阅读说明：本技术 一种tdma无线自组网时钟同步搜索的方法 (Method for synchronous searching of TDMA wireless ad hoc network clock ) 是由 宋飞浩 于 2019-09-04 设计创作，主要内容包括：本发明公开了一种TDMA无线自组网时钟同步搜索的方法。它包括以下步骤：移动台在开机后,先在无线频点f1接收一个超帧以上时间,接着再在无线频点f2接收一个超帧以上时间,如果在上述期间没有接收到任何时标信令,则认为当前没有主钟移动台,接着在之后的一个超帧内随机挑选一个复帧,并在挑选的复帧内随机选择一个时隙并以该时隙对应的无线频点发送一个时隙的时标信令,随后在下一个复帧的相同时隙位置以另一个无线频点发送一个时隙的时标信令,如果该移动台在当前的超帧期间内接收到其他移动台发送的时标信令则参与竞选主钟移动台。本发明缩短了同步时钟的刷新周期和同步时钟的发射持续时间。(The invention discloses a method for searching clock synchronization of a TDMA wireless ad hoc network. It comprises the following steps: after the mobile station is started, firstly receiving more than one superframe time at a wireless frequency point f1, then receiving more than one superframe time at a wireless frequency point f2, if no time mark signaling is received in the period, then determining that no main clock mobile station exists currently, then randomly selecting a multiframe in the next superframe, randomly selecting a time slot in the selected multiframe, sending the time mark signaling of the time slot by the wireless frequency point corresponding to the time slot, then sending the time mark signaling of the time slot by another wireless frequency point at the same time slot position of the next multiframe, and participating in election of the main clock mobile station if the mobile station receives the time mark signaling sent by other mobile stations in the current superframe period. The invention shortens the refreshing period of the synchronous clock and the emission duration of the synchronous clock.)

1. A method for searching the clock synchronization of a TDMA wireless ad hoc network is characterized by comprising the following steps:

the mobile station used as the transit node can use PDT standard communication specification of two-time-slot TDMA and can work in a TDMA duplex mode;

the frequency for wireless ad hoc network work has two single frequency points, namely a wireless frequency point f1 and a wireless frequency point f2, two time slots of a TDMA frame on the wireless frequency point f1 are respectively recorded as a time slot C0 and a time slot C1, two time slots of a TDMA frame on the wireless frequency point f2 are respectively recorded as a time slot C2 and a time slot C3, the time slot C0, the time slot C1, the time slot C2 and the time slot C3 are sequentially arranged to form a multiframe, and 32 multiframes are arranged together to form a superframe;

the mobile station which can be used as a transfer node elects a main clock mobile station through an election method, wherein the election method comprises the following steps:

after the mobile station serving as a transit node is powered on, the mobile station receives more than one superframe at the wireless frequency point f1, then receives more than one superframe at the wireless frequency point f2, if no time stamp signaling is received during the above period, it is assumed that there is no master clock mobile station currently, then randomly selecting a multiframe in a subsequent superframe, randomly selecting a time slot in the selected multiframe, sending a time scale signaling of the time slot by using a wireless frequency point corresponding to the time slot, then sending a time scale signaling of the time slot by using another wireless frequency point at the same time slot position of the next multiframe, wherein the time scale signaling comprises the current time slot position, the next time scale signaling transmission time slot position information, the transmitting party authority level and the identification code, if the mobile station receives the time mark signaling sent by other mobile stations in the current superframe period, the following operations are carried out:

judging whether other mobile stations have mobile stations with higher authority levels than the mobile stations, if so, quitting the election of the main clock mobile station, and stopping sending the time mark signaling;

if no mobile station with higher authority level than the self authority level exists, judging whether a mobile station with the same authority level as the self authority level exists, if so, judging whether a mobile station with a multiframe where the time mark signaling is sent is behind the multiframe where the time mark signaling is sent by the self, if so, quitting the election of the main clock mobile station, stopping sending the time mark signaling, otherwise, successfully electing, serving as the main clock mobile station, and continuously sending the time mark signaling.

2. The method for searching for the clock synchronization of the TDMA wireless ad hoc network according to claim 1, wherein each mobile station serving as a transit node is pre-configured with a corresponding permission level value, wherein the permission level values are 1, 2 and 3, respectively, the larger the value is, the higher the permission level is, the 3 represents the highest permission level, and the 1 represents the lowest permission level.

3. A method for searching for the synchronization of the clock in a TDMA wireless ad hoc network as claimed in claim 2, wherein 32 multiframes in said one superframe are sequentially numbered 0-31 in time sequence, and the multiframe randomly selected by the mobile station as the transmission timing signaling must satisfy the following condition: the result of modulo operation of the multiframe sequence number and the mobile station permission level value is equal to the mobile station permission level value.

4. A method for clock synchronization searching in a TDMA wireless ad hoc network as claimed in claim 1, 2 or 3, wherein the position of the next time scale signalling transmission slot in said time scale signalling is determined by: randomly selecting a multiframe in a subsequent superframe, and randomly selecting a time slot in the selected multiframe, wherein the time slot position is the time slot position for next time scale signaling transmission, and the same time slot position as that of the next subsequent multiframe is the time slot position for next time scale signaling transmission.

5. A method for TDMA wireless ad hoc network clock synchronization searching according to claim 1, 2, 3 or 4, wherein after a master clock mobile station is elected, a first class transit mobile station is selected by:

after receiving the time mark signaling sent by the master clock mobile station, the other mobile stations which can be used as the transit nodes, randomly selecting a multiframe from the time of receiving the time mark signaling sent by the main clock mobile station to the next time of receiving the time mark signaling sent by the main clock mobile station, wherein the selected multiframe must be different from the multiframe position of the time mark signaling sent by the main clock mobile station, randomly selecting a time slot in the selected multiframe, sending a first-level transit time mark signaling of the time slot by a wireless frequency point corresponding to the time slot, and then sending a first-level transit time mark signaling of the time slot by another wireless frequency point at the same time slot position of the next multiframe, wherein the first-level transit time mark signaling comprises the current time slot position, the next first-level transit time mark signaling transmission time slot position information, the transmitting party authority level, the identification code, the main clock mobile station identification code and the received signal quality information;

after receiving the first-stage transfer time mark signaling, the main clock mobile station selects the first-stage transfer mobile station and sends a designated signaling to the selected first-stage transfer mobile station.

6. The method according to claim 5, wherein the master clock mobile station preferentially selects the mobile station with higher authority level as the first-class relay mobile station, and preferentially selects the mobile station within the optimal relay range as the first-class relay mobile station if the authority levels are the same.

7. The method according to claim 5, wherein the specific signaling sent from the master mobile station to the primary relay mobile station further includes information on whether to select the secondary relay mobile station, and if the primary relay mobile station receives the information on the selected secondary relay mobile station, the secondary relay mobile station is selected, and the method comprises:

other mobile stations which can be used as transfer nodes, after receiving a first transfer time mark signal sent by a first transfer mobile station, randomly selecting a multiframe from the time of receiving the first transfer time mark signal sent by the first transfer mobile station to the next time of receiving the first transfer time mark signal sent by the first transfer mobile station, wherein the selected multiframe is different from the multiframe position of the time mark signal sent by the main clock mobile station, randomly selecting a time slot in the selected multiframe, sending a second transfer time mark signal of the time slot by a wireless frequency point corresponding to the time slot, and then sending a second transfer time mark signal of the time slot by another wireless frequency point at the same time slot position of the next multiframe, wherein the second transfer time mark signal comprises the current time slot position, the next second transfer time mark signal transmission time slot position information, the transmitting party authority level, the self identity code, The first-level transfer mobile station identity identification code and the received signal quality information;

and after the first-level transfer mobile station receives the second-level transfer time mark signaling, selecting the second-level transfer mobile station and sending the designated signaling to the selected second-level transfer mobile station.

8. The method as claimed in claim 1, wherein after the normal mobile station is powered on, it first receives more than one superframe at f1, then receives more than one superframe at f2, and after receiving the timing mark signaling, it scans and receives the superframe according to the superframe timed by the mobile station in the main clock, i.e. it scans and receives the superframe according to slot C0, slot C1, slot C2, and slot C3.

9. The method of claim 8, wherein when the ordinary mobile station needs to transmit, it transmits uplink in the time slot C0 according to the timing of the primary clock mobile station, and the ordinary mobile station that does not receive the timing information of the primary clock mobile station prohibits transmission.

Technical Field

The invention relates to the technical field of TDMA wireless ad hoc networks, in particular to a method for searching clock synchronization of a TDMA wireless ad hoc network.

Background

In the area without network coverage, a group of mobile terminals uses a plurality of channels, and selects a transit mobile terminal as a transit node through competition to form a temporary service multi-hop network. Several transit mobile terminals can transmit the service (such as voice) to remote place to form a service area with larger coverage area.

The election of the relay mobile terminal of the ad hoc network is an important link of the network, and the mobile station adopting the TDMA technical specification also has the requirement of clock synchronization. The completion of the two links generally takes a long time and occupies a large resource.

In the DMR standard using the 2-slot TDMA technique, there is a method of using what is called a TDMA express mode, among which there is a clock synchronization method of a TDMA express network. However, the refresh period of the synchronous clock is long, and the requirement of fast networking required by the ad hoc network is not met.

Disclosure of Invention

In order to solve the technical problem, the invention provides a method for searching the synchronization of the clock of the TDMA wireless ad hoc network, which shortens the refreshing period of the synchronous clock and the transmission duration of the synchronous clock.

In order to solve the problems, the invention adopts the following technical scheme:

the invention discloses a method for searching a TDMA wireless ad hoc network clock synchronization, which comprises the following steps:

the mobile station used as the transit node can use PDT standard communication specification of two-time-slot TDMA and can work in a TDMA duplex mode;

the frequency for wireless ad hoc network work has two single frequency points, namely a wireless frequency point f1 and a wireless frequency point f2, two time slots of a TDMA frame on the wireless frequency point f1 are respectively recorded as a time slot C0 and a time slot C1, two time slots of a TDMA frame on the wireless frequency point f2 are respectively recorded as a time slot C2 and a time slot C3, the time slot C0, the time slot C1, the time slot C2 and the time slot C3 are sequentially arranged to form a multiframe, and 32 multiframes are arranged together to form a superframe;

the mobile station which can be used as a transfer node elects a main clock mobile station through an election method, wherein the election method comprises the following steps:

after the mobile station serving as a transit node is powered on, the mobile station receives more than one superframe at the wireless frequency point f1, then receives more than one superframe at the wireless frequency point f2, if no time stamp signaling is received during the above period, it is assumed that there is no master clock mobile station currently, then randomly selecting a multiframe in a subsequent superframe, randomly selecting a time slot in the selected multiframe, sending a time scale signaling of the time slot by using a wireless frequency point corresponding to the time slot, then sending a time scale signaling of the time slot by using another wireless frequency point at the same time slot position of the next multiframe, wherein the time scale signaling comprises the current time slot position, the next time scale signaling transmission time slot position information, the transmitting party authority level and the identification code, if the mobile station receives the time mark signaling sent by other mobile stations in the current superframe period, the following operations are carried out:

judging whether other mobile stations have mobile stations with higher authority levels than the mobile stations, if so, quitting the election of the main clock mobile station, and stopping sending the time mark signaling;

if no mobile station with higher authority level than the self authority level exists, judging whether a mobile station with the same authority level as the self authority level exists, if so, judging whether a mobile station with a multiframe where the time mark signaling is sent is behind the multiframe where the time mark signaling is sent by the self, if so, quitting the election of the main clock mobile station, stopping sending the time mark signaling, otherwise, successfully electing, serving as the main clock mobile station, and continuously sending the time mark signaling.

In the scheme, a method for a mobile station, which can be used as a transit node, to randomly select a time slot in a selected multiframe, send a time mark signaling of the time slot at a wireless frequency point corresponding to the time slot, and then send the time mark signaling of the time slot at the same time slot position of the next multiframe at another wireless frequency point is as follows:

if the selected time slot is the time slot C0 or the time slot C1, the corresponding wireless frequency point is the wireless frequency point f1, the mobile station sends a time mark signaling of one time slot at the selected time slot by the wireless frequency point f1, and then sends the time mark signaling of one time slot at the same time slot position of the next multiframe by the wireless frequency point f 2;

if the selected time slot is the time slot C2 or the time slot C3, the corresponding wireless frequency point is the wireless frequency point f2, the mobile station sends the time mark signaling of one time slot at the wireless frequency point f2 in the selected time slot, and then sends the time mark signaling of one time slot at the wireless frequency point f1 in the same time slot position of the next multiframe.

The time slot position of the time mark signaling sent by the mobile station which can be used as the transit node at each time is randomly selected, so that the time mark signaling can be prevented from colliding with the time mark signaling sent by other mobile stations which can be used as the transit node. After many cycles, only one mobile station will eventually transmit the timing mark signaling, which is the preferred master clock mobile station. The method shortens the refreshing period of the synchronous clock and the emission duration of the synchronous clock.

Preferably, each mobile station serving as a transit node is provided with a corresponding permission level value in advance, the permission level values are respectively 1, 2 and 3, the larger the value is, the higher the permission level is, 3 represents the highest permission level, and 1 represents the lowest permission level.

Preferably, 32 multiframes in the superframe are sequentially numbered as 0-31 in time sequence, and the multiframes randomly selected by the mobile station as the sending time scale signaling must satisfy the following conditions: the result of modulo operation of the multiframe sequence number and the mobile station permission level value is equal to the mobile station permission level value. The time sequences which can be selected by the mobile stations with the three authorities are distinguished, collision is avoided, and the selection time is shortened.

Preferably, the position of the time slot for transmitting the next time stamp signaling in the time stamp signaling is determined by the following method: randomly selecting a multiframe in a subsequent superframe, and randomly selecting a time slot in the selected multiframe, wherein the time slot position is the time slot position for next time scale signaling transmission, and the same time slot position as that of the next subsequent multiframe is the time slot position for next time scale signaling transmission.

Preferably, after the master clock mobile station is selected, the one-stage relay mobile station is selected by the following method:

after receiving the time mark signaling sent by the master clock mobile station, the other mobile stations which can be used as the transit nodes, randomly selecting a multiframe from the time of receiving the time mark signaling sent by the main clock mobile station to the next time of receiving the time mark signaling sent by the main clock mobile station, wherein the selected multiframe must be different from the multiframe position of the time mark signaling sent by the main clock mobile station, randomly selecting a time slot in the selected multiframe, sending a first-level transit time mark signaling of the time slot by a wireless frequency point corresponding to the time slot, and then sending a first-level transit time mark signaling of the time slot by another wireless frequency point at the same time slot position of the next multiframe, wherein the first-level transit time mark signaling comprises the current time slot position, the next first-level transit time mark signaling transmission time slot position information, the transmitting party authority level, the identification code, the main clock mobile station identification code and the received signal quality information;

after receiving the first-stage transfer time mark signaling, the main clock mobile station selects the first-stage transfer mobile station and sends a designated signaling to the selected first-stage transfer mobile station.

The position of the next one-level transit time mark signaling transmission time slot in the one-level transit time mark signaling is determined by the following method: randomly selecting a multiframe in a subsequent superframe, and randomly selecting a time slot in the selected multiframe, wherein the time slot position is the same as that of the next multiframe, namely the next-stage transit time mark signaling transmission time slot position.

The multiframe randomly selected by the mobile station as the signaling for sending the first-level transit time mark must satisfy the following conditions: the result of modulo operation of the multiframe sequence number and the mobile station authority level value is equal to the mobile station authority level value and avoids the multiframe position of the time mark signaling sent by the main clock mobile station.

Preferably, the master mobile station preferentially selects a mobile station having a higher authority level as the primary relay mobile station, and preferentially selects a mobile station located within the optimal relay range as the primary relay mobile station when the authority levels are the same. The mobile stations within the optimum relay range are the mobile stations with better received signal quality and a longer distance from the master clock mobile station.

Preferably, the designated signaling sent by the master mobile station to the primary relay mobile station further includes information on whether to select the secondary relay mobile station, and if the primary relay mobile station receives the information on the selected secondary relay mobile station, the secondary relay mobile station is selected, and the method includes:

other mobile stations which can be used as transfer nodes, after receiving a first transfer time mark signal sent by a first transfer mobile station, randomly selecting a multiframe from the time of receiving the first transfer time mark signal sent by the first transfer mobile station to the next time of receiving the first transfer time mark signal sent by the first transfer mobile station, wherein the selected multiframe is different from the multiframe position of the time mark signal sent by the main clock mobile station, randomly selecting a time slot in the selected multiframe, sending a second transfer time mark signal of the time slot by a wireless frequency point corresponding to the time slot, and then sending a second transfer time mark signal of the time slot by another wireless frequency point at the same time slot position of the next multiframe, wherein the second transfer time mark signal comprises the current time slot position, the next second transfer time mark signal transmission time slot position information, the transmitting party authority level, the self identity code, The first-level transfer mobile station identity identification code and the received signal quality information;

and after the first-level transfer mobile station receives the second-level transfer time mark signaling, selecting the second-level transfer mobile station and sending the designated signaling to the selected second-level transfer mobile station.

The position of the next secondary transit time mark signaling transmission time slot in the secondary transit time mark signaling is determined by the following method: randomly selecting a multiframe in a subsequent superframe, and randomly selecting a time slot in the selected multiframe, wherein the time slot position is the time slot position of the next secondary transit time mark signaling transmission, and the time slot position is the same as the time slot position of the next multiframe.

The multiframe randomly selected by the mobile station as the signaling for sending the secondary transit time mark must satisfy the following conditions: the result of modulo operation of the multiframe sequence number and the mobile station authority level value is equal to the mobile station authority level value and avoids the multiframe position of the time mark signaling sent by the main clock mobile station.

Preferably, after the normal mobile station is powered on, the normal mobile station receives more than one superframe at the wireless frequency point f1, then receives more than one superframe at the wireless frequency point f2, and performs code scanning reception according to the superframe timed by the mobile station of the main clock after receiving the time scale signaling, namely performs multiframe cyclic scanning reception according to the time slot C0, the time slot C1, the time slot C2 and the time slot C3.

Preferably, when the normal mobile station needs to transmit, it transmits uplink in the channel of time slot C0 according to the timing of the main clock mobile station, and the normal mobile station which does not receive the timing information of the main clock mobile station prohibits transmission.

The invention has the beneficial effects that: the refresh period of the synchronous clock and the transmission duration of the synchronous clock are shortened, and the transfer mobile station is elected at the same time when the synchronous clock is established.

Drawings

Fig. 1 is a schematic diagram of the structure of a superframe of the embodiment.

Detailed Description

The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings.