data communication, the sensor node 100 may switch the transceivers 130 and 140 of the main data radio to the sleep mode. In one embodiment, when terminating the data communication, the sensor node 100 may switch the wake-up radio transmitter 120 to the sleep mode.

4 is a conceptual diagram illustrating data transmission between sensor nodes in a sensor network according to an embodiment of the present invention.

As shown in FIG. 4, it is assumed that the sensor node B and the sensor node C are in communication, and the sensor node A has data to be transmitted to the sensor node D. First, the sensor node A uses its own wake-up radio receiver to detect whether the wireless shared channel is occupied. Since the sensor node B and the sensor node C transmit and receive data through the wireless shared channel, the wake-up radio receiver of the sensor node A determines that the sensor node B and the sensor node C are in communication, that is, It can be confirmed that it is in the middle. Accordingly, the sensor node A continuously monitors the wireless shared channel without sending a wake-up signal to the sensor node D, and waits for the existing communication (that is, communication between the sensor node B and the sensor node C) to be terminated.

When the communication between the sensor node B and the sensor node C is terminated and it is detected that the wireless shared channel is empty for a predetermined time, the sensor node A uses the wake-up radio transmitter of the sensor node A to transmit a wake- D. Thereafter, if the wake-up signal is successfully transmitted, the sensor node A activates its main data radio transmitter and the sensor node D activates its main data radio receiver to initiate data communication between the sensor node A and the sensor node D .

Accordingly, the present invention can reduce energy waste by not activating the main data radio transceiver of the sensor node A and the sensor node D during a time when communication is impossible. Also, according to the conventional method, it is necessary to check whether each radio channel is occupied before each of the wake-up radio and the main data radio communicate. In the present invention, however, only the wake- If the wireless channel is not occupied, a wake-up signal is sent and the main data radio starts data communication as soon as it wakes up without detecting the wireless channel, thereby omitting duplicated channel detection process and improving energy efficiency .

5 is a timing diagram illustrating an operation of a communication module of a sensor node in a sensor network according to an embodiment of the present invention.

5 is a timing diagram in which the same communication scenario as FIG. 4 is concentrated on a radio communication module. When the sensor node C has data to be sent to the sensor node B, the wake-up radio receiver of the sensor node C first detects the wireless shared channel and checks whether the wireless shared channel is occupied. If the wireless shared channel is not occupied Up signal is sent via the wake-up radio transmitter of sensor node C to wake sensor node B. Then, the main data radio transceiver of sensor node B and sensor node C is activated to start data communication.

Suppose that data to be sent from sensor node A to sensor node D is generated while sensor node B and sensor node C are communicating. The sensor node A senses a wireless shared channel for data communication. At this time, since the data communication between the sensor node B and the sensor node C has not yet ended, the sensor node A can know that the wireless shared channel is occupied. Therefore, the sensor node A waits for the wireless channel to be detected until the communication between the other sensor nodes is completed using the wake-up radio receiver without turning on the main data radio transmitter. As described above, since the radio channel is occupied by the communication between the sensor node B and the sensor node C, the sensor node A waits without waking up the main data radio transceiver, thereby reducing energy waste. The sensor node A continuously senses the wireless channel using the wake-up radio receiver. When the sensor node B and the sensor node C communicate with each other and sense that the channel is empty, the sensor node A sends a wake- To prepare data communication. After that, the sensor node A and the sensor node D start data communication through the main data radio, and when the communication is finished, all the sensor nodes detect the wireless channel by the wake-up radio and prepare for the next communication.

In the embodiments disclosed herein, the arrangement of the components shown may vary depending on the environment or requirements in which the invention is implemented. For example, some components may be omitted or some components may be integrated into one. In addition, the arrangement order and connection of some components may be changed.

Although the present invention and its various functional elements have been described in terms of specific embodiments, it is to be understood that the invention may be implemented in hardware, software, firmware, middleware, or a combination thereof and may be implemented as a system, subsystem, It should be understood that the invention may be utilized in various other embodiments. When implemented in software, the elements of the present invention may be instructions / code segments for performing necessary tasks. The program or code segments may be stored in a machine-readable medium, such as a processor-readable medium, or a computer program product. A machine-readable medium or a processor-readable medium may include any medium that can be read by a machine (e.g., processor, computer, etc.) and capable of storing or transmitting information in an executable form.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. Accordingly, the technical scope of the present invention should be determined only by the appended claims.

100: sensor node
110: wake-up radio receiver
120: Wake-up radio transmitter
130: main data radio receiver
140: main data radio transmitter
150:
160:
170:
180: sensing unit

Claims (17)

A method of transmitting data in a wireless sensor network,
Sensing a wireless shared channel occupancy by a sensor node using a wake-up radio receiver,
Up radio transmitter to activate the wake-up radio transmitter when the wake-up radio transmitter is not occupied, activating the wake-up radio transmitter to activate the wake-up radio transmitter, The sensor node transmitting a wake-up signal over the wireless shared channel, and
Activating the main data radio transmitter by applying power to a main radio transmitter and transmitting the data to the other sensor node via the wireless shared channel using the activated main data radio transmitter , ≪ / RTI >
Wherein the sensor node shares the wireless shared channel for transmission of the wake-up signal and for transmission of the data. delete The method according to claim 1,
Wherein the step of the sensor node transmitting a wake-up signal over the wireless shared channel comprises the step of the sensor node transmitting the wake-up signal over the wireless shared channel using the wake- And transmitting the wake-up signal to a plurality of other sensor nodes having the wake-up signal. The method of claim 3,
Wherein the step of the sensor node transmitting a wake-up signal over the wireless shared channel comprises determining that the sensor node has successfully transmitted the wake-up signal. 5. The method of claim 4,
The sensor node transmits data to another sensor node via the wireless shared channel when the sensor node determines that the transmission of the wake-up signal is successful, And transmitting the data to a node. 6. The method of claim 5,
Wherein the step of the sensor node transmitting data to the other sensor node via the wireless shared channel includes determining whether the sensor node has successfully transmitted the data. The method according to claim 1,
If it is detected that the wireless shared channel is not occupied, the step of the sensor node transmitting a wake-up signal over the wireless shared channel
Wherein the sensor node broadcasts a wake-up signal over the wireless shared channel using the wake-up radio transmitter. delete delete delete delete A method for receiving data in a wireless sensor network,
The sensor node receiving a wake-up signal from another sensor node via a wireless shared channel using a wake-up radio receiver,
In response to receiving the wake-up signal, activating the main data radio receiver by applying power to the main data radio receiver;
Receiving data from the other sensor node over the wireless shared channel using the main data radio receiver,
Wherein the sensor node shares the wireless shared channel for receiving the wake-up signal and for receiving the data. delete 15. A computer-readable recording medium having recorded thereon a program, the program comprising instructions that when executed by a computer perform the method of any one of claims 1, 3, 7, and 12 The computer-readable recording medium. As a wireless sensor node,
The control unit,
Wake-up radio transmitter and receiver, and
Main Data Radio Transmitter and Receiver
Lt; / RTI >
Wherein the controller is configured to power the main data radio receiver in response to receiving a wake-up radio signal at the wake-up radio receiver to activate the main data radio receiver,
Up radio receiver to detect whether the wireless shared channel is occupied and to activate the wake-up radio transmitter by powering the wake-up radio transmitter if it is detected that the wireless shared channel is not occupied Respectively,
Up signal to the other sensor node via the wireless shared channel using the activated wake-up radio transmitter,
Wherein the wake-up radio transmitter and receiver and the main data radio transmitter and receiver are configured to share the wireless shared channel. delete 16. The method of claim 15,
Wherein the controller is configured to transmit data to the other sensor node via the wireless shared channel using the main data radio transmitter.

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