CN107295567B - Wireless resource conflict detection method based on frame structure - Google Patents
Wireless resource conflict detection method based on frame structure Download PDFInfo
- Publication number
- CN107295567B CN107295567B CN201710602481.7A CN201710602481A CN107295567B CN 107295567 B CN107295567 B CN 107295567B CN 201710602481 A CN201710602481 A CN 201710602481A CN 107295567 B CN107295567 B CN 107295567B
- Authority
- CN
- China
- Prior art keywords
- collision detection
- priority
- collision
- data
- data transmission
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W28/00—Network traffic management; Network resource management
- H04W28/02—Traffic management, e.g. flow control or congestion control
- H04W28/0294—Traffic management, e.g. flow control or congestion control forcing collision
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W74/00—Wireless channel access, e.g. scheduled or random access
- H04W74/08—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access]
- H04W74/0808—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using carrier sensing, e.g. as in CSMA
- H04W74/0825—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using carrier sensing, e.g. as in CSMA carrier sensing with collision detection
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W74/00—Wireless channel access, e.g. scheduled or random access
- H04W74/08—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access]
- H04W74/0833—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using a random access procedure
- H04W74/0841—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using a random access procedure with collision treatment
- H04W74/085—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using a random access procedure with collision treatment collision avoidance
Abstract
The invention relates to a frame structure-based infinite resource conflict detection method, and belongs to the field of wireless communication. The method comprises the following steps: s1: dividing a wireless frame into a conflict detection area and a data transmission area; s2: dividing conflict detection codes carried by the conflict detection time slot into high-priority conflict detection codes and low-priority conflict detection codes; sending a collision detection code on a collision detection time slot; s3: the equipment detects all collision detection codes in the collision detection time slot, evaluates the collision severity existing in the data transmission area by detecting the number of the collision detection codes and determines the back-off time of the equipment according to the collision severity; if no other device is found to transmit the collision detection code, the device uses the radio resources of the data transmission region. The invention solves the problem of competitive use of transmission resources under the condition of frame synchronization; in addition, the collision detection codes are divided into different priorities, so that the method is suitable for scenes in which transmission resources are used in competition with different priorities.
Description
Technical Field
The invention belongs to the field of wireless communication, and relates to a wireless resource conflict detection method based on a frame structure.
Background
By adopting a distributed control method, each node attached to the bus obtains the use right of the bus in a competitive mode. Only the node that obtains the usage rights can send a frame of information to the bus that will be perceived by all nodes attached to the bus. The method comprises the following three points: firstly, the method comprises the following steps: carrier sense, before sending information frame, sending node must sense whether the media is in idle state; secondly, the method comprises the following steps: multiple access, which has two meanings, not only means that a plurality of nodes can access the medium at the same time, but also means that the information frame sent by one node can be received by a plurality of nodes; thirdly, the method comprises the following steps: collision detection, in which a sending node must monitor the medium while sending an information frame, and determine whether a collision occurs (whether other nodes are sending information frames at the same time). Two methods are available, the Carrier sense multiple Access/Collision detection mechanism (CSMA/CD, Carrier sense multiple Access/Collision detection) and the Carrier sense multiple Access/Collision avoidance (CSMA/CA).
CSMA/CD approach, i.e. carrier sense multiple access/collision detection mechanism. When a plurality of network devices on the wired Ethernet need to transmit data simultaneously, the protocol can be used for detecting the conflict on the network and processing the conflict correspondingly. The working principle can be summarized as listening before speaking and listening while speaking; stopping speaking immediately once the conflict occurs; wait for opportunity and then speak again. However, it is not suitable for a wireless local area network in which the transmission distance of radio waves is limited and not all nodes can monitor signals; moreover, because the wireless network card operates in half-duplex mode, the device cannot transmit data signals while receiving data signals. On the other hand, the wireless bandwidth is not high, and data is retransmitted in the event of a collision, and the throughput is reduced accordingly.
The CSMA/CD is modified by a new protocol CSMA/CA, and the working principle of the CSMA/CA is as follows:
(1) firstly, whether a channel is used by a station (called STA for short) is detected, if the channel is detected to be idle, data is sent out after waiting for a distributed coordination function interframe space (called DIFS for short).
(2) If the destination STA receives the frame correctly, after a short inter-frame space (SIFS) time, the destination STA sends an acknowledgement frame ACK to the source STA.
(3) The source STA receives the ACK frame, determines that the data transmission is correct, and after the DIFS time interval elapses, an idle time, called a contention window, may occur, indicating that there may be a contention for the channel by the STAs.
If the channel is found to be occupied while sensing the channel, the STA freezes the backoff timer using the backoff algorithm of the CSMA/CA protocol. The backoff timer counts down whenever the channel is idle. When the backoff timer decreases to zero, the STA sends a data frame and waits for an acknowledgement. If an ACK frame is not received after the data frame is transmitted, the frame must be retransmitted.
In the current CSMA/CD or CSMA/CA, there is a problem that when a plurality of stations request to transmit data, collision occurs because all stations can only back off according to the same mechanism and participate in the next round of collision competition again without knowing the severity of collision. This approach has significant drawbacks in practical deployment applications:
firstly, the method comprises the following steps: when a plurality of stations request to send data at the same time, collision occurs, but each station only knows that other stations also request to send data, but does not know how many stations request to send data, so that the severity of the collision cannot be evaluated.
Secondly, the method comprises the following steps: when the station sends data and generates collision, the collision degree cannot be objectively evaluated, so that no method is available for giving reasonable back-off time, and only one back-off time can be randomly selected within one time.
Thirdly, the method comprises the following steps: there are different priorities for stations to send data, but there is no way to increase the probability of high priority sending data according to current implementations. That is, in practical applications, for example, signaling may be set to a high priority and there may be a priority to transmit in collision contention.
So the current CSMA/CD or CSMA/CA has certain defects in practical use.
Disclosure of Invention
In view of the above, the present invention provides a method for contention based use of radio resources in a wireless communication system, which is based on the principle that radio resources are managed and used in a radio frame manner, and the radio frame is first divided into a collision detection area and a data transmission area, wherein one collision detection area and one data transmission area constitute one transmission unit. The conflict detection area is used for coordinating a plurality of devices to compete for using the data transmission area and is composed of a plurality of conflict detection time slots. The data transmission area is used for the equipment to transmit data with high priority or low priority, and the data transmission area can be composed of a plurality of data transmission frames.
In order to achieve the purpose, the invention provides the following technical scheme:
a wireless resource conflict detection method based on a frame structure comprises the following steps:
s1: dividing a wireless frame into a collision detection area and a data transmission area, wherein one collision detection area and one data transmission area form a transmission unit; the collision detection area is composed of a plurality of collision detection time slots and is used for coordinating a plurality of devices to compete for using the data transmission area, and the data transmission area is composed of a plurality of data transmission frames and is used for the devices to transmit data with high priority or low priority;
s2: dividing conflict detection codes carried by the conflict detection time slot into high-priority conflict detection codes and low-priority conflict detection codes; randomly selecting one from the high-priority collision detection codes if the device transmits high-priority data, and randomly selecting one from the low-priority collision detection codes if the device transmits low-priority data; sending a collision detection code on a collision detection time slot;
s3: the equipment detects all collision detection codes in the collision detection time slot, evaluates the collision severity existing in the data transmission area by detecting the number of the collision detection codes and determines the back-off time of the equipment according to the collision severity; if no other device is found to transmit the collision detection code, the device uses the radio resources of the data transmission region.
Further, in the step S3:
if the equipment does not find the collision detection code sent by other equipment, determining that the equipment has the use permission of the data transmission area;
if the device finds the collision detection codes sent by other devices and the priority of all the collision detection codes is lower than that of the device, the device has the use right of the data transmission area;
if the device finds that the priority of the collision detection code sent by other devices is the same as or higher than that of the device, the device selects a reasonable back-off time to participate in the competition of the transmission unit, namely the wireless resource, again.
Further, in the step S3:
the equipment detects t high-priority conflict detection codes, wherein t is more than or equal to 0, and s low-priority conflict detection codes, wherein s is more than or equal to 0; when the device detects that t + s is not equal to 0; if the equipment sends high-priority data, the equipment randomly selects a transmission unit to compete for using the wireless resources in the subsequent transmission units 0-t; if the equipment sends low-priority data, the equipment randomly selects one transmission unit from the subsequent transmission units t-t + s to participate in the competition of wireless resources;
further, in a collision scenario, the device selects to use the subsequent transmission unit number to start from 0, and the transmission unit with backoff 0 is the own transmission unit in collision;
the equipment waits for the arrival of the randomly selected transmission unit time, and when the transmission unit time arrives, the equipment reselects the collision detection code and participates in the process of competing for using the data transmission area again.
The invention has the beneficial effects that:
(1) the invention solves the problem of transmission resource competition use under the frame synchronization condition. In the existing frame synchronization mode, transmission resources are uniformly allocated and used, and there is no competitive use scenario, but with the increase of services and scenarios, although different devices have the same frame synchronization, there is also a competitive use transmission resource scenario.
(2) The invention uses the mode of orthogonal collision detection codes, obtains the severity of the collision when the equipment detects the collision, and determines the quantity of the equipment which uses the same transmission resource in a competition manner.
(3) The invention divides the conflict detection code into different priorities, and can adapt to the scene of competing using transmission resources with different priorities.
Drawings
In order to make the object, technical scheme and beneficial effect of the invention more clear, the invention provides the following drawings for explanation:
FIG. 1 is a diagram illustrating a frame structure based radio resource collision detection;
FIG. 2 is a diagram of a process for coordinating radio resources based on a frame structure;
fig. 3 is a back-off mechanism in a wireless transmission collision;
FIG. 4 is a conflict resolution mechanism in the conventional CP mode;
FIG. 5 is a conflict resolution mechanism in extended CP mode;
fig. 6 is a collision resolution mechanism in LTE frame mode;
fig. 7 is a collision backoff mechanism in LTE frame mode;
figure 8 is a schematic diagram of a scenario in which a small cell and a mobile terminal compete for use of multiple transmission units;
fig. 9 shows a multi-channel collision avoidance mechanism in LTE frame mode.
Detailed Description
Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
As shown in fig. 1, the present invention manages and uses radio resources in a radio frame manner, and first divides the radio frame into a collision detection area and a data transmission area, where one collision detection area and one data transmission area constitute one transmission unit. The conflict detection area is used for coordinating a plurality of devices to compete for using the data transmission area and is composed of a plurality of conflict detection time slots. The data transmission area is used for the equipment to transmit data with high priority or low priority, and the data transmission area can be composed of a plurality of data transmission frames.
The collision detection time slot in each collision detection zone may carry multiple collision detection codes with orthogonal properties, the collision detection codes are divided into two groups, a high priority collision detection code and a low priority collision detection code, one of the high priority collision detection codes is randomly selected if the device sends high priority data, and one of the low priority collision detection codes is randomly selected if the device sends low priority data, and the collision detection codes are sent on the collision detection time slot.
When the device performs collision detection, all collision detection codes in a collision detection time slot are detected firstly, the collision severity existing in a data transmission area is evaluated by detecting the number of the collision detection codes, and the back-off time of the device is determined according to the evaluation. If no other device is found to transmit the collision detection code, the device may use the radio resources of the data transmission region.
The following describes the radio resource coordination procedure based on the frame structure provided by the present invention, as shown in fig. 2.
Step 1: all the devices use the same method to divide the collision detection codes into two groups, namely high-priority and low-priority collision detection codes. As shown in step 1 of fig. 2.
Step 2: if the device requests to send high priority data, a code is randomly selected from the high priority collision detection codes, and if the device requests to send low priority data, a code is randomly selected from the low priority collision detection codes and sent out on a subsequent collision detection time slot. As shown in steps 2, 3, 4 and 5 in fig. 2.
And step 3: after the device randomly selects a collision detection time slot in the subsequent collision detection time slots, the device stops sending the collision detection code on the collision detection time slot and detects the collision detection code sent by other devices on the collision detection time slot. As shown in step 6 of figure 2.
And 4, step 4: and if the device does not find the collision detection code sent by other devices in the step 3, determining that the device has the use right of the data transmission area. As shown in steps 7 and 8 in fig. 2.
And 5: if in step 3, the device finds the collision detection codes sent by other devices and all the collision detection code priorities are lower than the collision detection code priority of the device, the device has the right of use of the data transmission area.
Step 6: if in step 3, the device finds that the priority of the collision detection code of the other device is the same as or higher than that of the device, the device selects a reasonable back-off time to participate in the contention of the transmission unit, i.e., the wireless resource, again. As shown in steps 9, 10 and 11 of fig. 2.
The backoff procedure for the frame structure based wireless resource collision coordination provided by the present invention is described in detail below, as shown in fig. 3.
Step 1: the device randomly selects a collision detection time slot in the upcoming collision detection zone, i.e. randomly selects a collision detection time slot in the collision detection zones 1-M as in fig. 1. As shown in step 1 of fig. 3.
Step 2: the device will detect all collision detection codes in the randomly selected collision detection time slot, assuming that the device detects t (t is greater than or equal to 0) high priority collision detection codes and s (s is greater than or equal to 0) low priority collision detection codes. If the device does not find the high priority conflict detection code and the low priority conflict detection code, the device has the use authority of the wireless resource in the data transmission area. As shown in steps 2, 3, 4 and 5 in fig. 3.
And step 3: if in step 2, the device detects that t + s is not equal to 0, and if the device sends high-priority data, the device randomly selects one transmission unit from the subsequent transmission units 0 to t to compete for using the wireless resource, wherein the randomly selected subsequent transmission unit is 0, which means that the conflicting transmission unit is selected for data transmission. If the equipment sends low-priority data, the equipment randomly selects one transmission unit from the subsequent transmission units t-t + s to participate in the competition of wireless resources. As shown in steps 6, 7 and 8 in fig. 3.
And 4, step 4: the device waits for a randomly selected transmission unit time to arrive. When the transmission unit time arrives, the equipment reselects the collision detection code and participates in the process of competing for using the data transmission area again. As shown in step 9 of fig. 3.
Two application scenarios are illustrated below, namely, a scenario in which an LTE small cell contends for using a wireless resource, and a scenario in which an LTE mobile terminal performs direct communication.
Specific example 1:
in the future, the deployment and application of LTE small cells, plug and play, is a development direction, and can be deployed like WiFi hotspots, but the plug and play function of small cells will bring a great impact on the planning and use of wireless resources, mainly because there is no way to coordinate the use of wireless resources in time between different small cells, so that the competition of small cells for using wireless resources will be unavoidable. The present invention provides a method of resolving such conflicts.
To clearly illustrate the details of the use of the present invention, the following description will be made from two perspectives, first of all, a method in which a plurality of LTE terminals contend to use the same transmission unit, and then a method in which a plurality of LTE terminals contend to use a plurality of transmission units.
Before data transmission is performed between a plurality of small cells and an LTE terminal, the same transmission unit needs to be used in a competition mode, and before a specific operation mode is described, a basic concept is introduced:
firstly, the method comprises the following steps: time slot resource division: continuing with the current LTE frame structure, if it is in normal CP mode, a subframe is divided into 14 Orthogonal Frequency Division Multiplexing (OFDM) symbols, where the first 7 OFDM symbols are used for collision detection area and each symbol is defined as a collision detection slot, as shown in fig. 4. In case of the extended CP mode, one subframe has 12 OFDM symbols, wherein the first 3 OFDM symbols are defined as a collision detection area, as shown in fig. 5. In practical use, the number of collision detection slots (i.e., the number of OFDM slots in this embodiment) may be different according to different systems. For convenience of explanation, in this embodiment example, the normal CP mode, i.e., 7 collision detection slots (7 OFDM time) will be used to explain the specific implementation of the present invention.
Secondly, the method comprises the following steps: definition of transmission unit: according to the requirements of the present invention, the transmission unit is composed of a collision detection area and a data transmission area, and in the present embodiment, it is assumed that the data transmission area is composed of a transmission data area 1 and a transmission data area 2, and the transmission data area may be 1 or more subframe radio resources. For convenience of explanation, the transmission data region 2 is composed of two subframes of 1ms length.
Thirdly, the method comprises the following steps: priority of transmission data: data transmitted in the data transmission area is divided into two types, signaling data and service data. The signaling data is defined as high priority data in the invention, and the service data is defined as low priority data in the invention.
Fourthly: collision detection code: in this embodiment, the collision detection code uses a ZC sequence, and different ZC sequence codes in the ZC sequence are orthogonal to each other.
The following describes data transmission between the small cell and the mobile terminal in detail, and mainly describes an operation flow for coordinating conflicts and using transmission resources. As shown in particular in fig. 6.
Step 1: after the small cell base station is powered on, a nearby macro base station is searched first, and if the macro base station is not received, the nearby small cell base station is searched continuously, and the purpose of the process is to ensure that all small cells in one area keep a synchronous state, namely, have frequency and frame timing synchronization. As in step 1 of fig. 6.
Step 2: when the base station of the small cell sends downlink data to the mobile terminal, or when the small cell receives a request of the mobile terminal to send uplink data, that is, the data transmission between the small cell and the mobile terminal needs to occupy wireless resources. As shown in steps 2 and 3 in fig. 6.
And step 3: the small cell base station first determines the type of data to be transmitted, and if the data is signaling data, the data is defined as high priority data, and if the data is traffic data, the data is defined as low priority data. If the data is high-priority data, an orthogonal collision detection code with high priority is randomly selected, and if the data is low-priority data, an orthogonal collision detection code with low priority is randomly selected. As shown in steps 4, 5 and 6 in fig. 6.
And 4, step 4: the small cell will wait for the next transmission unit time, and the specific calculation is SFN% T _ Schedule ═ T _ Offset, where SFN represents that all small cells keep the same system frame number (in units of radio frames), and T _ Schedule represents the length of the transmission unit, i.e. how many radio frames. T _ Offset represents an Offset amount. T _ Schedule and T _ Offset are preset, and the same parameters are used for all small cells, and in this embodiment, T _ Schedule is 3 and T _ Offset is 0. As shown in step 7 of fig. 6.
And 5: when a transmission unit arrives, the small cell sends orthogonal collision detection codes on collision detection time slots of the transmission unit, except for collision detection time slots needing to be detected, the small cell needs to send each of the remaining collision detection time slots of the transmission unit. As shown in step 8 of fig. 6.
Step 6: the small cell randomly selects one collision detection time slot among all collision detection time slots of the transmission unit. And detecting whether other small cells need to transmit data, if the orthogonal collision detection codes exist, indicating that other small cells also request to use the transmission unit, otherwise, indicating that no other small cells request to use the transmission unit. As shown in step 9 of fig. 6.
And 7: if the small cell detects the orthogonal collision detection code in the collision detection time slot, the small cell will start the collision back-off mechanism in the present invention, otherwise, it indicates that the transmission unit can be used for data transmission between the small cell and the mobile terminal. As shown in step 10 of fig. 6.
The backoff mechanism when the LTE terminal requests to use the transmission resource conflict is described in detail below. As shown in particular in fig. 7.
Step 1: the small cell randomly selects a collision detection time slot, and stops transmitting the orthogonal collision detection code of the small cell in the collision detection time slot. As in step 1 of fig. 7.
Step 2: the small cell receives the data on the selected collision detection time slot and detects all orthogonal collision detection codes. It is assumed that there are t orthogonal collision detection codes for detecting high priority and s orthogonal collision detection codes for detecting low priority. As shown in step 2 of fig. 7.
And step 3: and detecting t + s orthogonal collision detection codes, and if t + s is 0, indicating that no other small cell competes to use the transmission unit, wherein the small cell can use the data transmission cell resource on the transmission unit. As shown in steps 3 and 4 in fig. 7.
And 4, step 4: if t + s is not equal to 0, it indicates that other small cells are also competing for using the data transmission cell resource of the transmission unit, and if signaling data is sent between the small cell and the mobile terminal, the small cell randomly selects one transmission unit from [1, t ] (representing between 1 and t, including 1 and t) transmission units, and participates in contention of the transmission resource again in the collision on the transmission unit. If traffic data is transmitted between the small cell and the mobile terminal, the small cell randomly selects one transmission unit among [ (t +1), (t + s) ] (indicating that t +1 and t + s are included) transmission units, and the transmission unit participates in contention of transmission resources at the time of collision again.
As shown in steps 5, 6 and 7 in fig. 7.
And 5: after the transmission unit is randomly selected, the small cell reselects the corresponding orthogonal collision detection code, waits for the arrival of the selected transmission unit, and then participates in the collision detection of the transmission unit again to complete the process of competing for the transmission resource. As shown in steps 8 and 9 in fig. 7.
In the above, a scenario that one transmission unit is used by a plurality of small cells and terminals in a competition manner is given, and in practical application, the small cells and the mobile terminals can use the transmission units provided by different frequency points in a competition manner. The following describes a method for solving the problem that a plurality of small cells and mobile terminals compete to use a plurality of transmission units by using the invention.
Multiple small cells and mobile terminals compete to use multiple transmission unit scenarios, as shown in particular in figure 8. It is assumed that K transmission units may be used between the small cell and the mobile terminal. Each channel is independent, the transmission unit of each channel starts from the position of SFN% T _ Schedule ═ T _ Offset, and each transmission unit has a collision detection area and a data transmission area.
The following describes a processing flow when multiple small cells and LTE terminals request data transmission using multiple sets of transmission resources and collide with each other. As shown in particular in fig. 9.
Step 1: the small cell first determines the transmission resources that can be used in the region, i.e. determines the available transmission channels, assuming that there are K independent transmission channels. As in step 1 of fig. 9.
Step 2: the small cell that needs to transmit or receive data randomly selects a channel from channel numbers 1 to k, assuming that the randomly selected channel number is z, where z belongs to an integer between 1 and k (which may include 1 and k). As in step 2 of fig. 9. The small cell first contends for use of the transmission unit on channel k.
And step 3: the small cells compete for the use of the transmission unit resources on channel k in such a way that a plurality of small cells and the mobile terminal use the transmission resources in a conflicting manner. As in step 3 of fig. 9.
Specific example 2:
in order to better illustrate the practical use of the invention, reference will be made to the following. In an environment without any coverage of a base station, the LTE terminals need to communicate with each other, and particularly in an emergency or disaster relief scene, since the LTE base station cannot be used, it is necessary to support communication between the LTE terminals. In the same area, there may be many LTE terminals that need to communicate with each other, but there is no way to coordinate and use radio resources between them, and a collision and contention method needs to be adopted. The scenario is a device-to-device (D2D for short), so the present invention can also be applied to the contention usage process of D2D transmission resources.
In the LTE system D2D, there are two ways to use radio resources, one is to determine the radio resources of the D2D terminal by base station scheduling, that is, the base station schedules the time-frequency resources used by the D2D terminal for transmission. Alternatively, a set of radio resources may be configured by the network or may be defaulted by the terminal, and then the D2D terminal randomly selects a set of radio resources to use. In the second case, since no base station performs radio resource coordination between the D2D terminals, there is a case where the D2D terminals contend for use of radio resources. Under the direct connection scene of the D2D terminal, the invention can well solve the conflict generated by wireless resources when no base station is scheduled.
A specific method for solving the direct communication of the D2D terminal is as follows, in conjunction with the description in the above specific embodiment 1.
Step 1: the D2D terminal is powered on, firstly searches for a base station signal, and if the base station signal is not searched, searches for a synchronization signal sent by a nearby D2D terminal, so as to ensure that the D2D terminal in communication refers to the same LTE radio frame time slot and the same system frame number.
Step 2: according to the definition of the current 3GPP standard, the D2D terminal directly uses the radio resources from the system message broadcast, the connection mode configuration, and the terminal default configuration. Wherein, the system message broadcast and the connection mode configuration must be that the terminal is in the coverage area of the base station signal, the network can configure the wireless resource to let the requesting D2D terminal randomly select to use. If D2D is in the no base station coverage area, the D2D terminal can only randomly select the default radio resource usage.
And step 3: if the D2D terminal needs to transmit signaling data, the D2D terminal randomly selects one from the high priority orthogonal collision detection codes, and if the D2D terminal transmits traffic data, the D2D terminal randomly selects one from the low priority orthogonal collision detection codes.
And 4, step 4: the D2D terminal randomly selects a set of radio resources to use. And determines a transmission unit for collision detection according to SFN% T _ Schedule ═ T _ Offset.
And 5: the D2D terminal transmits the selected orthogonal collision detection codes on the collision detection slots in the collision detection zone of the transmission unit, and when a randomly selected one of the collision detection slots arrives, the D2D stops transmitting its own collision detection code while detecting whether the other D2D terminals have transmitted collision detection codes.
Step 6: if the D2D terminal detects the collision detection code sent by other D2D terminals on the collision detection slot, the D2D terminal activates the back-off mechanism in the present patent for processing.
And 7: if the D2D terminal does not detect the collision detection code transmitted by other D2D terminals on the collision detection slot, then the D2D terminal has the right to transmit data on the transmission unit.
Finally, it is noted that the above-mentioned preferred embodiments illustrate rather than limit the invention, and that, although the invention has been described in detail with reference to the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the invention as defined by the appended claims.
Claims (1)
1. A method for detecting wireless resource conflict based on frame structure is characterized in that: the method comprises the following steps:
s1: all code words of all the collision detection codes have orthogonality; dividing a wireless frame into a collision detection area and a data transmission area, wherein one collision detection area and one data transmission area form a transmission unit; the collision detection area is composed of a plurality of collision detection time slots and is used for coordinating a plurality of devices to compete for using the data transmission area, and the data transmission area is composed of a plurality of data transmission frames and is used for the devices to transmit data with high priority or low priority;
s2: dividing conflict detection codes carried by the conflict detection time slot into high-priority conflict detection codes and low-priority conflict detection codes; randomly selecting one from the high-priority collision detection codes if the device transmits high-priority data, and randomly selecting one from the low-priority collision detection codes if the device transmits low-priority data; sending a collision detection code on a collision detection time slot;
s3: the equipment detects all collision detection codes in the collision detection time slot, evaluates the collision severity existing in the data transmission area by detecting the number of the collision detection codes and determines the back-off time of the equipment according to the collision severity; if no other device sends the collision detection code, the device uses the wireless resource of the data transmission area;
in the step S3:
if the equipment does not find the collision detection code sent by other equipment, determining that the equipment has the use permission of the data transmission area;
if the device finds the collision detection codes sent by other devices and the priority of all the collision detection codes is lower than that of the device, the device has the use right of the data transmission area;
if the device finds that the priority of the collision detection code sent by other devices is the same as or higher than that of the device, the device selects a reasonable back-off time and participates in the competition of the transmission unit, namely the wireless resource, again;
in the step S3:
the equipment detects t high-priority conflict detection codes, wherein t is more than or equal to 0, and s low-priority conflict detection codes, wherein s is more than or equal to 0; when the device detects that t + s is not equal to 0; if the equipment sends high-priority data, the equipment randomly selects one transmission unit to compete for using the wireless resources in the subsequent transmission units 0-t, wherein the randomly selected subsequent transmission unit is 0, which means that the conflict transmission unit is selected to carry out data transmission; if the equipment sends low-priority data, the equipment randomly selects one transmission unit from the subsequent transmission units t-t + s to participate in the competition of wireless resources;
the equipment waits for the arrival of the randomly selected transmission unit time, and when the transmission unit time arrives, the equipment reselects the collision detection code and participates in the process of competing for using the data transmission area again.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710602481.7A CN107295567B (en) | 2017-07-21 | 2017-07-21 | Wireless resource conflict detection method based on frame structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710602481.7A CN107295567B (en) | 2017-07-21 | 2017-07-21 | Wireless resource conflict detection method based on frame structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107295567A CN107295567A (en) | 2017-10-24 |
| CN107295567B true CN107295567B (en) | 2020-04-07 |
Family
ID=60102069
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710602481.7A Active CN107295567B (en) | 2017-07-21 | 2017-07-21 | Wireless resource conflict detection method based on frame structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107295567B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109982443A (en) * | 2017-12-28 | 2019-07-05 | 中国移动通信集团湖北有限公司 | Network conflict decomposition method, calculates equipment and storage medium at device |
| CN111756508B (en) * | 2019-03-29 | 2023-04-18 | 华为技术有限公司 | Communication method and device |
| CN113115432B (en) * | 2021-04-15 | 2023-12-08 | 上海金卓科技有限公司 | Wireless communication method, device, equipment and storage medium |
| CN113438691B (en) * | 2021-05-27 | 2024-01-05 | 翱捷科技股份有限公司 | TAS frame processing method and device |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103152765A (en) * | 2005-01-14 | 2013-06-12 | 艾利森电话股份有限公司 | Uplink congestion detection and control between nodes in radio access network |
| CN106533833A (en) * | 2016-11-24 | 2017-03-22 | 重庆邮电大学 | Method for reducing conflict of carrier interception multipath accessing resources |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10182456B2 (en) * | 2015-10-15 | 2019-01-15 | Qualcomm Incorporated | Collision detection in a shared radio frequency spectrum band |
-
2017
- 2017-07-21 CN CN201710602481.7A patent/CN107295567B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103152765A (en) * | 2005-01-14 | 2013-06-12 | 艾利森电话股份有限公司 | Uplink congestion detection and control between nodes in radio access network |
| CN106533833A (en) * | 2016-11-24 | 2017-03-22 | 重庆邮电大学 | Method for reducing conflict of carrier interception multipath accessing resources |
Non-Patent Citations (2)
| Title |
|---|
| 基于优先级调度网络冲突避免模型仿真;周艳丽;《科技通报》;20150630;全文 * |
| 认知网络中基于数据冲突的帧结构优化;姬国庆等;《电路与系统学报》;20130228;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107295567A (en) | 2017-10-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10609712B2 (en) | Communications system, infrastructure equipment, communications devices and method | |
| CN108353398B (en) | Uplink control signaling over a shared communication medium | |
| JP6617141B2 (en) | Method and apparatus for transmitting and receiving signals using unlicensed carriers | |
| EP3016313B1 (en) | Contention based uplink orthogonal frequency-division multiple access | |
| US20180352573A1 (en) | Method and device for determining lbt mode, and method for implementing lbt mode switch | |
| CN109618415B (en) | D2D communication method and device | |
| US10645692B2 (en) | Method and device for indicating uplink subframes on unlicensed frequency spectrum | |
| EP3100545B1 (en) | Inter-group control of semi-persistent channel occupation for device-to-device (d2d) wireless communications | |
| JP7041248B2 (en) | Controlling autonomous UL transmission when coexisting with a scheduled UE | |
| CN107295567B (en) | Wireless resource conflict detection method based on frame structure | |
| CN105230104B (en) | Channel resource allocation method and communication equipment | |
| EP3304992A1 (en) | Transmission of prioritized messages | |
| US10609664B2 (en) | Techniques and apparatuses for frequency division multiplexing (FDM) based medium access on shared spectrum | |
| KR20150128268A (en) | Method and apparatus for distributed scheduling for device to device communications | |
| CN109156000B (en) | System and method for configurable frame structure | |
| CN107211459B (en) | Access point AP, station STA, communication system and data transmission method | |
| CN110915279A (en) | Method for operating a network infrastructure network element, method for operating a road network element, road network element | |
| CN110856271A (en) | Device-to-device terminal resource allocation method and device | |
| KR102049047B1 (en) | Method of data transmitting and receiving in the talk-around direct communication network | |
| WO2019169538A1 (en) | Synchronization method and device based on unlicensed spectrum | |
| KR20160107976A (en) | Data Frame Structure and Operation Method for Sharing a Spectrum asynchronous Cells in Wireless Communication System | |
| EP3673698B1 (en) | Methods and nodes for communication on multiple channels | |
| US20240064783A1 (en) | Sidelink communication method and apparatus | |
| CN111699747A (en) | Random access method and device thereof | |
| US20230217493A1 (en) | Systems and techniques for sidelink communication |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |