KR20110130276A - A beacon-enable mode hybirid superframe structure of contention-based wireless body area network mac protocol and network communication method thereof - Google Patents

Abstract

PURPOSE: An MAC protocol in a WBAN(Wireless Body Area Network) and a wireless network communication method using the same are provided to guarantee data transmission in a medical device or consumer electronics of a user by providing an inactive period as an opportunity period through an OCDP(Opportunistic Contention Decision Period) between an active period and an inactive period. CONSTITUTION: An OCDP is located between an active period and an inactive period to additionally transmit data and includes an RO(Request of Opportunity) sub period and an AO(Acknowledgement of Opportunity) sub period. The RO sub period is a period for an opportunity period use request according to the property of each device. The AO sub period is a period for receiving response by a coordinator.

Description

MAC protocol in a wireless body communication network and a wireless network communication method using the same

The present invention relates to a MAC protocol in a wireless body communication network and a wireless network communication method using the same. More particularly, an OCDP is placed between an active period and an inactive period of a superframe. Beacons in a hybrid superframe structure in beacon-enable mode that can provide flexible data transmission not only to medical devices but also to consumer electronics by providing periods as opportunity competition periods when needed The present invention relates to a physical communication network MAC protocol based on an opportunity mode contention competition based on an available mode, and a wireless network communication method using the same.

The present invention relates to a MAC protocol in a wireless body communication network and a wireless network communication method using the same.

Recently, the wireless body area network (WBAN) has attracted attention as a wireless technology for medical / non-medical communication in the human area following WLAN and WPAN technologies.

WBAN is a network capable of wireless communication in the human body area. Here, the human body wireless communication refers to wireless communication in which terminals located inside or outside the human body can communicate with other devices in a range of about 3M.

One of the big features that distinguishes WBAN from other networks, such as WLAN and WPAN, is that medical devices are considered as a killer item. Another big feature is that it is considering wireless communication of implantable wireless devices that are implanted inside the human body.

Accordingly, WBAN is currently applied for various purposes, and can be classified into medical and non-medical wireless devices. In other words, non-medical field for communication between consumer electronics and human body implanted wireless device that is implanted inside the human body and copes with any abnormality in the human body and monitors the health condition inside the human body and 3 meters outside the human body. It can be divided into external devices to transmit and receive from the medical sensor (sensor) within.

This WBAN uses a super frame structure to coordinate medium access of each device. One super frame is divided into an active period in which the device can send and receive data and an inactive period in which the device can operate in a sleep mode.

The active period is divided into a contention access period (CAP) section in which medium access is possible through competition between devices, and a connection free period (CEP) section in which only a designated device can exchange data at a designated time.

The CFP section is divided into a predetermined number of GTSs (Guranteed time slots) and used. In the GTS section, resources are reserved only for a predetermined device, and data cannot be sent except for the corresponding device. In WBAN, this reservation technique can be applied for sending important data without collision, for urgent data and real-time data transmission.

However, according to a conventional protocol designed to allow all devices to sleep in an inactive period to provide low power of the medical device and the coordinator, emergency data of the medical device and data requiring QoS support are required. Because of the delay in transmission, there is a problem that it is difficult to impart urgency to data transmission requiring QoS.

In addition, there is a problem that the transmission of data that occurs continuously and in large quantities such as file transmission and video audio streaming transmission of a consumer electronic device may be delayed.

The present invention has been invented to solve the above problems, the present invention is to provide an OCDP between the active period (inactive period) and the inactive period (inactive period) of the superframe to provide an inactive period (inactive period) to medical devices and home appliances The purpose of the present invention is to provide a MAC protocol in a wireless body communication network and a wireless network communication method using the same, which can guarantee flexible data transmission to not only a medical device but also a consumer electronic device by providing an opportunity competition section when necessary. It is done.

The present invention also provides an OCDP between an active period and an inactive period of a superframe, so that devices requesting additional transmission send an OCM request message during a time slot corresponding to each group. Inactive periods can be used as opportunity competition periods when needed, thereby increasing transmission throughput of emergency data from medical devices, data requiring QoS support, and large amounts of data generated by consumer electronics (Comsumer Electronics). An object of the present invention is to provide a MAC protocol in a body communication network and a wireless network communication method using the same.

In order to achieve the above object, the MAC protocol and the wireless network communication method using the same in the wireless physical communication network according to the present invention, in the WBAN MAC protocol using the MAC of the superframe structure, the active period (active period) and inactive There is an OCDP period (opportunistic contention decision period) that allows additional transmission of data between periods (inactive period).

In this case, the OCDP interval, RO sub period for each device to request the use of the opportunity competition period (Opportunity period) according to the characteristics of the device; And an AO sub-interval for receiving a response by the coordinator.

The RO sub-interval may include: a RO 1 section for enabling a medical device to transmit an OCP frame; A RO 2 section that allows a low speed consumer electronic device to transmit an occupancy contention message (OCM) frame; And a three RO section for allowing a high-speed consumer electronic device (Comsumer Electronics) to transmit an OCC frame.

On the other hand, if any one of the devices that have transmitted the OCM (opportunity contention message) frame is assigned a channel, the rest of the devices except the channel assigned device to enter a sleep mode (sleep mode) to reduce power consumption It is preferable to process.

The coordinator selects any one of four preset modes based on the information transmitted through the RO 1 section, the RO 2 section, and the RO 3 section, and requests the use of an opportunity competition period. ACK is transmitted through the AO sub-interval.

Meanwhile, when a medical device requests the use of an opportunity competition period, the slotted-CSMA / CA algorithm is used periodically in all the operation periods in order to minimize power consumption of the medical devices.

In addition, when slow consumer or medical devices and consumer electronics request the use of an opportunity competition period, they are slotted in every opportunity competition period to guarantee additional transmission. Allow the CSMA / CA algorithm to be used.

When the consumer electronics requests the use of the opportunity competition period, the CSMA / CA (DCF) algorithm is used in all the opportunity competition periods to guarantee the high speed transmission.

On the other hand, if the high-speed home appliances and medical devices or low-speed CE home appliances request the use of the opportunity competition period (Opportunity period), the CSMA / CA (DCF) algorithm is to be used for all the opportunity competition period, but other characteristics It is desirable to allow the slotted-CSMA / CA algorithm to be used periodically to ensure additional transmissions of devices with a network.

According to the present invention, the present invention places an OCDP between an active period and an inactive period of a superframe to provide an inactive period to the medical device and the home appliance as an opportunity competition period when necessary. As a result, a flexible data transmission can be guaranteed not only for the medical device but also for the consumer electronics device.

The present invention also provides an OCDP between an active period and an inactive period of a superframe, so that devices requesting additional transmission send an OCM request message during a time slot corresponding to each group. Inactive period can be used as an opportunity competition period when necessary, thereby increasing the throughput of the transmission of a large amount of data generated from emergency data of the medical device, data requiring QoS support, user electronics (Comsumer Electronics), There is an advantage to lower the transmission delay rate.

1 illustrates a MAC protocol in a wireless body communication network according to a preferred embodiment of the present invention.
2 is a diagram illustrating a detailed configuration of an opportunity competition section illustrated in FIG. 1;
3 illustrates four modes of the present invention.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment of the MAC protocol and a wireless network communication method using the same in a wireless body communication network according to the present invention as described above will be described in detail.

The present invention maintains an inactive period for a medical device which is always configured in a network at any time, but a certain situation (for example, a medical device wants to transmit emergency data, requires QoS support). When there is a situation in which you want to transmit data, a file transfer from a consumer electronics device, a situation in which you want to transmit continuous and massive data such as video audio streaming transmission, etc., the channel is temporarily blocked by a demand-driven technique. We propose a MAC protocol in a wireless body communication network that activates and acquires a channel by a competition technique.

FIG. 1 is a diagram illustrating a MAC protocol in a wireless body communication network according to a preferred embodiment of the present invention, and FIG. 2 is a diagram showing a detailed configuration of an opportunity competition section shown in FIG. 1.

As shown in FIG. 1 and FIG. 2, the present invention enables additional transmission of data between an active period and an inactive period in the WBAN MAC protocol using a superframe MAC. An opportunistic contention decision period is allowed. In other words, the Opportunity Period is further added to the conventional MAC protocol of IEEE 802.15.4.

Table 1 shows a table adding frame values used to use an opportunity competition period.

In order to request the use of the opportunity competition period through the OCDP interval, the OCDP provides two control frames. The first is an OCM frame (opportunity contention message frame), which is a control frame for making a request to use an opportunity competition period, and the second is an OCM ACK frame, which is a response control frame by a coordinator. At this time, the WBAN-based devices may transmit the OCM frame to the coordinator to request the use of the opportunity contention interval.

[Table 2] shows a table for explaining the use request and the bit value of the ACK of the Opportunity period used in the OCDP interval.

That is, the OCDP interval provides a demand-driven scheme, and each device receives an RO sub-interval and an AO (acknowledgement) to receive a response by the coordinator according to the characteristics of the device. of opportunity).

At this time, the RO (request of opportunity) sub-section is composed of three sub-intervals in order to request the use of the opportunity competition period according to the characteristics of the device requiring the use of the opportunity competition period (Opportunity period).

More specifically, the request of opportunity (RO) subdivision includes the RO 1 section, which enables medical devices to transmit OCC frames, and low speed consumer electronics (OPCM) opportunity contention messages (OCMs). RO 2 section which enables frame transmission and RO 3 section which enables high-speed consumer electronics (Comsumer Electronics) to transmit an Oportion Contention Message (OCM) frame.

In summary, in the RO subsection consisting of the RO section 1 and the RO section 3, the section in which the OCM frame can be transmitted is determined according to the characteristics of the WBAN device.

That is, the RO section 1 is a sub section provided to enable a medical device to transmit an OCP frame, and the RO section 2 is an OCM generated by a consumer electronic device that generates continuous data or a large amount of data. (opportunity contention message) A subsection provided to enable transmission of a frame. The RO 1 section and the RO 2 section may similarly request the use of the opportunity competition period through the OCM frame in each section.

Meanwhile, the RO section 3 is a sub section provided to enable an apparatus requesting an ad hoc mode to transmit an Oportion Contention Message (OCM) frame. This section provides a way to use a module of the DCF (optional) to support communication between devices in the ad-hoc mode of the existing IEEE 802.11.

Table 3 shows a table that describes the devices that can request the use of an opportunity competition period in each subsection of the OCDP interval.

Meanwhile, the OCDP interval uses a delegate request method. Therefore, if two or more medical devices attempt to send an OCM frame through competition in the RO 1 period, if one device that acquires the channel transmits the OCM frame, then the remaining devices that have completed the backoff are then referred to themselves through the CCA. Instead, it determines that the OCM frame transmission has already been made, and then enters the sleep mode and receives the OCM ACK frame together when the AO subsection starts, so that the information on the opportunity competition period can be known.

The reason for this surrogate request is that the coordinator can select one of four preset modes (Mode A, Mode B, Mode C, and Mode D) in combination according to the OCM frame received through the RO subsection. .

Table 4 shows a table describing four modes resulting from the combination of the RO 1 section, the RO 2 section, and the RO 3 section.

In summary, the coordinator supports the use of Mode A to Mode D based on the characteristics of each device through a message requested in the OCM frame in the RO subsection of the OCDP interval.

Hereinafter, four modes will be described in detail with reference to the accompanying drawings.

3 is a diagram illustrating the four modes of the present invention.

Referring to FIG. 3, Mode A is used when a medical device that is generated at a small size at a low speed through the RO 1 period generates an OCM frame and requests the coordinator to use an opportunity competition period. That is, when a medical device requests the use of an opportunity competition period. In this case, in order to minimize power consumption of medical devices, a periodic slotted-CSMA / CA algorithm is used in every operation period.

In general, the sensing data that is completed and not completed in the active period is discarded after a certain time or exceeds the maximum number of backoffs. In Mode A, an opportunity competition period is used. Mode A does not activate all of Inactive's total time, provides wake up and sleep modes to acquire channels, and keeps the coordinator unnecessarily awake for the entire superframe.

Mode B is used when a continuous large amount of data from a home appliance occurs. That is, Mode B is used when a low speed consumer device or a medical device and a low cost consumer device request the use of an opportunity competition period. In this case, the slotted-CSMA / CA algorithm is used in all opportunity competition periods to ensure additional transmission.

In other words, the data transmission is provided so that the transmission delay due to the inactive period does not increase. When the OCM frame is generated and requested in the RO 2 period, the Opportunity period is activated to the end of the current superframe as in Mode B. If the data generated with this characteristic is not transmitted quickly, the CAP section may be raced together with the medical device in the active period of the next superframe. It is desirable to provide a period.

Mode C is used when a device requiring only ad hoc mode requests the use of an opportunity competition period through the RO 3 subsection. That is, Mode C is used when a high speed home appliance (Comsumer Electronics) requests the use of an opportunity competition period. In this case, it is preferable to use the CSMA / CA (DCF) algorithm in all opportunity competition periods to ensure high-speed transmission.

The DCF mode is optionally mounted according to the development purpose and characteristics of the device, and transmits the possession of the module to the coordinator when incorporated into the network. The RO 3 section is created when there are two or more such devices, so that Mode C and Mode D are also available.

Mode D is used when both a slotted CSMA-CA and a DCF type CSMA-CA device transmit an OCM frame. That is, Mode D is used when the high speed appliance and the medical device or the low speed CE appliance request the use of an opportunity competition period. In this case, the CSMA / CA (DCF) algorithm should be used in every opportunity competition period, but the time slotted-CSMA / CA algorithm uses periodically to guarantee additional transmission of devices having different characteristics. desirable. In other words, each CSMA-CA competition scheme is used to cross each other in slot units.

The present invention defines a method of short-range communication encompassing medical devices and user electronic devices. According to the present invention as described above, the present invention has the advantage of enabling non-medical services (video, mp3, portal services, etc.) while enabling remote diagnosis / prescription in real time through a low delay and flexible transmission method. have.

In addition, the present invention has the advantage that can provide a service that can provide a number of services at the same time to reduce the production cost of the enterprise and the user convenience.

In addition, the present invention has the advantage of enabling efficient remote diagnosis / prescription for residents, the elderly, disabled people in the area not receiving medical services.

The present invention has been shown and described with respect to specific preferred embodiments thereof. However, the present invention is not limited to the above-described embodiments, and various changes and modifications may be made without departing from the technical spirit of the present invention by those skilled in the art. Accordingly, the scope of the present invention should be construed as being determined not by the specific embodiments but by the appended claims.

Claims (9)

In the WBAN MAC protocol using the MAC of the superframe structure,
Mac protocol in a wireless body communication network and a wireless communication using the same, characterized in that there is an opportunistic contention decision period (OCDP) that allows additional transmission of data between the active period and the inactive period (active period) Network communication method.
The method of claim 1, wherein the OCDP interval,
An RO sub-section for each device to make a request for using an opportunity competition period according to the characteristics of the device; And
AO sub-interval for receiving a response by the coordinator; Mac protocol in a wireless body communication network comprising a and wireless network communication method using the same.
The method of claim 2, wherein the RO sub-section,
An RO 1 section that enables the medical device to transmit an occupancy contention message (OCM) frame;
A RO 2 section that allows a low speed consumer electronic device to transmit an occupancy contention message (OCM) frame; And
Mac protocol in a wireless body communication network and a wireless network communication method using the same; comprising a; RO section for enabling a high-speed consumer electronics (Comsumer Electronics) frame to transmit an OCP (opportunity contention message) frame.
The method of claim 3,
When any one of the devices that transmit the OCM frame is allocated with a channel, the remaining devices except for the channel-allocated device enter a sleep mode to reduce power consumption. Mac protocol in a wireless body communication network and a wireless network communication method using the same.
The method of claim 4, wherein
The coordinator selects one of four preset modes based on the information transmitted through the RO 1 section, the RO 2 section, and the RO 3 section, and requests the use of an opportunity competition period. And a MAC protocol in a wireless body communication network for transmitting an ACK to the device through the AO sub-interval.
The method of claim 5,
When a medical device requests the use of an opportunity competition period, the periodic slotted-CSMA / CA algorithm is used in every opportunity competition period in order to minimize the power consumption of the medical devices. MAC protocol in a wireless body communication network and a wireless network communication method using the same.
The method of claim 5,
If low speed consumer electronics or medical devices and low cost consumer electronics request the use of an opportunity competition period, slotted-CSMA at every opportunity competition period to ensure additional transmission. Mac protocol in a wireless body communication network and a method for wireless network communication using the same, characterized in that the / CA algorithm is used.
The method of claim 5,
When a consumer electronics device requests the use of an opportunity competition period, the CSMA / CA (DCF) algorithm is used for all opportunity competition periods to ensure high-speed transmission. MAC protocol in a wireless body communication network and a wireless network communication method using the same.
The method of claim 5,
When a high speed appliance and a medical device or a low speed CE appliance request the use of the opportunity competition period, the CSMA / CA (DCF) algorithm is used in all the opportunity competition periods, but has different characteristics. Mac protocol in a wireless body communication network and a method for wireless network communication using the same, characterized in that the slotted-CSMA / CA algorithm is used periodically to ensure the additional transmission of the devices.

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