KR20190014944A - Terminal device, and packet transmitting method thereof - Google Patents

Abstract

Disclosed in the present invention is a technology for realizing a new method of determining a transmission time point for the transmission of a next uplink packet differently every time so as to perform the uplink packet transmission irregularly, thereby reducing a possibility of packet collision by avoiding a continuous/repeated packet collision situation that may occur between IoT terminals, and further improving a quality of an Internet of things (IoT) service. A terminal device comprises: a packet transmitting unit for transmitting an uplink packet when a transmission time arrives; a packet receiving unit for performing monitoring for downlink packet reception in a downlink time interval predefined after transmitting the uplink packet; and a transmission time point determining unit for determining, when the downlink packet reception is successful, a transmission time point for transmission of a next uplink packet based on a downlink time interval in which the downlink packet reception was successful.

Description

TECHNICAL FIELD [0001] The present invention relates to a terminal apparatus and a method of transmitting an uplink packet of the apparatus,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to Internet (IoT) technology, and more particularly, to a technology capable of improving the quality of Internet service (IoT) by reducing the possibility of packet collision between Internet terminals.

Internet of Things (IoT) technology, which connects information of living things through wired / wireless networks in various fields such as healthcare, remote meter reading, smart home, smart car and smart farm, is attracting attention.

The following is a brief description of the IoT network structure for providing the Internet (IoT) service based on the Internet (IoT) technology.

The IoT network includes a object Internet terminal (IoT terminal) for continuously transmitting data, a customer terminal having an object Internet application (hereinafter referred to as " IoT application ") for checking data of the remote IoT terminal and controlling the IoT terminal, (Eg, IoT appserver) that connects the IoT terminal and the client terminal (IoT app) through a wired / wireless network, a gateway (eg, IoT base station) that performs packet transmission and reception between the object internet terminal and the network device do.

The quality of the Internet (IoT) service provided in the IoT network structure is greatly influenced by the success rate of the uplink packet / downlink packet reception / reception between the three nodes of the IoT terminal / IoT base station / network device.

The IoT terminal operates with a relatively simple uplink packet transmission scheme in which data (uplink packet) is transmitted (transmitted) every predetermined uplink transmission period.

On the other hand, the IoT terminal is divided into several types according to a downlink packet reception method. In order to support low power of this type, a response to data (uplink packet) after data transmission (uplink packet transmission) (Hereinafter, referred to as a reception restriction type) capable of receiving only the downlink time period of a predetermined time unit limited to a specific number of times.

For example, assuming that a certain period of time is 1 second, a specific number of times is 2, and a time interval between time intervals is 1 second, the IoT terminal operating as a reception restriction type transmits data ( Downlink packet is transmitted (transmitted), downlink packet reception is possible in the first downlink time interval (DL1) after 1 second based on the completion of transmission of the uplink packet, and DL1 is terminated when no downlink is received It is possible to receive the downlink packet in the second downlink time interval (DL2) after 3 seconds based on the time point of 1 second after the completion of the uplink packet transmission.

On the other hand, in the case of the IoT base station, according to the technical standard, it is possible to simultaneously receive uplink packets from various IoT terminals through different channels, while in the case of downlink packets, only one channel can be transmitted at a time, There are many constraints such that another channel can not be used for uplink packet reception during link packet transmission.

Thus, in the IoT network structure, due to the fact that each IoT terminal uniformly repeats the uplink packet transmission every fixed uplink transmission period and many constraints related to the downlink transmission of the IoT base station, the IoT There may occur a situation in which DL1 and DL2 capable of receiving an uplink packet or a downlink packet receivable continuously overlap between the terminals and the packet repeatedly collides with each other.

However, in the current Internet (IoT) technology, it is possible to solve this situation even if there occurs a situation in which DLo, DL2 capable of receiving uplink packets or downlink packets continuously overlap between IoT terminals as described above, There is no room available and there is no way to avoid this situation.

Accordingly, in the present invention, it is assumed that each IoT terminal uniformly repeats the uplink packet transmission every fixed uplink transmission period, and the IoT base station, which can be caused by a number of constraints related to downlink transmission of the IoT base station, We propose a new scheme that avoids persistent / repetitive packet collision situations.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the quality of the Internet service (IoT) by reducing the possibility of packet collision between Internet terminals (IoT terminals) There is.

According to a first aspect of the present invention, there is provided a terminal apparatus comprising: a packet transmission unit for transmitting an uplink packet when a transmission time arrives; A packet receiver for performing monitoring for downlink packet reception in a downlink time interval defined before transmission of the uplink packet; And a transmission time determining unit for determining a transmission time point for the next uplink packet transmission based on a downlink time interval in which the downlink packet reception is successful, when the downlink packet reception is successful.

Preferably, after transmitting the uplink packet, the terminal apparatus may be capable of receiving the downlink packet for the uplink packet only in a downlink time interval of a predetermined fixed time unit.

Preferably, the transmission time determining unit determines a time point between a start point of a downlink time interval in which the downlink packet was successfully received, an uplink time interval used for uplink packet transmission, an uplink time interval and a first downlink time interval Interval, and a predefined uplink transmission period, as the transmission time point for the next uplink packet transmission.

Preferably, the transmission time determination unit may determine the uplink time interval and the specific time point prior to the time interval from a point in time when the uplink transmission period elapses from the start time of the downlink time interval in which the downlink packet reception was successful , It can be determined as a transmission time point for transmission of the next uplink packet.

Preferably, the transmission time point for transmission of the next uplink packet may be different according to a downlink time interval in which the reception of the downlink packet is successful, which of the specific times is a downlink time interval.

According to a second aspect of the present invention, there is provided an uplink packet transmission method for a terminal device, the uplink packet transmission method including: a packet transmission step of transmitting an uplink packet when a transmission time arrives; Performing a monitoring for downlink packet reception in a downlink time interval defined before transmission of the uplink packet; And determining a transmission time point for the next uplink packet transmission based on a downlink time interval in which the downlink packet reception is successful, when the downlink packet reception is successful.

Preferably, after transmitting the uplink packet, the terminal apparatus may be capable of receiving the downlink packet for the uplink packet only in a downlink time interval of a predetermined fixed time unit.

Preferably, the transmission time determination step further includes a step of determining a transmission time point of the uplink time interval, the uplink time interval, and the first downlink time interval used for transmission of the uplink packet, A time interval, and a predefined uplink transmission period, as a transmission point for transmission of the next uplink packet.

Preferably, the transmission time determination step may include determining the transmission time point based on the uplink time interval and the specific time point prior to the time interval from a time point that has elapsed by the uplink transmission period at the start time of the downlink time interval, As the transmission time point for the next uplink packet transmission.

Thus, according to the terminal device of the present invention and the uplink packet transmission method of the device, it is possible to avoid the continuous / repeated packet collision situation that may occur between the Internet terminals (IoT terminals) It is possible to obtain an effect of improving the quality of the IoT service.

FIG. 1 is an exemplary diagram illustrating a structure of an Internet (IoT) network to which the present invention is applied.
FIG. 2 is an exemplary diagram showing a case where a continuous / repeated packet collision situation occurs according to the existing technology.
3 is a block diagram illustrating a configuration of a terminal device according to a preferred embodiment of the present invention.
FIG. 4 is an exemplary diagram showing a case where a continuous / repeated packet collision situation is avoided and the possibility of packet collision is lowered according to the technique proposed by the present invention.
5 is a flowchart illustrating an uplink packet transmission method of a terminal according to a preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a network structure of Internet of Things (IOT) to which the present invention is applied.

1, the Internet IoT network structure to which the present invention is applied includes an Internet Internet terminal (IoT terminal, for example, terminals A, B, and C) that continuously transmits data, A customer terminal (not shown) provided with an IoT app for checking data of the object Internet terminal and controlling the object internet terminal, a network device for connecting the object internet terminal and the customer terminal (IoT app) through a wired / wireless network And an IoT base station 200 serving as a gateway for transmitting and receiving a packet between the object Internet terminal and the network device.

In the Internet (IoT) technology, the IoT terminal transmits (transmits) data (uplink packet) through a randomly selected channel among a plurality of channels used for transmitting and receiving a packet every predefined uplink transmission period. And operates in a relatively simple uplink packet transmission scheme.

On the other hand, the IoT terminal is divided into several types according to a downlink packet reception method. In order to support low power of this type, a response to data (uplink packet) after data transmission (uplink packet transmission) (Hereinafter, referred to as a reception restriction type) capable of receiving only the downlink time period of a predetermined time unit limited to a specific number of times.

For example, assuming that a certain period of time is 1 second, a specific number of times is 2, and a time interval between time intervals is 1 second, the IoT terminal operating as a reception restriction type transmits data ( Downlink packet is transmitted (transmitted), downlink packet reception is possible in the first downlink time interval (DL1) after 1 second based on the completion of transmission of the uplink packet, and DL1 is terminated when no downlink is received It is possible to receive the downlink packet in the second downlink time interval (DL2) after 3 seconds based on the time point of 1 second after the completion of the uplink packet transmission.

When the downlink packet is successfully received in DL1 or DL2 after transmitting the uplink packet, the IoT terminal waits in the sleep state until the next uplink transmission cycle arrives and the next data (uplink packet) is transmitted (transmitted) , If the downlink packet reception fails in both DL1 and DL2, an uplink packet (data) retransmission process is performed according to a predetermined rule before the current uplink transmission period elapses.

The above-mentioned reception restriction type is an IoT terminal used in IoT technology (LoRa: Long Range) specialized in small amount data transmission supporting low-rate transmission (<1 kbps) and low power This mainly adopts / operates.

Meanwhile, in the case of the IoT base station, according to the technical standard, it is possible to simultaneously receive uplink packets from various IoT terminals through different channels.

On the other hand, in the case of the IoT base station, according to the technical standard, in the case of the downlink packet, only one channel can be transmitted at a time, and another channel can not be used for receiving the uplink packet during transmission of the downlink packet through one channel There are many constraints.

In the IoT network structure, when several IoT terminals of the reception restriction type coexist, each IoT terminal uniformly repeats uplink packet transmission every fixed uplink transmission period, Due to a number of related constraints, a situation may occur in which the packet may repeatedly collide with DLo or DL2, which may receive downlink packet transmission time or downlink packet transmission time between IoT terminals.

Referring to FIG. 2, a continuous / repeated packet collision situation will be briefly described below. For convenience of explanation, the terminals A, B, and C of the reception restriction type will be described as the IoT terminal.

2, each of the terminals A, B, and C uses a plurality of channels (# 0, # 1, # 2, ..., # 2, # 3,...).

2, the terminal A first transmits the uplink packet A UL through the channel # 0 and the next terminal C transmits the uplink packet A through the channel # 3, C UL), and the next terminal B is transmitting the uplink packet (B UL) through the channel # 1.

First, referring to the terminal A, the base station 200 receives the uplink packet (A UL) from the terminal A through the channel # 0 and transmits the uplink packet (A UL) The downlink packet A DL1 to the terminal A will be attempted to be transmitted through the same channel # 0 on which the uplink packet A UL is received in the downlink time period DL1 after the transmission of the downlink packet DL Because there is no packet / uplink packet, the downlink packet A DL1 will normally be transmitted and successfully received at terminal A.

Next, the terminal C will be described. Since the base station 200 is transmitting the downlink packet A DL1 to the terminal A at the time when the terminal C transmits the uplink packet C UL, It does not receive the packet (C UL).

Accordingly, since the base station 200 that has not received the uplink packet C UL of the terminal C does not attempt to transmit the downlink packet to the terminal C, in the terminal C, the uplink packet C UL is transmitted The downlink packet reception fails even if the downlink packet reception monitoring is performed in the first downlink time interval DL1 and the second downlink time interval DL2 after the reception of the downlink packet. Uplink packet retransmission process.

For example, as shown in FIG. 2, according to the uplink packet retransmission process, the terminal C transmits the uplink packet (C UL (P)) through the channel # 2 randomly selected again at a point within the UL period Can be transmitted (retransmitted) again.

In this case, the base station 200 receives the uplink packet (C UL) from the terminal C through the channel # 2 and transmits the uplink packet (C UL) (C DL1) to the terminal C over the same channel # 2 on which the uplink packet (C UL) is received in the downlink packet (DL 1). At this point, there is no downlink packet / The downlink packet C DL1 will normally be transmitted and successfully received at the terminal C.

Next, the terminal B will be described. Since the base station 200 can simultaneously receive the uplink packets from the plurality of IoT terminals through different channels, the uplink packet from the terminal B B UL through the same channel # 1 on which the uplink packet B UL is received in the downlink time interval DL1 after 1 second based on the time when the uplink packet B UL is received It will attempt to transmit the downlink packet (B DL1) to the terminal B.

In this case, since the base station 200 is transmitting the downlink packet (C DL1) through the other channel # 2 at the time of attempting to transmit the downlink packet (B DL1), the base station (200) And will attempt to transmit downlink packet (B DL2) to terminal B over a channel (e.g., channel # 3) that is fixed to DL2 in the next second downlink time interval DL2, The downlink packet B DL2 will normally be transmitted and successfully received at the terminal B because there is no packet / uplink packet.

As described above, each of the terminals A, B, and C transmits the uplink packet (data) until it succeeds in receiving the downlink packet (response) after transmitting the uplink packet (data) due to many constraints related to the downlink transmission of the base station 200 The uplink packet transmission is uniformly repeated for every fixed UL period (P) based on the starting point of the uplink packet transmission (excluding the retransmission) although the time may be different.

2, due to a number of constraints related to downlink transmission of the base station 200, the uplink packet transmission time point or downlink packet transmission time point between terminals A, B, and C in the next UL period (P) (Case 1) in which the uplink packet / downlink packet collides due to the receivable DL1 and DL2 continuously overlapping occurs.

The continuous / repetitive packet collision situation (case 1) as described above indicates that the UEs A, B, and C uniformly repeat uplink packet transmission every fixed UL period (P) May occur continuously / repeatedly every UL period (P) unless the constraint associated with downlink transmission is changed.

However, in the current Internet (IoT) technology, there is no way to solve this situation even if a continuous / repeated packet collision situation (case 1) as described above occurs and there is no way to avoid this situation to be.

Accordingly, the present invention proposes a new scheme that avoids the above-described persistent / repetitive packet collision situations (case 1), and attempts to reduce the probability of packet collisions that may occur between IoT terminals.

More specifically, the present invention proposes a terminal device for realizing a novel scheme of the present invention.

First, a terminal device according to a preferred embodiment of the present invention will be described in detail with reference to FIG.

The terminal device 100 of the present invention corresponds to terminals A, B, and C shown in FIG. 1 described above.

The terminal device 100 of the present invention is an IoT terminal of a reception restriction type. For convenience of explanation, only the downlink time period DL1, DL2 of the fixed time (1 second) Let's assume that reception is possible.

The terminal device 100 of the present invention includes a packet transmission unit 110 for transmitting an uplink packet when a transmission time arrives, a monitoring unit 110 for monitoring downlink packet reception in a predefined downlink time interval after transmission of the uplink packet, A transmission time determiner (120) for determining a transmission time for a next uplink packet transmission based on a downlink time interval in which the downlink packet was successfully received, if the downlink packet reception is successful 130).

The packet transmission unit 110 transmits the uplink packet when the transmission time reaches the transmission time point.

Specifically, the packet transmission unit 110 randomly selects an arbitrary channel among a plurality of channels (# 0, # 1, # 2, # 3, ...) And transmits the uplink packet (data) through the channel.

The packet receiving unit 120 performs monitoring for downlink packet reception in a predefined downlink time interval after transmission of the uplink packet.

According to the reception restriction type assumed in the terminal device 100 of the present invention, the packet receiving unit 120 transmits the uplink packet after the transmission of the uplink packet, DL1 to monitor downlink packet reception monitoring.

If the downlink packet reception is successful in DL1, the packet receiving unit 120 waits until the packet transmission unit 110 transmits the next uplink packet. When the downlink packet is not received in DL1, The downlink packet reception monitoring is performed in the second downlink time interval (DL2) after 3 seconds based on the completion time of the uplink packet transmission.

If the downlink packet reception is successful in DL2, the packet receiving unit 120 waits until the packet transmission unit 110 transmits the next uplink packet. In DL2, the downlink packet reception failure And allows the packet transmission unit 110 to perform an uplink packet (data) retransmission process.

When the downlink packet reception is successful, the transmission time determination unit 130 determines the transmission time point for the next uplink packet transmission based on the downlink time interval in which the downlink packet reception was successful.

Specifically, the transmission time determining unit 130 determines the transmission time point of the uplink time interval, the uplink time interval, and the first downlink time interval, which are used for the transmission of the uplink packet, A specific time calculated based on at least one of a time interval and a predefined uplink transmission period may be determined as a transmission time point for the next uplink packet transmission.

Here, the start time of the downlink time slot in which the downlink packet reception is successful means the start time of DL1 if the downlink packet reception is successful in DL1, and the start time of DL2 if the downlink packet reception is successful in DL2 it means.

The uplink time interval used for the uplink packet transmission means the time (L) required for transmitting the uplink packet transmitted by the packet receiving unit 120 immediately before. According to the assumed reception restriction type, it can be 1 second.

Therefore, in the following description, it is assumed that the uplink time interval (UL = L) is 1 second for convenience of explanation.

The time interval between the uplink time interval UL and the first downlink time interval DL1 is a time interval M between the completion time at which the uplink packet transmission is completed, that is, the end time of the UL and the start time of DL1, And may be one second according to the reception restriction type assumed in the terminal device 100 of the present invention.

Therefore, for convenience of explanation, it will be assumed below that the time interval M between UL and DL1 is 1 second.

The predefined uplink transmission period means the above-described UL period (P).

The transmission time determination unit 130 determines the time interval (M = 1 second) between the start point of DL1, UL (L = 1 second), UL and DL1, assuming that the downlink packet reception is successful in DL1. , And the UL period (P), as the transmission time point for the next uplink packet transmission.

More specifically, assuming that the downlink packet reception is successful in DL1, the transmission time determining unit 130 determines UL (L = 1 second) from the point in time at which the UL period (P) And the time interval (M = 1 second) between the UL / DL1, as the transmission time point for the next uplink packet transmission.

Therefore, if the start point of DL1 or DL2 succeeding in downlink packet reception is K, the transmission time point T _{next UL} for the next uplink packet transmission can be determined according to Equation (1).

As can be seen from Equation (1), the time interval between the UL period (P), UL (L = 1 second), and UL / DL1 is a fixed constant value, , The transmission time point T _{next UL} for the next uplink packet transmission depends on whether the downlink time interval in which the reception of the downlink packet successfully succeeds is a downlink time interval, that is, DL1 or DL2.

More specifically, due to a K value that varies depending on whether the downlink time interval in which the reception of the downlink packet has succeeded is a certain downlink time interval, that is, DL1 or DL2, (T _{next UL} ) for link packet transmission is changed.

The transmission time determination unit 130 determines the transmission time T _{next UL} for transmission of the _{next uplink} packet and shares it with the packet transmission unit 110.

The packet transmission unit 110 transmits a plurality of channels (# 0, # 1, # 2, # 3,...) At the transmission time point T _{next UL} determined by the transmission time decision unit 130 after transmitting the uplink packet. ...) and randomly selects an arbitrary channel and transmits the uplink packet (data) through the selected channel (except for retransmission).

Of course, the packet receiving unit 120 performs downlink packet reception monitoring at DL1 and DL2 based on the completion time of transmission of the uplink packet transmitted at the transmission time T _{next UL} , A process of determining a transmission time T _{next UL} for transmission of the next uplink packet based on the DL1 or DL2 succeeding the packet reception and sharing with the packet transmission unit 110 will be repeated every time the uplink packet is transmitted.

As described above, the terminal device 100 of the present invention is able to determine the downlink time of the success of the downlink packet reception, which may vary depending on coexisting IoT terminals, due to many constraints related to the downlink transmission of the base station 200 (T _{next UL} ) for the _next uplink packet transmission based on the interval (e.g., DL1 or DL2) is repeated every time the uplink packet is transmitted, so that the uplink packet transmission is performed at an irregular time interval It becomes possible to repeat.

As a result, in the present invention, unlike the conventional method in which the uplink packet transmission is uniformly repeated every fixed UL period (P) of the IoT terminal (e.g., the terminals A, B, and C) A new method of determining the transmission time T _{next UL} each time is differently implemented and the uplink packet transmission is irregularly performed to avoid the continuous / repeated packet collision situation (case 1).

Referring to FIG. 4, a case in which a continuous / repeated packet collision situation is avoided and the possibility of packet collision is lowered according to the present invention will be described.

For convenience of explanation, the terminals A, B, and C of the reception restriction type will be described as the IoT terminal.

4, each of the terminals A, B, and C transmits an uplink signal through an arbitrarily selected channel among a plurality of channels (# 0, # 1, # 2, # 3, Link packet.

In FIG. 4, for convenience of explanation, the situation is shown in the same manner as that shown in FIG. 2 based on the time sequence.

That is, the terminal A first transmits the uplink packet (A UL) through the channel # 0, the next terminal C transmits the uplink packet (C UL) through the channel # 3, And transmits the uplink packet (B UL) via the uplink packet (B UL).

First, the base station 200 receives the uplink packet (A UL) from the terminal A through the channel # 0, and transmits the downlink packet (DL) from the DL 1 to the terminal A through the same channel # 0 A DL1), and this downlink packet A DL1 will normally be transmitted and successfully received at terminal A. At this time, A_DL1 (1) means the start time of DL1 in which the downlink packet A DL1 has been successfully received.

In this case, instead of the conventional scheme of transmitting the next uplink packet after the elapse of the UL period (P), the terminal A of the present invention transmits the transmission time point (Tnext _UL = A_DL1 (1)) determined based on DL1, + PLM). &Lt; / RTI &gt;

Next, the terminal C will be described. Since the base station 200 is transmitting the downlink packet A DL1 to the terminal A at the time when the terminal C transmits the uplink packet C UL, It does not receive the packet (C UL).

Therefore, in the case of the terminal C, even if downlink packet reception monitoring is performed in DL1 and DL2 after transmitting the uplink packet (C UL), the downlink packet reception fails, and according to a predetermined rule within the UL period (P) And perform an uplink packet retransmission process at a time point.

For example, as shown in FIG. 4, according to the uplink packet retransmission process, the terminal C transmits the uplink packet (C UL (P)) through the channel # 2 randomly selected again at a point within the UL period Can be transmitted (retransmitted) again.

In this case, the base station 200 receives the uplink packet C UL from the terminal C through the channel # 2 and tries to transmit the downlink packet C DL1 from the DL 1 to the terminal C through the same channel # 2 And this downlink packet C DL1 will normally be transmitted and successfully received at terminal C, At this time, C_DL1 (1) means the start time of DL1 in which the downlink packet C DL1 has been successfully received.

In this case, the terminal C of the present invention uses the transmission time (Tnext _UL = C_DL1 (1)) determined based on the DL1 of success of the downlink packet reception instead of the conventional method of transmitting the next uplink packet after the elapse of the UL period (P) + PLM). &Lt; / RTI &gt;

Next, the terminal B will be described. The base station 200 receives the uplink packet (B UL) from the terminal B through the channel # 1 and transmits the downlink packet B DL1).

In this case, since the base station 200 is transmitting the downlink packet (C DL1) through the other channel # 2 at the time of attempting to transmit the downlink packet (B DL1), the base station (200) And will attempt to transmit a downlink packet (B DL2) to terminal B over a channel (e. G., Channel # 3) fixed at DL 2 in DL 2 and this downlink packet (B DL2) Lt; / RTI &gt; At this time, B_DL2 (1) means the start time of DL2 in which the downlink packet C DL2 is successfully received.

In this case, the terminal B of the present invention uses the transmission time (Tnext _UL = B_DL2 (1)) determined based on the DL2 of the success of downlink packet reception instead of the conventional scheme of transmitting the next uplink packet after the elapse of the UL period (P) + PLM). &Lt; / RTI &gt;

As described above, according to the present invention, each of the terminals A, B, and C transmits a downlink packet reception success downlink signal, which may be different due to many constraints related to downlink transmission of the base station 200 and coexistent other IoT terminals. (Changes) the transmission time (Tnext UL) for the next uplink packet transmission based on the link time interval (e.g., DL1 or DL2).

2 and FIG. 4, DL1 and DL2 capable of receiving uplink packets or receiving downlink packets between the terminals A, B and C in the UL period P are overlapped in the same manner as the uplink packet / down According to the present invention, the uplink packet transmission in each of the terminals A, B and C is performed at irregular time intervals, so that the terminals A, B, It can be seen that DL1 and DL2 capable of receiving an uplink packet or DL1 and DL2 capable of receiving a downlink packet do not overlap in the same manner, thereby avoiding a continuous / repeated packet collision case (Case 1) naturally.

As described above, according to the present invention, it is possible to realize a new scheme in which the IoT terminal determines the transmission time (T _{next UL} ) for the _next uplink packet transmission every time differently, thereby performing uplink packet transmission irregularly, It is possible to reduce the possibility of packet collision by avoiding the continuous / repetitive packet collision situation, and further to improve the quality of the Internet (IoT) service.

Hereinafter, with reference to FIG. 5, an uplink packet transmission method of a terminal apparatus according to a preferred embodiment of the present invention will be described.

In the following description, for convenience of explanation, the base station 200 will be described in the same manner as the above-described embodiment, and the terminal device 100 of the present invention may correspond to each of the terminals A, B and C, respectively.

The terminal device 100 performs a radio section connection with the base station 200 (S100), and then performs the following steps for continuously transmitting data.

The uplink packet transmission method of the terminal device 100 according to the present invention randomly selects an arbitrary channel among a plurality of channels (# 0, # 1, # 2, # 3 ...) , And transmits the uplink packet (data) through the selected channel (S110).

Accordingly, in order to receive a downlink packet (response) for the transmitted uplink packet (data), the uplink packet transmission method of the terminal device 100 according to the present invention is configured to transmit a downlink packet The downlink packet reception monitoring is performed through the same channel as the channel in which the uplink packet is transmitted in DL1.

Specifically, assuming that an uplink packet is transmitted through the channel # 0, the uplink packet transmission method of the terminal device 100 according to the present invention restarts the timer 2 from 0 (S120), and recognizes the elapsed time based on the completion time of the uplink packet transmission (end point of UL).

The uplink packet transmission method of the terminal device 100 according to the present invention is such that when 1 second elapses based on the end point of the UL based on the timer 2 (S130 Yes), the uplink packet transmission method of the downlink packet Monitoring for reception is performed (S150).

In the uplink packet transmission method of the terminal 100 according to the present invention, the timer 1 is restarted at 0 (S140) when 1 second has elapsed based on the end point of the UL (Yes in S130) And recognizes the elapsed time based on the downlink time interval for performing the monitoring, that is, the starting point of DL1.

The uplink packet transmission method of the terminal device 100 according to the present invention is a method in which UL (L = 1 sec) is transmitted in the UL period (P) based on the timer 1 when the downlink packet reception is successful in DL1 And a time (P-1-1) obtained by subtracting a time interval (M = 1 second) between UL / DL1 is elapsed (S210).

Since timer 1 restarts to zero at the time point at which DL1 starts monitoring for receiving a downlink packet through channel # 0, that is, at the start of DL1, timer 1 is reset to UL (P) based on timer 1, (P-1-1), which is obtained by subtracting the time interval (M = 1 second) between the UL / DL1 from the UL period (L = 1 sec) ( _{Tnew UL} ) for the next uplink packet transmission determined in the present invention by a time interval (M = 1 second) between the UL (L = 1 second) and the UL / will be.

If it is determined in step S210 that the time (P-1-1) has elapsed (S210), the uplink packet transmission method of the terminal device 100 according to the present invention transmits the uplink packet, At step S110, the BS transmits an uplink packet (data) to the UE at a time point ( _{Tnext UL} ).

On the other hand, in the uplink packet transmission method of the terminal device 100 according to the present invention, when no downlink packet is received in DL1 (No in S160), when 3 seconds have elapsed based on the end point of UL based on the timer 2 (S170 Yes), monitoring for downlink packet reception is performed through a channel (e.g., channel # 3) fixed to DL2 in DL2 (S190).

In the uplink packet transmission method of the terminal 100 according to the present invention, when 3 seconds have elapsed based on the end point of the UL (Yes in S170), the timer 1 is restarted at 0 (S180) And recognizes the elapsed time based on the downlink time interval for performing the monitoring, that is, the starting point of DL2.

The uplink packet transmission method of the terminal device 100 according to the present invention is a method in which UL (L = 1 second) in the UL period (P) based on the timer 1 when the downlink packet reception is successful in the DL2 And a time (P-1-1) obtained by subtracting a time interval (M = 1 second) between UL / DL1 is elapsed (S210).

At this time, the timer 1 restarts to zero at the time point at which DL2 starts monitoring for reception of the downlink packet through channel # 3, that is, at the start point of DL2. Therefore, The time point when it is determined that the time (P-1-1) elapsed after subtracting the time interval (M = 1 second) between the UL (L = 1 second) and the UL / DL1 elapses is determined as the UL period (P) transmission time for the next uplink packet transmission to that is a point in time earlier by a time interval (M = 1 second) between UL (L = 1 second), and UL / DL1 determined in the present invention, from the elapsed time by (T _{next UL} )would.

If it is determined in step S210 that the time (P-1-1) has elapsed (S210), the uplink packet transmission method of the terminal device 100 according to the present invention transmits the uplink packet, At step S110, the BS transmits an uplink packet (data) to the UE at a time point ( _{Tnext UL} ).

5, since the terminal device 100 of the present invention will repeatedly transmit data (uplink packet) as the IoT terminal, the termination step is not shown. However, in the case where the terminal device 100 is turned off Even at this point in time, the operation of each step will be terminated.

As described above, according to the present invention, the IoT terminal realizes a new scheme for determining the transmission time (T _{next UL} ) for the _next uplink packet transmission every time differently, thereby irregularly performing uplink packet transmission, It is possible to reduce the possibility of packet collision by avoiding a continuous / repeated packet collision situation that may occur between the mobile station and the mobile station, and further improve the quality of the Internet service (IoT).

The uplink packet transmission method according to an embodiment of the present invention can be implemented in the form of a program command that can be executed through various computer means and recorded in a computer readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

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, 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 as defined by the appended claims.

According to the terminal apparatus of the present invention and the uplink packet transmission method performed by the apparatus, it is possible to realize a new scheme capable of reducing the possibility of packet collision avoiding persistent / repetitive packet collision situations that may occur between IoT terminals Is an invention that is industrially applicable because it is beyond the limit of the existing technology, and it is not only the use of the related technology but also the possibility of commercialization or operation of the applicable device,

100: terminal device
110: Packet transmission unit 120: Packet reception unit
130:
200: base station

Claims (9)

A packet transmitter for transmitting an uplink packet when a transmission time arrives;
A packet receiver for performing monitoring for downlink packet reception in a downlink time interval defined before transmission of the uplink packet; And
And a transmission time determiner for determining a transmission time for the next uplink packet transmission based on a downlink time interval in which the downlink packet reception was successful, when the downlink packet reception is successful. The method according to claim 1,
The terminal apparatus comprises:
Wherein after the transmission of the uplink packet, the downlink packet for the uplink packet is received only in a downlink time interval of a predetermined number of times. 3. The method of claim 2,
The transmission time determination unit may determine,
An uplink time interval used for uplink packet transmission, a time interval between the uplink time interval and the first downlink time interval, a time interval between the start time of the downlink packet reception succeeding in the downlink packet reception, At a specific time calculated on at least one basis,
And determines a transmission time point for transmission of the next uplink packet. The method of claim 3,
The transmission time determination unit may determine,
The uplink time interval and the specific time point prior to the time interval from a point in time when the uplink transmission period has elapsed from the start point of the downlink time interval in which the downlink packet reception was successful,
And determines a transmission time point for transmission of the next uplink packet. 3. The method of claim 2,
Wherein the transmission time point for the next uplink packet transmission is a time point,
And a downlink time interval in which the reception of the downlink packet is successful depends on a number of downlink time intervals of the specific number. A packet transmission step of transmitting an uplink packet when a transmission time arrives;
Performing a monitoring for downlink packet reception in a downlink time interval defined before transmission of the uplink packet; And
And determining a transmission time point for the next uplink packet transmission based on a downlink time interval in which the downlink packet reception was successful when the downlink packet reception is successful. Link packet transmission method. The method according to claim 6,
The terminal apparatus comprises:
And after the transmission of the uplink packet, the downlink packet for the uplink packet can be received only in a downlink time interval of a predetermined number of times. 8. The method of claim 7,
The transmission time determination step may include:
An uplink time interval used for uplink packet transmission, a time interval between the uplink time interval and the first downlink time interval, a time interval between the start time of the downlink packet reception succeeding in the downlink packet reception, At a specific time calculated on at least one basis,
And determines a transmission time point for the next uplink packet transmission. 9. The method of claim 8,
The transmission time determination step may include:
The uplink time interval and the specific time point prior to the time interval from a point in time when the uplink transmission period has elapsed from the start point of the downlink time interval in which the downlink packet reception was successful,
And determines a transmission time point for the next uplink packet transmission.

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