TWI519197B - Device-to-device communication devices, systems and related device-to-device wireless communications methods - Google Patents

Description

Communication device and system for performing device-to-device communication and device thereof Method for wireless communication of devices

The disclosure relates to a method for wireless communication of a device, a system, and a related device thereof that can perform device-to-device communication.

In a typical wireless communication system, a user equipment (User Equipment, UE) can perform wireless communication of voice and/or data services through a base station and a service network, wherein wireless communication between the user equipment and the service network is performed. Can be based on a variety of wireless technologies, such as: Global System for Mobile communications (GSM) technology, General Packet Radio Service (GPRS) technology, Enhanced Data rates for (Enhanced Data rates for Global Evolution, EDGE) technology, Wideband Code Division Multiple Access (WCDMA) technology, Code Division Multiple Access 2000 (CDMA 2000) technology, time-sharing synchronous code division Time Division-Synchronous Code Division Multiple Access (TD-SCDMA) technology, global interoperability microwave Wor1dwide Interoperability for Microwave Access (WiMAX) technology, Long Term Evolution (LTE) technology, Advanced LTE-Advanced (LTE-A) technology, and the like.

As the next generation of wireless communication systems, the Third Generation Partnership Project (3GPP) LTE can provide relevant technologies for high data rates and high system capacity. In addition, LTE-A is defined to support new components to LTE so that it can meet higher communication requirements. Device-to-Device (hereinafter referred to as D2D) communication is a technical component for LTE-A. D2D communication can allow two or more devices in proximity to each other, which can be called proximity devices/neighboring devices, to form an ad hoc network or through autonomous methods. A base station coordinates to establish a direct local connection for mutual communication and/or direct data transmission.

However, before the concept of D2D communication can be implemented and commercialized, there are many things that must be considered first. One of the things to consider is how to find devices close to each other. Recently, 3GPP has proposed research on the proximity service (Prose) for D2D communication in LTE wireless communication systems. However, in the research of existing LTE wireless communication systems, it is rare to propose a solution for distributed D2D proximity discovery. In addition, in existing LTE wireless communication systems, different signal messages must be used to find D2D devices with sufficient strength, to find D2D devices with the same application preferences and/or requirements, and to use different D2D devices. Synchronize between.

In view of this, an embodiment of the present disclosure provides a communication device and system for performing device-to-device communication and a method for the device to wirelessly communicate with the device.

An embodiment of the present disclosure provides a communication device that can perform wireless communication with a device of a first proximity communication device. The communication device includes a wireless module, a counter and a controller module. The wireless module performs wireless transmission and reception. The counter has a count value and a threshold value. The controller module determines whether to transmit the proximity signal through the wireless module according to the comparison result between the count value and the threshold value. When the count value reaches the threshold value, the controller module determines to send a broadcast through the wireless module. The first proximity signal is transmitted to the first proximity communication device, and wherein the counter value is changed according to one of the second proximity signals broadcasted by the first proximity communication device.

An embodiment of the present disclosure further provides a device-to-device communication system for performing wireless communication between a device and a device, comprising at least a first communication device and a second communication device, wherein each of the first communication device and the second communication device The utility model comprises a wireless module for performing wireless transmission and reception, a counter having a count value and a threshold value, and a controller module. The controller module determines whether to transmit the proximity signal through the wireless module according to the comparison result between the count value and the threshold value, wherein the controller module of the first communication device is connected to the count value corresponding to the first communication device. When the threshold value is reached, it is determined that the wireless module that is transmitted through the first communication device broadcasts a first proximity signal to the second communication device, and wherein the count value corresponding to the first communication device is based on the second One of the second proximity signals transmitted by the communication device is changed.

An embodiment of the present disclosure further provides a device-to-device wireless communication method, which is applicable to a device-to-device communication system, including at least one first pass. And the second communication device includes the following steps: the first communication device determines whether to broadcast a first proximity according to a comparison result between a counter value corresponding to one of the counters of the first communication device and a threshold value Signaling to the second communication device; and when the count value corresponding to the first communication device reaches the threshold, the first communication device determines to broadcast the first proximity signal to the second communication device, wherein the first communication device corresponds to the count value The change is generated according to one of the second proximity signals broadcasted by the second communication device.

With respect to other additional features and advantages of the present invention, those skilled in the art can wirelessly communicate with the device communication device and related devices according to the device disclosed in the present invention without departing from the spirit and scope of the present disclosure. The method is done with a little change and retouching.

The above and other objects, features, and advantages of the present invention will become more apparent and understood.

100‧‧‧Device-to-device communication system

110‧‧‧Communication device

112‧‧‧Wireless Module

114‧‧‧Controller Module

116‧‧‧ counter

120, 130, 140‧‧‧ communication devices

200‧‧‧Service Network

212‧‧‧Base station

S202, S204, ..., S210‧‧ steps

S302, S304‧‧‧ steps

Code#1-Code#5‧‧‧ Random Access Channel Code

400‧‧‧Form

UE, UE#1-UE#4‧‧‧ user device

S502, S504, S506, S508‧‧‧ steps

T0-t3‧‧‧Time

S602, S604‧‧‧ steps

Signal_Blue, Signal_Red‧‧‧ proximity signals

1 shows a schematic diagram of a D2D communication system in accordance with an embodiment of the present disclosure.

FIG. 2 is a flow chart showing a D2D communication method for proximity discovery on a D2D communication system according to an embodiment of the present disclosure.

FIG. 3A is a flow chart showing a D2D communication method according to an embodiment of the present disclosure, in which a D2D device is configured in a trigger procedure of the D2D communication system.

FIG. 3B is a diagram showing the designation of a random access channel code or a preamble of a neighboring signal according to an embodiment of the present disclosure.

FIG. 3C shows an example of different D2D UE groups according to an embodiment of the present disclosure. Schematic diagram of resource allocation scenarios.

Figure 4 is a diagram showing a table showing changes in the count value between D2D devices in a D2D group in a synchronization program according to an embodiment of the present disclosure.

FIG. 5A is a flow chart showing a hold connection procedure in accordance with an embodiment of the present disclosure.

FIG. 5B is a diagram showing a mechanism for maintaining a connection signaling according to an embodiment of the present disclosure.

Figure 6A shows a flow chart of a triggering procedure in accordance with an embodiment of the present disclosure. as well as

FIG. 6B is a schematic diagram showing a trigger mechanism according to an embodiment of the present disclosure.

The above and other objects, features, and advantages of the present invention will become more apparent and understood from the <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; Before the concept can be implemented and commercialized, there are many things that must be considered first. One of the things to consider is how to find devices close to each other. Proximity discovery can be classified into physical communication level proximity discovery and application level proximity discovery. Proximity discovery at the physical communication level focuses on the connection of wireless communication. Assuming that two D2D devices can discover each other or exchange wireless signals between each other, the two D2D devices can be considered "in proximity". Application-level proximity discovery focuses on the application's preferences, where sharing the same D2D device that favors a particular application can be considered "proximity."

Since it can reduce the signaling process, it needs to be integrated. The two adjacent proximity methods described above. For example, the proximity discovery request signal at the physical communication level can be exchanged between different D2D devices. This is to ensure that these D2D devices are geographically adjacent and capable of exchanging messaging messages. In addition, timing alignment can also be forced in order to exchange signals between D2D devices. Application-level proximity discovery requires D2D devices to find other D2D devices with the same preferences. In general, such D2D devices will execute the same application and are also willing to establish connections with other D2D devices. The two cases mentioned above can be viewed as synchronizing at the entity or application level, which will generate a large number of message messages.

Therefore, an embodiment of the present disclosure provides a method for performing proximity discovery in a D2D communication environment, which can achieve application level transmission by transmitting and detecting proximity signals between different D2D devices of a D2D communication system. Proximity to the purpose of discovery. In addition to being used for proximity discovery, an embodiment of the present disclosure may be further used to facilitate synchronization between D2D devices, maintain an Alive of D2D devices, or trigger application or data transfer between D2D devices. The wireless communication system suitable for the D2D communication of the present disclosure is not limited to the mobile user device, and the fixed user device is still applicable.

1 shows a schematic diagram of a D2D communication system 100 in accordance with an embodiment of the present disclosure. In the D2D communication system 100, the communication device 110 is wirelessly connected to the base station 212 of the service network 200 through a spatial interface to obtain wireless access services. In general, communication device 110, also referred to as user equipment (UE), and base station 212 can be a base station or an access station, or an evolved base station (eNB) of a long term evolution system. In this embodiment, the communication device 110 can be a device with D2D communication capability, which is a device that can support D2D communication and can perform D2D communication with other devices 120-140 or systems with D2D communication capabilities. communication The devices 120-140 are D2D communication capable devices having a communication hardware architecture and functions similar to those of the communication device 110, and the communication devices 120-140 are in proximity to the communication device 110, and thus may be referred to as communication devices. 110 proximity devices (proximity devices/neighboring devices). The communication device 110 can include a wireless module 112 that performs wireless transmission and reception with the base station 212 or other devices having D2D communication capabilities. The wireless module 112 can further include a baseband unit (not shown) and a radio frequency (RF) module (not shown). The baseband unit can include multiple hardware devices to perform the fundamental frequency. Signal processing, including analog to digital conversion (ADC) / digital to analog conversion (DAC), gain adjustment, modulation and demodulation, and encoding / decoding. The RF module can receive the RF wireless signal, convert the RF wireless signal into a baseband signal for further processing by the baseband module, or receive the baseband signal from the baseband signal module, and convert the baseband signal into a radio frequency wireless Signal for transmission. The RF module may also include a plurality of hardware devices to perform the above-described RF conversion. For example, the RF module may include a mixer to multiply the baseband signal by one of the RF carriers of the communication system. The radio frequency may be 900 MHz, 1900 MHz, or 2100 MHz used by the wideband code division multiplexing access system, or 900 MHz, 2100 MHz, or 2600 MHz used by the Long Term Evolution system, or other wireless access technologies. The standard depends. In addition, the communication device 110 further includes a controller module 114, and controls the wireless module 112 and other functional modules (for example, a display unit and/or a keypad for providing a human-machine interface, and a code for storing an application and a communication protocol). The operational status of the storage unit, etc.). The service network 200 can include a control node that controls the operation of at least one access node. The operation of the service network 200 can be followed A communication agreement. In an embodiment, the service network 200 may be a long-term evolution system network, and the communication device 110 may be a user device according to one of the specifications of the long-term evolution technology, and the disclosure is not limited thereto. In addition, the communication device 110 may further include a counter 116 to determine whether a broadcast transmission or a broadcast transmission of the proximity signal to other devices having D2D communication capabilities is required. The counter 116 can have a count value and a threshold value, wherein the count value can be incremented over time (eg, each time slot is incremented by a predetermined amount), and the threshold value is set for the counter 116. For example, the counter 116 can be implemented by a decentralized counter or an integrator, etc., but the disclosure is not limited thereto. Among them, the rate of increase of the counter value of different D2D devices may also be different. A device that detects a neighboring signal will increment the counter corresponding to its counter by a predetermined/fixed number. When the counter count of a D2D device reaches the threshold, the D2D device will broadcast the proximity signal, and after the neighbor signal is sent, the counter value of the reset counter is zero. The proximity signals are then broadcasted to the adjacent D2D devices to increase the count values corresponding to the adjacent D2D devices. In some embodiments, the value increase rate and the threshold value of the counters of all D2D devices can be set to be different. The broadcast transmission and detection procedures of the aforementioned proximity signals will continue until the signal broadcast transmission periods of all D2D devices are synchronized.

For example, the controller module 114 controls the wireless module 112 to perform a proximity discovery process with other neighboring D2D devices for D2D communication.

In some embodiments, the controller module 114 can determine to broadcast a first proximity signal to a first proximity communication device (eg, the communication device 120) through the wireless module 112 when the count value reaches the set threshold. , wherein the counter value is based on the first proximity communication device (proximity A second proximity signal sent by the communication devices/neighboring communication devices is changed. The controller module 114 can further detect that it is adjacent to the first proximity communication device when receiving the second proximity signal sent by the first proximity communication device. In an embodiment, the first and second neighboring signals may be the same neighboring signal or may be different neighboring signals.

FIG. 2 is a flow chart showing a D2D communication method for proximity discovery on a D2D communication system according to an embodiment of the present disclosure. In this embodiment, the D2D communication method can be applied to each communication device in the D2D communication system 100 shown in FIG. 1, wherein the wireless module 112 is executed with a network entity (for example, a base station). 212) or wireless transmission and reception between other neighboring devices. In this embodiment, it is assumed that the count value of the counter 116 is initially set to zero.

First, in step S202, the controller module 114 periodically increments the count value of the counter 116 by a predetermined amount with time and then continuously detects whether there is a broadcast to send or receive/receive any proximity as a step S204. Signal. For example, its count value is incremented at a fixed rate over time (eg, each time slot is incremented by a given number "1"). When the controller module 114 receives a received signal sent from another neighboring device (for example, the communication device 130) (YES in step S204), in step S206, the controller module 114 receives/detects each The proximity signal performs an operation of incrementing the count value of the counter 116 by a second predetermined number. For example, assuming that the first predetermined number is set to 1 and the second predetermined number is set to 3, when the controller module 114 receives a proximity signal from one of the neighboring devices, the count value will change from 0 to 4. And when the controller module 114 is simultaneously When two adjacent signals are received from two of the neighboring devices, the count value will change from 0 to 7. Then, the controller module 114 further determines whether to transmit the proximity signal according to the comparison result between the count value and the threshold value. In step S208, the controller module 114 further determines whether the count value of the counter 116 has exceeded the threshold. When the count value has not exceeded the threshold value (No in step S208), it indicates that no reception signal will be broadcasted, and the controller module 114 then returns to step S202 to perform subsequent counter value increment. When the count value reaches the threshold (Yes in step S208), in step S210, the controller module 114 broadcasts the proximity signal, and resets the counter value to 0 after the signal is sent. When the counter is reset to zero, the controller module 114 then returns to step S202 for subsequent counter value increments. When other devices (for example, the communication devices 120-140) detect the proximity signals broadcast by the communication device 110, if they are also executing or prefer the same application that the communication device 110 executes or prefers, / Fixed number increments the count value of its corresponding counter. It can be understood that, assuming that the communication device 130 can receive or detect the proximity signal sent by the communication device 110, the communication device 130 must be adjacent to the communication device 110. Similarly, if the communication device 110 can receive or detect the proximity signal sent by the communication device 130, the communication device 110 must be adjacent to the communication device 130. Therefore, when receiving the proximity signal sent by the communication device 130, the communication device 110 detects that the communication device 130 is adjacent to the communication device 130.

In the foregoing embodiment, the controller module 114 may increment the count value according to pre-installed setting parameters stored in the storage unit of the communication device 110. In some embodiments, the D2D communication system 100 can further provide a network entity to manage or set all D2D devices in the D2D communication system 100, and the controller module Group 114 can increment its count value based on the message sent by the network entity. The network entity may be a serving base station (eg, base station 212) of the communication device 110, an MME, or a specific node in the service network 200. The network entity (for example, the base station 212 or the MME) can also facilitate the network settings in the operations (for example, proximity signal designation and radio resource configuration, etc.) provided by an embodiment of the present disclosure.

FIG. 3A is a flow chart showing a D2D communication method according to an embodiment of the present disclosure, in which a D2D device is configured in a triggering procedure of the D2D communication system. In this embodiment, the triggering procedure can be applied to each of the communication devices in the D2D communication system 100, such as the communication device 110 shown in FIG. When the controller module 114 of the communication device 110 receives the configuration request including the configuration data from the network entity through the wireless module 112 (step S302), the controller module 114 first obtains the configuration data included in the configuration request. The configuration data is then applied to the communication device 110 (step S304). Thereafter, the controller module 114 uses the applied configuration data to continue the aforementioned detection and counter value incrementing process.

In an embodiment, the network entity may configure encoding or preambles for proximity signal transmission. In this embodiment, the network entity may further configure a first proximity signal to a first group of communication devices and a second proximity signal to a second group of communication devices, where the first group of communications The device requests a first service and the communication device of the second group to request a second service, and the first proximity signal and the second proximity signal are two using different Random Access CHannel (RACH) codes. Signal. FIG. 3B is a diagram showing the designation of a random access channel code or a preamble of a neighboring signal according to an embodiment of the present disclosure. In some embodiments, the proximity signal can pass other signaling mechanisms, such as a CDMA code, a specific RF signal type. (pattern) or other identifiable signals, etc. to achieve. The network entity can also configure different random access channel codes for use by a particular D2D group. For example, in this embodiment, different groups specify different encodings. In addition, two or more encodings can be assigned to the same group to assist in physical layer synchronization and triggering of application events. As shown in FIG. 3B, the network entity can respectively set a RACH code code#1 and a RACH code code#3 for the physical layer synchronization of the first UE group #1 and the triggering use of the application event, setting one. The RACH code code#2 is used for synchronization of the physical layer of the second UE group #2, and a RACH code code#4 and a RACH code code#5 are respectively set for synchronization of the physical layer of the third UE group #3. Triggered with application events. The network entity can register and manage a code-interest mapping information in a web server/database (not shown) (eg, which code is used to record which code is used) Indicates which kind of application preference information). That is to say, the matching information record of the encoding and the application preference has a correspondence between different services and RACH codes or a correspondence between different services and their corresponding RACH resources. For example, the matching information of the encoding and the application preference may record that the RACH code #1 corresponds to a first application, the RACH code #2 corresponds to a second application, and the like.

In another embodiment, the network entity may also manage and configure radio resources (eg, RACH resources) to periodically transmit neighboring signals. In this embodiment, the network entity may further configure a first proximity signal to the communication device of the first group and a second proximity signal to the communication device of the second group, where the communication device of the first group Requesting a first service through a first resource and the communication device of the second group to request a second service through a second resource The first resource and the second resource are different RACH resources. For example, in some embodiments, different groups may be configured to use different radio resources in order to reduce power consumption of random access codes or preambles, as shown in FIG. 3C. FIG. 3C is a schematic diagram showing a resource configuration situation between different D2D UE groups according to an embodiment of the disclosure. As shown in FIG. 3C, the network entity may separately set a RACH code code#1 and a RACH code code#3 for the D2D device in the first UE group #1 to perform physical layer synchronization and application by using the first carrier. Trigger of program events. The network entity may further set the same RACH code code#1 for the D2D device in the second UE group #2 and the D2D device in the third UE group #3 to transmit the second carrier and the third carrier respectively. The physical layer is synchronized.

The network entity (e.g., base station 212) can further adjust the synchronization policies and parameters used by the D2D communication system 100. The network entity can assign policies and/or settings for synchronization through a control command channel (eg, the control command channel can be a broadcast channel or a unicast control channel). For example, the network entity adjustable example parameters may include: a formula for calculating a counter, a parameter of an acceleration or deceleration synchronization program, a criterion for triggering transmission of a neighboring signal, an adjustment amount of a count value after transmitting a neighboring signal, and a count value. The periodic adjustment amount (for example, the counter can be incremented by a value of Parameter_Increment per second), but the disclosure is not limited thereto.

When no settings are required, the network entity (e.g., base station 212) is in an idle (IDLE) state. When the D2D communication system 100 having the D2D device employing the mechanism proposed by the present disclosure needs to be set, the network entity can assign setting data to one or more devices in the D2D device to set some or all of the D2D devices. After completing the set assignment, the network entity will return to idle status. The foregoing settings may be performed offline, at the beginning of the service, or dynamically before the service begins to provide an adaptive operation. In addition, the policies, parameter settings, or code assignments specified by the network entity can be maintained or updated during operation.

As mentioned above, in addition to proximity discovery, the D2D communication method of the present disclosure can also assist in synchronizing between D2D devices, maintaining connections to D2D devices, or triggering applications or transmissions between D2D devices after synchronization of a group of D2D devices. . In one embodiment, D2D devices that use the same proximity signal will be classified into one same group.

In an exemplary embodiment, the present disclosure provides a synchronization mechanism for a D2D communication system (eg, D2D communication system 100). The synchronization between the D2D devices (for example, the communication devices 110-140) can be achieved by synchronizing the transmission and reception timings of the adjacent signals used by the D2D device. Each D2D device can transmit a proximity signal to its neighbors separately for use as proximity discovery and synchronization. The proximity signal may, for example, be transmitted in a periodic manner, or the proximity signal may be transmitted according to a count value of a D2D device or when a proximity signal is received. Each D2D device can utilize a counter to determine when a proximity signal should be transmitted. In some embodiments, the counter's count value may be incremented periodically or may be changed upon receipt of a neighboring signal from another device. The D2D device can transmit a proximity signal according to the count value. For example, the D2D device may send a proximity signal when the count value reaches the threshold, or may decrease the count value by a specific constant value or reset the count value to 0 after sending a proximity signal.

In some embodiments, the communication device 110 synchronizes with the first proximity communication device (eg, the communication device 120) by using a third signal, so that the communication device 110 and the first proximity communication device can simultaneously be the third proximity signal.

4 is a diagram showing a table 400 in accordance with an embodiment of the present disclosure, wherein the table 400 represents a change in the count value of the communication device (or may be referred to as a D2D device) UE#1-UE#3 in the synchronization procedure. In this embodiment, it is assumed that there are three D2D devices UE#1, UE#2 and UE#3 that use the same neighboring signal and are not synchronized at the initial time, wherein the threshold value of each counter is set to a predetermined value of 10 and is not When any signal is received, the phase increment rate of the counter is set to 1 for each time slot. In addition, the increment of the counter is set to a predetermined value of 3 each time a neighboring signal is received.

As shown in FIG. 4, when the synchronization procedure starts, the values of the counters of the three D2D devices UE#1, UE#2, and UE#3 are 2, 8, and 9, respectively. Obviously, these three D2D devices have not been synchronized. At time t=1, the counter of the third D2D device UE#3 reaches the preset threshold value 10, and therefore, the third D2D device UE#3 sends the proximity signal to the other D2D devices UE#1 and UE#2. After receiving the proximity signal sent by the D2D device UE#3, the counters of the D2D devices UE#1 and UE#2 are incremented by 3 in addition to the original increment. This causes the count value of the D2D device UE#2 to also reach the threshold value. Therefore, the D2D device UE#2 also sends a neighboring signal to the other D2D devices UE#1 and UE#3. After the proximity signal is sent, the count values of the two devices UE#2 and UE#3 will be reset to zero. Observing the phase change at time t=1, it can be seen that the count value of the D2D device UE#1 just increases the two increments generated by UE#2 and UE#3. Furthermore, at this time, the phases of UE#2 and UE#3 have been synchronized.

At time t=2, the counter of the D2D device UE#1 is incremented by one, so that its counter value reaches the threshold value, and therefore, the D2D device UE#1 sends the neighboring signal. The proximity signal sent by the D2D device UE#1 will also be D2D at the same time. The count value of the counters of the devices UE#2 and UE#3 is changed from 1 to 4. Thereafter, the counter of the D2D device UE#1 will reset its value to zero. During the period from time t=3 to time t=7, since no device's count value reaches the threshold, no proximity signal is received. Therefore, the three D2D devices will increase their counters at the originally set rate 1 in each time slot. At time t=8, since the time of the D2D device UE#2 and UE#3 has been synchronized, the proximity signal received by UE#1 is twice the intensity. Therefore, the D2D device UE#1 will increase by two increments at a time, so that the value of the counter of the D2D device UE#1 is as high as the threshold value of other D2D devices. At this time, the three devices UE#1, UE#2, and UE#3 have reached synchronization. After several steps, all D2D devices UE#1, UE#2 and UE#3 with the same proximity signal will reach a state in which the timing of a neighboring signal is exactly aligned. That is to say, the D2D device UE#1 knows the time point when the D2D device UE#2 and UE#3 transmit the proximity signal, and the D2D devices UE#2 and UE#3 also know the time point at which the other D2D device transmits the proximity signal. Therefore, the D2D devices UE#1, UE#2, and UE#3 are synchronized by the alignment of the adjacent signal timings. After the D2D devices UE#1, UE#2 and UE#3 reach synchronization, since the timings of the neighboring signals are aligned, the D2D devices UE#1, UE#2 and UE#3 will eventually send the neighboring signals at the same time.

In some embodiments, after the D2D device reaches synchronization, various communication activities can be performed further between the synchronized D2D devices.

In another exemplary embodiment, the present disclosure provides a keepalive signaling mechanism for a D2D communication system. The aforementioned keep-alive signaling mechanism can be applied to check the status of all D2D devices in the same group, for example, whether a neighboring D2D device exists or whether a wireless connection with a neighboring D2D device exists. Specifically, the aforementioned connection connection signaling mechanism can be applied to check with Whether the neighboring D2D device exists in the same application. In this example, the proximity signal may indicate whether a neighboring D2D device is present, whether a wireless connection with a neighboring D2D device is present, or whether a neighboring D2D device having the same application preference exists. The implementation of the aforementioned connection connection signaling mechanism can detect whether the neighboring device remains alive by skipping some transmission of the adjacent signal. When the neighboring signal broadcasted by the neighboring device can be detected, the neighboring device is determined to be in a connected state; otherwise, the neighboring device is determined to be in an unconnected state (or a dead state). In an embodiment, the proximity signal is transmitted using a periodically skipped transmission mode. In another embodiment, the proximity signal is transmitted using a random skip transmission. In yet another embodiment, the network entity can set how to skip the transmission of the neighboring signals.

In some embodiments, the communication device 110 has a second proximity communication device adjacent thereto, and the communication device, the first proximity communication device, and the second proximity communication device form a D2D group after synchronization is completed by using a fourth proximity signal. And the D2D group further performs the foregoing maintaining connection procedure to check whether the second proximity communication device exists. The D2D group performs the foregoing connection connection procedure by: skipping in a first time period Transmitting a fourth proximity signal, detecting whether the second proximity communication device does not transmit the fourth proximity signal in the first time period, and determining the second proximity communication device according to the determination result of one of the detecting It is connected or unwired.

Figure 5A shows a flow chart of a keep-alive procedure in accordance with an embodiment of the present disclosure. In this embodiment, the hold connection procedure can be applied to each communication device (or D2D device) in the D2D communication system 100 shown in FIG. 1. The keep-alive procedure can include the following steps: skipping once in a first time period The transmission of the fourth proximity signal (step S502) and whether the proximity signal transmitted by any adjacent communication device can be detected in the first time period (step S504). If a neighboring signal transmitted by a neighboring communication device can be detected (YES in step S504), it is determined that the neighboring device is in a wired state (step S506). If the proximity signal sent by a neighboring communication device cannot be detected (NO in step S504), it is determined that the neighboring device is in an unconnected state (step S508).

FIG. 5B is a schematic diagram showing a retention connection mechanism in accordance with an embodiment of the present disclosure. As shown in FIG. 5B, the D2D devices UE#1-UE#4 form a D2D group. In this example, it is assumed that the D2D devices UE#1-UE#4 have used a neighboring signal to achieve synchronization, so at the time period t0, the time points at which these D2D devices transmit the neighboring signals are the same. The D2D device UE#1-UE#4 then performs the aforementioned hold connection procedure after the synchronization is completed, checking whether other D2D devices exist. Specifically, the D2D device UE#1-UE#4 can skip the transmission of the neighboring signal to detect whether the neighboring device remains connected. For example, some broadcast transmissions of neighboring signals may be skipped in order to detect the presence of neighboring devices UE#2-UE#4, wireless connectivity, or preferences for a particular service. In FIG. 5B, since the D2D device UE#4 misses the transmission of all the adjacent signals in the time periods t1, t2, and t3, the D2D device UE#1 can know that the D2D device UE#4 is dead or unconnected. status. Similarly, since the D2D device UE#2 only skips the transmission of the adjacent signal in the time period t2, the D2D device UE#1 can know that the D2D device UE#2 is still in the wired state.

In some embodiments, the D2D group may further execute a triggering process to trigger a designated service by using a fifth neighboring signal, wherein the D2D group may transmit the fifth neighboring signal to the second communication device to trigger The above specified service steps are performed to execute the above trigger procedure. In another embodiment, the D2D device After the synchronization is achieved by using a first neighboring signal, a triggering process is further executed to trigger a specific service, wherein the triggering process may further include the step of transmitting a second neighboring signal that triggers a specific service to other neighboring devices. Figure 6A shows a flow chart of a triggering procedure in accordance with an embodiment of the present disclosure. In this embodiment, the triggering procedure can be applied to each of the communication devices in the D2D communication system 100 shown in FIG. 1. First, the broadcast transmits a first proximity signal to synchronize between different D2D devices executing a first application (step S602). Then, transmitting a second proximity signal to a designated device, triggering a specific service in the first application executed by the designated device (step S604). See Figure 6B. FIG. 6B is a schematic diagram showing a trigger mechanism according to an embodiment of the present disclosure. As shown in FIG. 6B, the D2D devices UE#1-UE#4 form a D2D group. This D2D group provides two services: synchronization and data session. The synchronization between the D2D devices UE#1-UE#4 is implemented by using a first proximity signal Signal_Blue, and the initialization of the data segment is implemented by using a second proximity signal Signal_Red. For example, the first and second proximity signals may be different RACH codes. For example, two different codes (eg, a pair of RACH codes) can be used to transmit proximity signals, where one code can indicate standby and continue to be used as a synchronization and/or continuous program, while another code can trigger other Event (for example: when this boot code is sent, other devices know that a data section will be started). After the D2D device UE#1-UE#4 synchronizes with the first neighboring signal Signal_Blue, if the D2D device UE#1 wants to establish a data segment with the D2D device UE#2, the D2D device UE#1 may transmit the second neighbor. Signal Signal_Red to D2D device UE#2, initializes the data segment service. For example, the D2D device UE#1-UE#4 executing the same specific application may first use the first neighboring signal to achieve synchronization. Then, the D2D device UE#1 can transmit the second proximity signal to the D2D device UE#2, and the data segment service with the UE#2 is initialized in this specific application.

In some embodiments, the manner of setting the command from the network entity to the D2D UE is further provided. The network entity may utilize a radio resource control (RRC) layer or media access control (MAC) layer of signaling, system information block (SIB), and/or primary information block (master) Information block (MIB), or broadcast/multicast service to set up the D2D UE. In most communication systems, the receiver can receive data transmissions sent by unicast, broadcast or multicast. For example, the Multimedia Broadcasting and Multicast Service (MBMS) is a service in which a base station transmits general preference information on a shared channel, so that a device subscribing to the service can access the MBMS channel to obtain a favorite service. For example: daily news service or score game service for baseball games, etc.

In the LTE system, the RRC command controls the operation of a specific UE. Therefore, the network entity (which may be a base station or some nodes in the core network such as an MME, etc.) may initialize the RRC command to set the desired D2D UE. The established threshold can be set through the RRC layer and can be broadcasted in the system information. Therefore, the communication device 110 can obtain the set value of the predetermined threshold value by receiving the system information broadcasted by the base station 212. It can be understood that, although not shown in the figure, the controller module 114 can first receive the system information that is broadcast by the base station 212 and includes the predetermined threshold value through the wireless module 112, and set the predetermined threshold value accordingly.

In another embodiment, the network entity may set some or all of the D2D devices. For example, a network entity can only set D2D devices in the same group. Set, set up D2D devices in several groups or set all D2D devices. The network entity can use the system information message to set the D2D device. For example, some or all of the UEs within the coverage of the signal of the base station 212 can be set by using the MIB or SIB in the LTE system.

When the network entity is not a serving base station (e.g., base station 212), the network entity can dispatch the aforementioned SIB or MIB by requesting a specific base station or a group of base stations. In another embodiment, the network entity may also initiate an MBMS service to set up all D2D devices that subscribe to the broadcast/group dial service.

In some embodiments, the network entity may further configure a third proximity signal to a first group of communication devices and a fourth proximity signal to a second group of communication devices, wherein the first group of communications The device requests a first service and the communication device of the second group to request a second service, and the third proximity signal and the fourth proximity signal are two signals using different random access channel codes. In some embodiments, the network entity may further configure a third proximity signal to a first group of communication devices and a fourth proximity signal to a second group of communication devices, wherein the first group of communications The device requests a first service and a second group of communication devices to request a second service through a second resource, and the first resource and the second resource are different random access channel resources. In some embodiments, a third proximity signal is used for a first group of communication devices and a fourth proximity signal is used for a second group of communication devices, wherein the first group of communication devices request a The first service and the communication device of the second group request a second service, and the third proximity signal and the fourth proximity signal are signals using different random access channel codes. In some embodiments, a third proximity signal is used for a first group of communication devices and a fourth proximity signal. For a second group of communication devices, wherein the first group of communication devices request a first service and a second group of communication devices to request a second service through a first resource through a first resource, and The first resource and the second resource are different random access channel resources.

Therefore, according to the D2D communication device, the system and the D2D communication method thereof, the proximity detection at the application level and the proximity discovery at the physical communication level can be simultaneously realized by transmitting and detecting adjacent signals between the D2D devices, and Synchronization is achieved between D2D devices. Furthermore, the D2D communication device and system and the D2D communication method thereof according to the present disclosure can further promote synchronization between D2D devices, maintain D2D devices in a wired state, or trigger applications between D2D devices, in addition to proximity discovery. The program or transmission can achieve the purpose of D2D communication between D2D devices and can greatly reduce the network resources required.

The above methods can be implemented and stored in a machine readable storage medium such as a magnetic tape, a semiconductor, a magnetic disk, and/or an optical disk (including a Compact Disc Read-Only Memory, digital multi-function only). A machine readable storage medium such as a memory (Digital Versatile Disk Read-Only Memory), etc., and the code is transmitted through a processing unit, a Micro-Control Unit (MCU), or by FIG. When the controller module 114 is loaded and executed, the above D2D communication method can be executed in a D2D system. In addition, the above method can also be applied to any communication device having D2D communication capability supporting wideband code division multiplexing access technology and/or long term evolution technology.

The present invention is disclosed in the above embodiments, but it is merely an example and not to limit the scope of the invention, and anyone skilled in the art can In the spirit and scope of the disclosure, when you can make some changes and refinements. Therefore, the above embodiments are not intended to limit the scope of the present invention, and the scope of the present invention is defined by the scope of the appended claims.

S202, S204, ..., S210‧‧ steps

Claims (34)

A communication device that performs wireless communication with a device-to-device (D2D) of a first proximity communication device, including: a wireless module that performs wireless transmission and reception; a counter that has a count value and Having a threshold value corresponding to one of the counters; and a controller module determining whether to transmit the proximity signal through the wireless module according to the comparison result of the counting value and the threshold value; wherein, when the counting value is When the threshold value is reached, the controller module determines to send a first proximity signal to the first neighboring communication device through the wireless module, and wherein the counter value of the counter is broadcast according to the first proximity communication device. One of the second proximity signals is sent up or down. The communication device of claim 1, wherein the controller module further detects the first proximity signal when the second proximity signal broadcasted by the first proximity communication device is received The communication device is adjacent. The communication device of claim 1, wherein the communication device simultaneously performs a first service with the first proximity communication device, and the counter value of the counter is periodically when no proximity signal has been received yet. And incrementing by a first quantity and the counter value of the counter is incremented by a second quantity when receiving the second neighboring signal broadcasted by the first neighboring communication device. The communication device of claim 1, wherein the controller module resets the counter after transmitting the first proximity signal. The communication device of claim 1, wherein the controller module broadcasts the first proximity signal to the first proximity communication device more periodically or according to the counter value of the counter, and broadcasts the foregoing A proximity signal to the first proximity communication device. The communication device of claim 1, wherein the first proximity signal is a CDMA code or a preamble. The communication device of claim 1, wherein the communication device synchronizes with the first proximity communication device by using a third proximity signal, so that the communication device transmits the third device simultaneously with the first proximity communication device Proximity signal. The communication device of claim 7, wherein the communication device has a second proximity communication device adjacent thereto, and the communication device, the first proximity communication device and the second proximity communication device are utilized by the first Forming a D2D group after the four neighboring signals complete synchronization, and the D2D group further performs a keepalive procedure to check whether the second neighboring communication device exists, wherein the D2D group performs the above-mentioned keep-alive procedure Detecting whether the second proximity communication device does not transmit the fourth proximity signal and detecting the second proximity communication device during the first time period by skipping the transmission of the fourth proximity signal in a first time period As a result of the determination, it is determined that the second proximity communication device is in an alive state or a not alive state. The communication device of claim 1, further comprising a network entity configured to configure the communication device and the first proximity communication device, wherein the controller module further transmits the wireless entity from the network entity Receive one contains The configuration request of the configuration data is applied to the communication device according to the configuration request. The communication device of claim 1, wherein the first proximity signal and the second proximity signal are two signals using different random access channel codes. A device-to-device communication system for performing wireless communication between a device and a device, comprising at least a first communication device and a second communication device, wherein each of the first communication device and the second communication device comprises: a wireless device a module for performing wireless transmission and reception; a counter having a count value and having a threshold corresponding to the counter; and a controller module determining the result based on the comparison between the count value and the threshold value Whether to transmit the proximity signal through the wireless module; wherein the controller module of the first communication device determines that the first communication is transmitted when the count value corresponding to the first communication device reaches the threshold value The wireless module of the device broadcasts a first proximity signal to the second communication device, and wherein the count value corresponding to the first communication device is increased according to a second proximity signal broadcast by the second communication device. Or reduce. The device-to-device communication system of claim 11, wherein the controller module of the first communication device further detects when the second proximity signal broadcasted by the second communication device is received It is detected to be adjacent to the second communication device. For example, the device-to-device communication system described in claim 11 The first communication device and the second communication device simultaneously perform a first service, and the count value corresponding to the first communication device is periodically incremented by a first quantity when no proximity signal has been received yet. The corresponding count value is incremented by a second amount when receiving the second proximity signal broadcasted by the second communication device. The device-to-device communication system of claim 11, wherein the controller module of the first communication device resets the corresponding counter after transmitting the first proximity signal. The device-to-device communication system of claim 11, wherein the controller module of the first communication device broadcasts the first proximity signal to the second communication device more periodically or according to the first And transmitting, by the communication device, the first neighboring signal to the second communication device. The device-to-device communication system of claim 11, wherein the first proximity signal is a CDMA code or a preamble. The device-to-device communication system of claim 11, wherein the first communication device and the second communication device are synchronized by a third proximity signal, such that the first communication device and the second communication device are The third proximity signal is transmitted at the same time. The device-to-device communication system of claim 17, further comprising a third communication device adjacent to one of the first communication devices, and the first, second, and third communication devices are utilized After the fourth neighboring signal completes synchronization, a D2D group is formed, and the D2D group further performs a keep-alive procedure to check whether the third communication device exists, wherein the D2D group Performing, by the group, the maintaining the connection procedure, by: skipping the transmission of the fourth proximity signal in a first time period, and detecting, in the first time period, whether the third communication device does not transmit the fourth proximity The signal, and the determination result according to one of the detections, determines that the third communication device is in a wired state or an unconnected state. The device-to-device communication system of claim 18, wherein the D2D group executes a triggering process, and triggers a specified service by using a fifth proximity signal, wherein the D2D group executes the triggering process Transmitting the fifth proximity signal to the second communication device to trigger the specified service. The device-to-device communication system of claim 11, further comprising a network entity configured to configure the first communication device and the second communication device, wherein the foregoing control of each of the first and second communication devices The device module further receives a configuration request including configuration data from the network entity through the wireless module corresponding thereto, and applies the configuration data to the corresponding first communication device or the foregoing according to the configuration request. Two communication devices. The device-to-device communication system of claim 20, wherein the network entity further configures a third proximity signal to a first group of communication devices and a fourth proximity signal to a second group. The communication device, wherein the communication device of the first group requests a first service and the communication device of the second group to request a second service, and the third proximity signal and the fourth proximity signal are different in use. Two signals of random access channel code. The device-to-device communication system of claim 20, wherein the network entity further configures a third proximity signal to a first group. And the communication device configured to send a fourth proximity signal to a second group, wherein the communication device of the first group requests a first service and a communication device of the second group through a first resource The second resource requests a second service, and the first resource and the second resource are different random access channel resources. The device-to-device communication system according to claim 11, wherein the network entity further manages a correspondence between different services and random access channel codes or different services and corresponding random access channel resources. The coding of the correspondence relationship and the code-interest mapping information. The device-to-device communication system of claim 11, wherein a third proximity signal is used for a first group of communication devices and a fourth proximity signal is used for a second group of communication devices. The communication device of the first group requests a first service and the communication device of the second group to request a second service, and the third proximity signal and the fourth proximity signal are different random accesses. Two signals of the channel code. The device-to-device communication system of claim 11, wherein a third proximity signal is used for a first group of communication devices and a fourth proximity signal is used for a second group of communication devices. The communication device of the first group requests a first service and the communication device of the second group to request a second service through a first resource, and the first resource and the second resource are Is a different random access channel resource. A device-to-device wireless communication method, applicable to a device-to-device communication system, comprising at least a first communication device and a second communication device, The first communication device determines whether to broadcast a first proximity signal according to a comparison result of a counter corresponding to one of the first communication devices and a threshold value corresponding to one of the counters. The second communication device; and when the count value corresponding to the first communication device reaches the threshold value, the first communication device determines to broadcast the first proximity signal to the second communication device, wherein the first communication The counting value corresponding to the device is increased or decreased according to one of the second proximity signals broadcasted by the second communication device. The device-to-device wireless communication method of claim 26, further comprising: when receiving the second proximity signal broadcasted by the second communication device, the first communication device detects the The second communication device is adjacent. The device-to-device wireless communication method of claim 26, further comprising: periodically incrementing the count value corresponding to the first communication device by a first amount when no proximity signal has been received; And receiving the count value corresponding to the first communication device by a second amount when receiving the second proximity signal broadcasted by the second communication device. The device-to-device wireless communication method as described in claim 26, further comprising: After the first proximity signal is sent by the broadcast, the first communication device resets the corresponding counter. The device-to-device wireless communication method of claim 29, further comprising: the first communication device periodically broadcasting the first proximity signal to the second communication device or according to the first communication device The counting value broadcasts the first proximity signal to the second communication device. The device-to-device wireless communication method of claim 30, wherein the first communication device and the second communication device are synchronized by a third proximity signal, such that the first communication device and the second communication are The device simultaneously transmits the third proximity signal. The device-to-device wireless communication method of claim 31, wherein the device-to-device communication system further comprises a third communication device adjacent to one of the first communication devices, wherein the first, second, and third The communication device is configured to form a D2D group after the synchronization is completed by using a fourth proximity signal, and the D2D group further performs a hold connection procedure to check whether the third communication device exists, wherein the remaining connection program is further The method includes the following steps: in a first time period, the first communication device skips transmission of the fourth proximity signal; in the first time period, the first communication device detects whether the third communication device is not transmitted And the first communication device determines that the third communication device is in a wired state or an unconnected state according to the determination result of the one of the detecting. Device-to-device wireless communication party as described in claim 32 The method, wherein the D2D group further performs a triggering process, and triggers a specified service by using a fifth neighboring signal, wherein the triggering process further comprises the following steps: the first communications device transmits the fifth neighboring signal to the second A communication device to trigger the specified service described above. The device-to-device wireless communication method of claim 26, wherein the device-to-device communication system further comprises a network entity, the first communication device and the second communication device are configured, and the method further comprises the following Step: the network entity transmits a configuration request including configuration data to the first communication device; and when receiving the configuration request from the network entity, the first communication device performs the first communication according to the configuration request The above configuration data is applied to the device.