CN103746878B - Simulation system for measuring transmission time of SpaceWire data packets - Google Patents

Abstract

The invention discloses a simulation system for measuring the transmission time of a SpaceWire data packet. The simulation system includes a wormhole router module (1) with a time window, a time master control node module (2) and a terminal application node module (3) , the three modules form an aerospace communication network based on the SpaceWire bus standard communication. The terminal application node module (3) is used to generate two types of SpaceWire data packets, synchronize the time through the simulation system provided by the time master node module (2), and complete the data packets in the wormhole router module (1) with a time window Statistics of transmission time and transmission delay time. The simulation system of the invention is used to measure the transmission time and transmission delay time of the SpaceWire data packet based on the SpaceWire bus standard, and the obtained time information can improve the performance of the aerospace communication network.

Description

A simulation system for measuring the transmission time of SpaceWire data packets

technical field

The invention relates to the simulation field of aerospace communication network, more particularly, refers to a simulation system for measuring the transmission delay of SpaceWire data packets.

Background technique

SpaceWire (translated as space bus) bus is a serial, high-speed, point-to-point, full-duplex spaceborne data network standard (ECSS-E-ST-50-12C, 31July2008), which is a multi-source, asynchronous, event-triggered communication Network, it is difficult to guarantee the end-to-end delay of message transmission. If the message attributes of some nodes in the network are known in advance, such as time, size and other information, their transmission is planned and scheduled according to a fixed time window, a time-triggered message network can be formed, and the speed of message transmission in the network can be greatly improved. Certainty.

The end-to-end delay of SpaceWire data packet transmission is a very important measurement index in network analysis, which reflects the real-time nature of the network. There are many methods for measuring message transmission delay, among which network emulation is a common choice. Network simulation uses mathematical modeling and statistical analysis to simulate network behavior. It can easily modify the model and perform simulation. It is suitable for predicting network performance and providing reliable quantitative basis for network planning and design.

Based on software protocol simulation to simulate the SpaceWire network communication mechanism, measure the end-to-end delay of event-triggered message transmission in the SpaceWire network, there is a lack of simulation system based on time-triggered messages and planning the scheduling schedule of wormhole routers.

Contents of the invention

The purpose of this invention is to propose a kind of simulation system of measuring the transmission time of SpaceWire data packet, this simulation system is to solve the simulation problem of time-triggered message in SpaceWire bus network, the scheduling time of router is planned, utilize time window width and window Wide size conditions are used to process the forwarding of SpaceWire data packets, priority is given to time-triggered SpaceWire data packets, and the transmission time of time-triggered SpaceWire data packets is guaranteed. For the SpaceWire data packet triggered by the event, the condition of the window width is used for forwarding.

The invention relates to a simulation system for measuring the transmission time of the SpaceWire data packet. The simulation system constructs an aerospace communication network according to the SpaceWire bus standard communication. The simulation system includes a wormhole router with a time window (1), a time master node module (2) and a terminal application node module (3).

The wormhole router (1) with a time window includes a wormhole routing unit (11), a time window setting unit (12) and a data packet cache unit (13).

The wormhole routing unit (11) is used for forwarding SpaceWire data packets triggered by time and SpaceWire data packets triggered by events.

The time window setting unit (12) determines the sending sequence of the data packets in combination with the time window width and the size of the window width.

The data packet buffer unit (13) is used for temporarily saving the SpaceWire data packets triggered by time and the SpaceWire data packets triggered by events.

The time master control node module (2) includes a time synchronization control unit (21) and a time master control receiving unit (22). The time synchronization control unit (21) is used to generate a synchronization time code TM_Time_Code, and broadcast it to the aerospace communication network based on SpaceWire bus standard communication. When the time master control node module (2) serves as the purpose, the time master control receiving unit (22) is used to receive time-triggered SpaceWire data packets and event-triggered SpaceWire data packets.

The terminal application node module (3) includes a terminal application sending unit (31) and a terminal application receiving unit (32).

When the terminal application node module (3) serves as the source node, the terminal application node module (3) sends time-triggered SpaceWire data packets and event-triggered SpaceWire data packets through the terminal application sending unit (31). Sets the T _interval for time-triggered SpaceWire packets.

When the terminal application node module (3) acts as an intermediate node, the terminal application node module (3) forwards time-triggered SpaceWire data packets and event-triggered SpaceWire data packets through the terminal application sending unit (31) according to the transmission link.

When the terminal application node module (3) serves as the destination node, the terminal application node module (3) receives time-triggered SpaceWire data packets and event-triggered SpaceWire data packets through the terminal application receiving unit (32).

In the simulation system for measuring the transmission time of the SpaceWire data packet, in the time window setting unit (12), the interval between the time window widths of any two time-triggered SpaceWire data packets is called the window width interval CH, The window width interval CH is used to forward the SpaceWire data packet triggered by the event. The time-triggered SpaceWire data packets are sent according to the sequence _generated by the AT at the generation time. The event-triggered SpaceWire data packets are sent according to the order in which the BT _{is generated} at the generation time and whether the window width size condition of the window interval is satisfied.

The present invention measures the advantage of the emulation system of SpaceWire packet transmission delay and is:

①The simulation system of the present invention has transformed the traditional wormhole router model of SpaceWire, increased the data packet cache mechanism, increased the router scheduling time window, and realized the simulation control of time-triggered messages, thereby obtaining a scheduling of processing time-triggered messages router model.

② The simulation system of the present invention is compatible with event-triggered and time-triggered message transmission mechanisms, and is applicable to the simulation of various network scenarios, such as: event-triggered network, time-triggered network, event-triggered and time-triggered compatible network. The simulation results can be fed back to the designer to evaluate the transmission performance of the network.

③The present invention can also complete the simulation of the standard SpaceWire network. When the network does not contain time-triggered data packets, all of them are event-triggered data packets, which is consistent with the network specified by the standard protocol.

Description of drawings

Fig. 1 is a structural diagram of a simulation system for measuring the transmission time of SpaceWire data packets according to the present invention.

FIG. 2A is a structural schematic diagram of a time window width and a window width interval.

FIG. 2B is a structural schematic diagram of multiple time windows and window intervals.

FIG. 2C is another structural schematic diagram of multiple time windows and window intervals.

FIG. 2D is another structural schematic diagram of multiple time windows and window intervals.

Fig. 3 is a simulation flow chart of the simulation system for measuring the transmission time of SpaceWire data packets in the present invention.

Figure 4 is a schematic diagram of an aerospace communication network based on the SpaceWire standard protocol.

Figure 5 is a schematic diagram of the simulation results.

detailed description

The present invention will be further described in detail with reference to the accompanying drawings and embodiments.

The present invention is to realize in an aerospace communication network based on the SpaceWire bus standard communication, simulate the transmission time of the SpaceWire data packet from end-to-end transmission, and measure the transmission end-to-end of the SpaceWire data packet by the transmission time obtained by the simulation delay.

In the present invention, the simulation is performed based on the platform of matlab (version number 7.13).

Referring to FIG. 1 , the simulation system of the present invention includes a wormhole router 1 with a time window, a time master node module 2 and a terminal application node module 3 . Wherein, the wormhole router 1 with time window includes a wormhole routing unit 11 , a time window setting unit 12 and a data packet cache unit 13 . Wherein, the time master node module 2 includes a time synchronization control unit 21 and a time master receiving unit 22 . Wherein, the terminal application node module 3 includes a terminal application sending unit 31 and a terminal application receiving unit 32 .

In the present invention, in the aerospace communication network based on the SpaceWire bus standard communication, the time master control node module 2 can be used to receive time-triggered SpaceWire data packets and event-triggered SpaceWire data packets, and become a destination node.

In the present invention, the terminal application node module 3 can be used to send the SpaceWire data packet triggered by time and the SpaceWire data packet triggered by event on the one hand, and become a source node; on the other hand, it can be used to receive the SpaceWire data packet triggered by time and the event triggered The SpaceWire data packet becomes the destination node. The process of transmitting a SpaceWire data packet from a source node to a destination node is called a transmission link, and nodes on the transmission link except the source node and the destination node are called intermediate nodes. The intermediate node may be a wormhole router 1 with a time window and/or a terminal application node module 3 .

The time-triggered SpaceWire data packet refers to triggering the transmission of the SpaceWire data packet according to the set fixed sending time _interval T of the data packet. In detail, when in the terminal application node module 3, if the T _interval =0.5 second is set to send the SpaceWire packet, then the terminal application sending unit 31 in the terminal application node module 3 will regularly SpaceWire packets to time master node module 2.

The SpaceWire data packet triggered by the event refers to irregular SpaceWire data packet transmission.

In the present invention, the SpaceWire data packet contains type _time , type _Event , size, src, dest, num, eop, T _generation ; wherein type _time , type _Event , size, src and dest constitute the header src_node of the SpaceWire data packet. The data blocks in a SpaceWire data packet are set to num=50; in the description _generated at the generation time T, since there are the type type time of the SpaceWire data packet triggered by _time and the type type _Event of the SpaceWire data packet triggered by the event, so The generation time of data packets of type _time type is recorded as AT _generation , and the generation time of data packets of type _Event type is recorded as BT _generation .

Time Master Node Module 2

In the present invention, the time synchronization control unit 21 in the time master node module 2 is used to generate a synchronization time code TM_Time_Code, and broadcast it to the aerospace communication network based on the SpaceWire bus standard communication. After the terminal application node module 3 and the wormhole router 1 with a time window receive the synchronous time code TM_Time_Code, the unified time of the entire aerospace communication network based on the SpaceWire bus standard communication is guaranteed.

The synchronization time code TM_Time_Code generated by the time synchronization control unit 21 of the present invention is used to control the time synchronization of the aerospace communication network, and the TM_Time_Code is the same as the Time-Code in the SpaceWire standard protocol.

When the time master control node module 2 is used as the destination node, the time master control node module 2 receives time-triggered SpaceWire data packets and event-triggered SpaceWire data packets through the time master control receiving unit 22 .

In the present invention, the time synchronization control unit 21 in the time master node module 2 generates a time code and broadcasts it to the entire network to control the time synchronization of the entire simulation network. After the time master receiving unit 22 completes the processing of the SpaceWire data packet triggered by the time received and the SpaceWire data packet triggered by the event, the _generation time T of the SpaceWire data packet is extracted and the time T _end when the SpaceWire data packet arrives at the destination node , so that the transmission time ET=T _end -T _generation of the SpaceWire data packet from the source node to the destination node can be calculated.

End Application Node Module 3

Before the simulation, set the identity of the terminal application node module 3 (source node, intermediate node or destination node), send the type of SpaceWire data packet (time-triggered SpaceWire data packet or event-triggered SpaceWire data packet), and The node module 3 sets the time interval T _interval of the time-triggered SpaceWire data packet, and then sets the transmission rate of the SpaceWire data packet (time-triggered SpaceWire data packet and event-triggered SpaceWire data packet), the _generation time T of the data packet, The size of the packet size. If the terminal application node modules 3 are used to generate all time-triggered messages, a time-triggered network is formed; if the terminal application node modules 3 are used to generate all event-triggered messages, an event-triggered network is formed; Messages, partly generating time-triggered messages, are event-time-triggered compatible networks.

The terminal application node module 3 ensures that during the simulation process, the terminal application node module 3 is synchronized with the network time in the aerospace communication network when receiving and sending SpaceWire data packets according to the received synchronization time code TM_Time_Code.

When the terminal application node module 3 serves as the source node, the terminal application node module 3 sends the time-triggered SpaceWire data packet and the event-triggered SpaceWire data packet through the terminal application sending unit 31 . Sets the T _interval for time-triggered SpaceWire packets.

When the terminal application node module 3 acts as an intermediate node, the terminal application node module 3 forwards the time-triggered SpaceWire data packet and the event-triggered SpaceWire data packet according to the transmission link through the terminal application sending unit 31 .

When the terminal application node module 3 serves as the destination node, the terminal application node module 3 receives the time-triggered SpaceWire data packet and the event-triggered SpaceWire data packet through the terminal application receiving unit 32 .

Wormhole Router with Time Window 1

In the present invention, in order to ensure the network transmission of time-triggered SpaceWire data packets and event-triggered SpaceWire data packets in the space communication network, an additional wormhole router (ie, wormhole routing unit 11) is added The time window setting unit 12 and the data packet cache unit 13, therefore, the wormhole router is called a wormhole router with a time window in the present invention.

The wormhole routing unit 11 is used to complete the forwarding of time-triggered SpaceWire data packets and event-triggered SpaceWire data packets.

The time window setting unit 12 determines the sending order of the data packets in combination with the time window width and the size of the window width.

The data packet buffer unit 13 is used for temporarily saving the time-triggered SpaceWire data packets and the event-triggered SpaceWire data packets. Because each input port of each router has a buffer queue for buffering SpaceWire data packets. When the header of the data packet arrives at the router, the router obtains the output port required for its transmission through the destination node information carried in the data packet. If the output port is busy at this time, the data packet should be cached in the cache queue of the router. , the router sends data packets from the cache queue for forwarding after the output port is idle. In the present invention, the data packets buffered by the data packet cache unit 13 are because the time window setting unit 12 controls the forwarding time of the data packets according to the time window width.

In the present invention, the time window width of the SpaceWire data packet triggered by time is recorded as AH, and the The time window width of the SpaceWire packet triggered by the event is denoted as BH, the size represents the size of a SpaceWire packet, and c represents the link transmission rate set by the simulation. The interval between the time windows of any two time-triggered SpaceWire data packets is called the window width interval CH, and the window width interval CH is used to forward the event-triggered SpaceWire data packets. The time-triggered SpaceWire data packets are sent according to the sequence _generated by AT at the generation time. The event-triggered SpaceWire data packets are sent according to the order in which the BT _{is generated} at the generation time and whether the window width size condition of the window interval is satisfied. In the present invention, the window width condition of the window width interval is: if CH≥BH, then forward the SpaceWire data packet triggered by the event, if CH<BH, then wait for the next window width interval, and further judge the next Whether the window size of a window interval meets the time window size of the SpaceWire data packet triggered by the event to be forwarded. In the present invention, for those whose generation time overlaps, the SpaceWire data packets are forwarded according to the size of the time window, the data packets with a small time window are sent first, and the data packets with a large time window are sent later.

As shown in Figure 2A, in a network transmission cycle T _period , the wormhole router 1 with a time window receives two time-triggered SpaceWire data packets successively, that is, the previous time-triggered SpaceWire data packet and the latter time-triggered SpaceWire data packet. SpaceWire packets;

Extract the generation moment of said time-triggered SpaceWire packet from the previous time-triggered SpaceWire packet and packet size size, and calculate the time window width

Extract the generation moment of said time-triggered SpaceWire packet from the latter time-triggered SpaceWire packet and packet size size, and calculate the time window width

After sorting the generation time, there is a window width interval between ^before AH and ^after AH

For the sending of the two time-triggered SpaceWire data packets, the time-triggered SpaceWire data packets are forwarded successively according to their respective generation times.

Referring to FIG. 2B , FIG. 2C , and FIG. 2D , in a network transmission cycle T _period , the wormhole router 1 with a time window will receive multiple SpaceWire data packets.

For example, the SpaceWire data packet triggered by the first time is recorded as SWT ₁ , the SpaceWire data packet triggered by the second time is recorded as SWT ₂ , ..., the SpaceWire data packet triggered by the penultimate time is recorded as SWT _X-1 , and the last A time-triggered SpaceWire packet is denoted as SWT _X , the first event-triggered SpaceWire packet is denoted as SWE ₁ , the second event-triggered SpaceWire packet is denoted as SWE ₂ , ..., the last event-triggered SpaceWire data The packet is recorded as SWE _Y ; X represents the identification number of the time-triggered SpaceWire data packet, for the convenience of explanation, SWT _X is also called any time-triggered SpaceWire data packet; Y represents the identification number of the event-triggered SpaceWire data packet, for convenience Note that SWE _Y is also known as any SpaceWire packet triggered by an event.

In the time window setting unit 12, the following generation time and time window width need to be obtained:

The generation time of SWT ₁ is recorded as The time window width of SWT ₁ is recorded as

The generation moment of SWT ₂ is recorded as The time window width of SWT ₂ is recorded as

The generation time of SWT _X-1 is recorded as The time window width of SWT _X is recorded as

The generation moment of SWT _X is recorded as The time window width of SWT _X is recorded as

The generation time of SWE ₁ is recorded as The time window width of SWE ₁ is recorded as

The generation time of SWE ₂ is recorded as The time window width of SWE ₂ is recorded as

The generation time of SWE _Y is recorded as The time window width of SWE _Y is denoted as

Referring to Figure 2B, the order of generation time is: and

As shown in Figure 2B, the time window width overlaps as follows:

(1) backend with front-end overlap;

(2) backend with front-end overlap;

(3) backend with front-end overlap;

(4) backend with front-end overlap;

(5) backend with front overlap.

Referring to Figure 2B, there is a window width interval of: and There is a window width interval between and There is a window width interval between

The sending sequence of data packets according to the time window width is: SWT ₁ →SWT _X →SWT _X-1 →SWE ₂ →SWT ₂ →SWE ₁ →SWE _Y. because The window width is greater than or equal to the time window width of SWE ₂ So SWE ₂ will be emitted before SWT ₂ . if The window width of is smaller than the time window width of SWE ₂ Then SWE ₂ will wait for a satisfying to be sent SWE ₂ .

Referring to Figure 2C, the order of generation time is: and

As shown in Figure 2C, the time window width overlaps as follows: backend with front overlap.

Referring to Figure 2C, there is a window width interval of: and There is a window width interval between and There is a window width interval between and There is a window width interval between

The sending sequence of data packets according to the time window width is: SWT ₁ →SWE ₁ →SWT _X-1 →SWE ₂ →SWT ₂ →SWT _X →SWE _Y. if Can satisfy the time window width at the same time and Then the sending sequence of data packets is: SWT ₁ →SWE ₁ →SWT _X-1 →SWE ₂ →SWE _Y →SWT ₂ →SWT _X .

As shown in Figure 2D, the order of generation time is: and

As shown in Figure 2D, the time window width overlaps as follows: backend with front overlap.

Referring to Figure 2D, there is a window width interval of: and There is a window width interval between and There is a window width interval between and There is a window width interval between

The sending sequence of data packets according to the time window width is: SWT ₁ →SWE ₁ →SWT _X-1 →SWE ₂ →SWT ₂ →SWE _Y →SWT _X .

In the present invention, since the event-triggered SpaceWire data packet needs to wait for a suitable time window during transmission, there is a transmission delay time for the event-triggered SpaceWire data packet. The transmission delay time can be obtained more conveniently by comparing the size of the time window width.

In the present invention, by calculating the sum of the time window width of the SpaceWire data packet triggered by the time obtained and the time window width of the SpaceWire data packet triggered by the event, the data packet transmission time in a network cycle can be obtained more conveniently .

In the present invention, the performance of the aerospace communication network based on the SpaceWire bus standard communication can be obtained by analyzing the transmission delay time and the data packet transmission time.

In the present invention, the sending sequence of the data packets is controlled by setting the time window width in the time window setting unit 12, which improves the real-time transmission performance of the time-triggered SpaceWire data packets in the aerospace communication network.

The wormhole router 1 with time window guarantees the synchronization with the network time in the aerospace communication network when forwarding the time-triggered SpaceWire data packets and event-triggered SpaceWire data packets according to the received synchronous time code TM_Time_Code.

Simulation process of aerospace communication network based on SpaceWire bus standard communication:

Step 1: Build an aerospace communication network based on SpaceWire bus standard communication with wormhole router 1 with time window, time master node module 2 and terminal application node module 3; set up the transmission link and data of the already constructed aerospace communication network packet transfer rate;

According to the requirements of the aerospace communication network, several terminal application nodes, a time master node, and several wormhole routers with time windows are selected and connected by communication links to form a network.

Referring to Figure 4, 5 terminal application nodes, 3 wormhole routers with time windows and 1 time master node form an aerospace communication network. The terminal application node is denoted by the symbol ES, the wormhole router with time window is denoted by the symbol WR, and the time master node is denoted by the symbol TM.

If the first terminal application node ES ₁ is set as the source node, and the time master node is set as the destination node TM, then the intermediate node is the first wormhole router WR ₁ with a time window, and the second wormhole router with a time window Router WR ₂ , so the transmission link is that ES ₁ sends data packets to WR ₁ , WR ₁ forwards data packets to WR _{2, and WR 2 forwards} data packets to TM. After the transmission link is determined, the data packet transmission time is _generated as ET=T _end −T.

Step 2: Configure the terminal application node module;

Set the type of SpaceWire packet, one is time-triggered SpaceWire packet, the other is event-triggered SpaceWire packet;

Set the time interval T _interval for time-triggered SpaceWire packets;

Set the packet size for time-triggered SpaceWire packets;

Set the packet size of the event-triggered SpaceWire packet;

Step 3: Configure the time master node module;

Set the initial time synchronization time code TM_Time_Code, and broadcast the TM_Time_Code in the aerospace communication network; use 0 as the reference time for each initial simulation;

Step 4: Configure the network cycle time of the wormhole router with time window, and start the simulation;

Step 5: The wormhole router with time window counts the time window width, and receives and forwards data packets;

The wormhole router with a time window first receives all data packets in a network cycle, then extracts the generation time and time window width of the data packets, and finally forwards the data packets sequentially according to the data packet type and window width judgment conditions.

The delay time for the delayed sending of data packets can be calculated through the calculated time window width and window width interval.

Step 6: Obtain the simulation result diagram through the simulation time, the number of data packets, and the type of data packets.

Example 1

As shown in Figure 5, it is a schematic diagram of the simulation results. Among them, the circle "○" represents the transmission time of the SpaceWire data packet triggered by time, and the circle represents the transmission time of a time-triggered SpaceWire data packet; the five-pointed star "☆" represents the transmission time of the SpaceWire data packet triggered by the event, and a five-star In the form of an event triggering the transmission time of a SpaceWire packet.

It can be seen that in the simulation period of 1.6s, a total of 20 times are measured to trigger the transmission time of SpaceWire data packets, all of which are 200ms (that is, 2×10 ^-4 s); a total of 19 events are measured to trigger the transmission time of SpaceWire data packets (200ms, 200ms, 200ms, 856ms, 200ms, 402ms, 200ms, 500ms, 200ms, 200ms, 490ms, 200ms, 200ms, 680ms, 200ms, 200ms, 200ms, 200ms, and 200ms, respectively). It can be seen that the transmission time of the time-triggered SpaceWire data packet is constant and the transmission delay is 0 because the time window width gives priority to the transmission of the time-triggered SpaceWire data packet. For event-triggered SpaceWire data packets, there may be a waiting process during transmission, so the transmission delay of some event-triggered SpaceWire data packets is not 0 (the transmission delay in this figure is that the transmission time of event-triggered SpaceWire data packets exceeds 200ms part), the transmission time of the SpaceWire data packet triggered by this part of the event will increase due to the size of the transmission delay, resulting in a different length of waiting time, in the simulation result diagram, the transmission time of the SpaceWire data packet triggered by this part of the event, due to the transmission Depending on the size of the delay, there are different degrees of upward shift.

The physical significance of application letters is as follows in the present invention:

T _interval Indicates the interval between the time window widths of any two time-triggered SpaceWire packets src_node Represents the header of a SpaceWire packet type _time Indicates the type of time-triggered SpaceWire packet AT _generated Indicates the time at which packets of type _time type are generated type _Event Indicates the type of SpaceWire packet triggered by the event BT _generation Indicates the generation time of the data packet for the type _Event type size Indicates the size of a SpaceWire packet src Indicates the source node of the SpaceWire packet dest Indicates the destination node of the SpaceWire packet num Indicates how many data blocks are in a SpaceWire packet T _head Indicates the starting time of receiving a SpaceWire data packet, called the packet head time T _end Indicates the end time of receiving a SpaceWire data packet, called the end time of the packet ET Indicates the time required to receive and complete a SpaceWire packet, called segment transmission time SWT _X Represents a SpaceWire packet triggered at any time x Indicates the identification number of the time-triggered SpaceWire packet SWE _Y Represents any SpaceWire packet triggered by an event Y Indicates the identification number of the SpaceWire packet that the event triggered

Claims (3)

1. a kind of analogue system of the transmission time of mensure spacewire packet, this analogue system is according to spacewire bus Standard traffic build space communication network it is characterised in that: this analogue system includes the Wormhole rou ting device with time window (1), time main controlled node module (2) and terminal applies node module (3)；

Wormhole rou ting device (1) with time window includes Wormhole rou ting unit (11), time window arranging unit (12) sum According to bag buffer unit (13)；

Wormhole rou ting unit (11) is used for completing the spacewire of the spacewire packet to time triggered and event triggering The forwarding of packet；

Time window arranging unit (12) binding time window width to judge the transmission order of packet with window width size；When described Between in window arranging unit (12), the time window width of the spacewire packet of time triggered is designated as ah, describedThe time window width of the spacewire packet of event triggering is designated as bh, describedsize Represent the size of a spacewire packet, c represents the link transmission rate of emulation setting；In the setting of described time window In unit (12), the interval between the time window width of the spacewire packet of any two time triggered is referred to as window width interval Ch, described window width is spaced ch and is used for forwarding the spacewire packet of event triggering；The spacewire packet of time triggered According to generation moment at_GeneratePriority be transmitted the spacewire packet of described time triggered；Event triggering Spacewire packet is according to generation moment bt_GeneratePriority and whether meet window width interval window width size condition be transmitted The spacewire packet of described event triggering；

Data pack buffer unit (13) triggers for the interim spacewire packet to time triggered and event Spacewire packet is preserved；

Time main controlled node module (2) includes time synchronized control unit (21) and time master control receiving unit (22)；Time Synchronous control unit (21) is used for generating lock in time code tm_time_code, and to based on the communication of spacewire bus standard Space communication network in broadcast；When time main controlled node module (2) is as purpose, time master control receiving unit (22) is used for Receive the spacewire packet of time triggered and the spacewire packet of event triggering；

Terminal applies node module (3) includes terminal applies transmitting element (31) and terminal applies receiving unit (32)；

When terminal applies node module (3) is as source node, terminal applies node module (3) passes through terminal applies transmitting element (31) the spacewire packet triggering the spacewire packet and event to send time triggered；Setting time triggered The t of spacewire packet_Interval, described t_IntervalIt is that the packet setting fixes transmission time interval；

When terminal applies node module (3) is as intermediate node, terminal applies node module (3) is sent single by terminal applies First (31) carry out the spacewire packet of forwarding time triggering and the spacewire data of event triggering according to transmission link Bag；

When terminal applies node module (3) is as destination node, terminal applies node module (3) is received single by terminal applies The spacewire packet that first (32) trigger come the spacewire packet and event to receive time triggered.

2. the transmission time of mensure spacewire packet according to claim 1 analogue system it is characterised in that: This analogue system is emulated based on matlab platform.

3. the transmission time of mensure spacewire packet according to claim 1 analogue system it is characterised in that: The simulation process of this analogue system is:

Step one: communicated the Wormhole rou ting device (1) with time window, time main controlled node based on spacewire bus standard Module (2) and terminal applies node module (3) build a space communication network；The space communication network having been built up is set Transmission link and the transfer rate of packet；

Step 2: configurating terminal application node module；

The type of setting spacewire packet, a kind of is time triggered spacewire packet, and another kind is event triggering Spacewire packet；

The t of setting time triggered spacewire packet_Interval, described t_IntervalIt is that the packet setting fixes transmission time interval；

The data package size of setting time triggered spacewire packet；

Setting event triggers the data package size of spacewire packet；

Step 3: setup time main controlled node module；

Time synchronized control unit (21) is used for generating lock in time code tm_time_code, and by this tm_time_code in boat Broadcasted in its communication network；Each time initially emulate when on the basis of 0 the time；

Step 4: the network cycle time of the Wormhole rou ting device with time window for the configuration, emulation starts；

Step 5: with the Wormhole rou ting device timing statisticses window width of time window, and receive, forward packet；

Wormhole rou ting device with time window first receives all packets in a network cycle, then extracts packet The generation moment, time window width, last to forward packet successively according to type of data packet and window width size Rule of judgment；

The time delay that packet is delayed by transmission can be calculated by the time window width counting, window width interval；

Step 6: simulation result figure is obtained by simulation time, packet number, type of data packet.