CN101340209B - Method for channel hopping and RF interference resistance in industrial radio network - Google Patents
Method for channel hopping and RF interference resistance in industrial radio network Download PDFInfo
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Abstract
The invention provides a method of radio frequency interference resistance of hop channel in industrial wireless networks and relates to industrial wireless communication networks. The invention is based on the adding of hop channel information and beacon frames of communication protocols of the industrial wireless networks; a coordinator generates and broadcasts hop channel sequences of a system to all devices of a whole network and the hop channel information which contains take-off points of the system and the take-off points of an adjacency system is added into the load of the beacon frames; a router and a terminal device analyze the beacon frames and an unused take-off point is selected as the present take-off point; the coordinator and the router dynamically evaluate the channels of the networks and define the interfered channels by packet loss rates; the coordinator shields the interfered channels; a next channel of the interfered channels in the hop channel sequences replaces the position of the interfered channels in the hop channel sequences; the radio frequency interference between industrial wireless network systems within the scope of the same radio frequency can be effectively avoided. The method can greatly improve the coexistence of industrial wireless network communication environments and the anti-interference capability.
Description
Technical field
The invention belongs to the industry wireless network communication technology, relate in particular to a kind of anti-interference method of industry wireless network.
Background technology
Along with the develop rapidly of wireless communication technology, technology such as 802.11b, ZigBee, bluetooth, IEEE 802.15.4 are applied to industry spot gradually.The introducing of these wireless communication technologys has solved problems such as industry spot difficult wiring, installation and maintenance cost height, but can't adapt to complicated industry spot environment, can not satisfy the demand of industry spot.IEEE 802.15.4 standard is as the PHY/MAC standard of a low-power consumption, low rate, the network of definition has energy-conservation characteristics, be suitable for industry wireless network, but do not consider the interference problem between the network channel, because industry spot adopts the network vulnerable of IEEE 802.15.4 standard to adopt the interference of IEEE 802.11b standard network, this has just reduced the antijamming capability of whole system.The main mode that the equipment of present IEEE 802.15.4 adopts for the interference of resisting IEEE 802.11b network is: adopt 1 in 3 channels (15,20,25) during communication.The present invention is proposing to increase self adaptation hop channel function on IEEE 802.15.4 mac-layer protocol under this background, anti-interference and the use blacklist technology of using special channel sequence (16 channels) to improve equipment shield disturbed channel, make it have the better resisting interference ability in industry spot.
Summary of the invention
The present invention is directed to and be subjected to the interference of outside noise easily in the industry spot data transmission procedure and decay, there is the phase mutual interference of channel between the different system, in order to reduce as far as possible or to eliminate these interference, ensure reliability of data transmission, propose to be fit to the self adaptation hop channel method of industry wireless network, effectively solve the safety issue of industry wireless network internal data communication, safeguards system is moved normally, when channel is interfered, can promptly shield disturbed channel and jump to the safe lane transceive data, make system not be subjected to the influence of external disturbance to continue operate as normal, and after channel is removed interference, cancel shielding.
The technical solution adopted in the present invention is: the channel that telegon is selected to be difficult in the network being disturbed by adjacent system equipment is as dedicated channel, with the dedicated channel is that boundary selects a channel to form the hop channel sequence from each channel group, make that any two adjacent channels do not belong to same coincidence zone in the hop channel sequence, the native system hop channel sequence that will generate according to dedicated channel is broadcast to the native system all devices as the essential information of network.In abutting connection with the channel operating position of network, judge whether ski-jump is used by the adjacency network around the telegon scanning, select the ski-jump of a ski-jump that is not used by the adjacency network as native system; In the load of beacon frame, add the hop channel information that comprises native system ski-jump and adjacent system ski-jump information; Telegon uses dedicated channel periodically to send beacon frame; Router and terminal equipment are resolved beacon frame, select the ski-jump of a untapped ski-jump as router and terminal equipment; Telegon and router regularly carry out channel estimating, determine the communication quality grade (good channel, difference channel, bad channel) of channel according to packet loss, when the communication quality grade was bad channel, this communication channel was disturbed channel, and disturbed channel is piped off.If communication channel is disturbed in the system, telegon pipes off this channel and shields disturbed channel, adopts next channel of disturbed channel to substitute the position of disturbed channel in the hop channel sequence.
Telegon and router are regularly assessed the channel in the blacklist, the packet loss that obtains by assessment is determined the communication quality grade of channel, when the communication quality grade of bad channel has reverted to channel or difference channel, from blacklist, delete this channel and recover its position in original hop channel sequence, be broadcast to the whole network all devices by telegon.
The present invention adds hop channel information according to IEEE 802.15.4 protocol stack in the load of beacon frame, by telegon the hop channel sequence is sent to each equipment in the mode of managing concentratedly.On the basis of IEEE802.15.4 protocol stack, realize functions such as channel replacement, the shielding of bad channel, channel recovery simultaneously, make between the industry wireless network system in same radio-frequency region and can effectively avoid radio frequency interference, thereby contained in the network influence of communicating by letter within the communication and native system between the different system, reach jamproof purpose, effectively improved the reliability and the fail safe of industry wireless network.Utilize the hop channel anti-interference method of this industry wireless network provided by the invention, can increase substantially coexistence performance, raising antijamming capability in the industry wireless network communication environment, and antijamming capability has determined directly fail safe, reliability and the compatibility etc. of industry wireless network system to be directly connected to every index of industry wireless network performance.Just because of the present invention research is the key technology of industry wireless network communication,, it plays huge impetus so using the standard formulation that advances industry wireless network and engineering.
Description of drawings
Fig. 1: mediators handle flow chart in the network
Fig. 2: hop channel information sends and receives process chart in the load of beacon frame
Fig. 3: channel estimating process chart
Fig. 4: the hop channel information structure diagram that adds in the load of beacon frame
Fig. 5: the channel distribution situation of IEEE 802.15.4 and IEEE 802.11b in the 2.4GHz frequency band
Fig. 6: the hop channel sequence produces schematic diagram
Fig. 7: the sequence after the 11# channel is disturbed is replaced figure
Fig. 8: a kind of hop channel combined sequence during i=1
Fig. 9: the replacement situation after a kind of hop channel combined sequence during i=1 is disturbed
Embodiment
The present invention is based on the interpolation of hop channel information in the industry wireless network communication protocol beacon frame load, the channel that telegon is selected to be difficult in the network being disturbed by adjacent system equipment is as dedicated channel, with the dedicated channel is that boundary selects a channel order to arrange generation hop channel sequence from each channel group, make any two adjacent channels not belong to same coincidence zone, generate above-mentioned native system hop channel sequence and native system hop channel sequence is broadcast to the native system all devices as the network essential information according to dedicated channel.In abutting connection with the channel operating position of network, scanning result has ski-jump that is used by the adjacency network and two kinds of situations of ski-jump of not used by the adjacency network around the telegon scanning, selects the ski-jump of a ski-jump conduct oneself of not used by the adjacency network; In the load of beacon frame, add the hop channel information that comprises native system ski-jump and adjacent system ski-jump information; Telegon uses dedicated channel periodically to send beacon frame; Router and terminal equipment are resolved beacon frame, confirm the ski-jump of parent device and the ski-jump that adjacent system uses, and select the ski-jump of the ski-jump of a free time as oneself, determine the current hop channel sequence of native system thus.Telegon and router dynamically scan all channels of present networks, detect the current communication quality of each channel by channel estimating, determine the communication quality grade of channel, classify according to the channel communication credit rating, bad channel is piped off, and, redefine ski-jump with the alternative position of bad channel in the hop channel sequence of the channel of the next position.Telegon and router are assessed the channel in the blacklist every some cycles, the packet loss that obtains by assessment is determined the communication quality grade (good channel, difference channel, bad channel) of channel, when the communication quality grade of bad channel has reverted to channel or difference channel, from blacklist, delete this channel and recover its position in original hop channel sequence, be broadcast to the whole network all devices by telegon.
Below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.
Be illustrated in figure 1 as mediators handle flow chart in the network of the present invention, telegon start around the scanning of back in abutting connection with the network channel operating position, the situation of scanning ski-jump, ski-jump that is used by the adjacency network and two kinds of situations of ski-jump of not used by the adjacency network are arranged, select the ski-jump of a ski-jump that is not used by the adjacency network as local network, the hop channel information that will comprise the ski-jump that uses in abutting connection with network ski-jump operating position and local network is packed into and is broadcasted as the part of beacon frame load in the load of beacon frame.Have data to send then to send data, when data send surpass maximum number of times of transmission do not send yet success then packet discard carry out channel estimating.There is blacklist information then to adjust the hop channel sequence in the data message that receives, redefines the local network ski-jump, substitute the position of disturbed channel, again blacklist is broadcast to the whole network with next channel of disturbed channel position in the hop channel sequence.
Being illustrated in figure 2 as in the load of beacon frame provided by the invention hop channel information sends and receives process chart, transmit leg sends the payload segment of up-to-date hop channel information (comprise the local network ski-jump and in abutting connection with the network ski-jump) beacon frame of packing into a part of load as beacon frame, the recipient resolves the up-to-date hop channel information of beacon frame acquisition after receiving beacon frame, check whether consistent with original hop channel information, if inconsistent then be revised as the hop channel information of just having received.Telegon and router carry out channel estimating after having data to send then to send data after sending beacon frame, but data send surpass maximum number of times of transmission do not send yet success then packet discard carry out channel estimating.
Be illustrated in figure 3 as channel estimating process chart provided by the invention, telegon and router regularly carry out channel estimating.According to the channel communication quality channel is divided three classes: good channel, difference channel and bad channel.Be set to above-mentioned three classes according to the packet loss channel that calculates, the packet loss of good channel is less than 2%; The packet loss of difference channel greater than 2% less than 5%; The packet loss of bad channel is more than or equal to 5%.Calculate packet loss by the computing unit in telegon or the router according to the quantity of sum that sends packet in the some cycles and lost data packets.
Packet loss=number of dropped packets/the sum of giving out a contract for a project
The sum of giving out a contract for a project: the packet sum that this equipment sent in some cycles (such as 1s);
Number of dropped packets: this equipment sending data bag is not but received the number of times that the other side confirms in some cycles (such as 1s), and promptly this equipment has sent packet but destination device is not received.
When telegon and router carry out channel estimating, at first add up give out a contract for a project sum and number of dropped packets in the nearest one-period, calculate packet loss then, according to the result of packet loss the communication quality grade of channel is set, packet loss has been set to channel less than 2%; Packet loss is set to difference channel greater than 2% less than 5%; Packet loss is more than or equal to 5% original communication quality grade of seeing channel, if being channel, original communication quality grade just is set to difference channel, just be set to bad channel and put into blacklist if original communication quality grade is a difference channel, channel with its next position in the hop channel sequence substitutes its position in the hop channel sequence, again blacklist is reported telegon step by step.
In hop channel mechanism of the present invention, the whole network uses same hop channel sequence, but according to the ski-jump difference, the hop channel sequence of reality that obtains each equipment thus is also different, router and terminal equipment obtain the essential information (comprising the hop channel sequence) of network by parent device when adding network, only need obtaining hop channel information from beacon frame, to determine that parent device and the ski-jump of oneself just can carry out the self adaptation hop channel with network anti-interference.
Be illustrated in figure 4 as the hop channel information structure diagram that beacon frame provided by the invention comprises, beacon frame is reserved three bytes at payload segment, is used for representing hop channel information specially.The hop channel sequence of the whole network transmission has only one, the sequences that 16 numerals of a 11-26 who is generated when forming network by telegon are formed, 11-26 represents the 11-26 channel of IEEE 802.15.4 on 2.4G respectively, each position in the sequence all can be used as ski-jump, can derive 16 different hop channel sequences thus.When ski-jump was 1, promptly first position from sequence began to carry out hop channel toward the afterbody of sequence; When ski-jump was 2, promptly last position from sequence began to carry out hop channel, was first of sequence afterwards; When ski-jump was 3, promptly the afterbody from the 15th beginning of sequence toward sequence carried out hop channel; By that analogy, when ski-jump was 16, promptly second position from sequence began to carry out hop channel toward the afterbody of sequence.The preceding four bit representation present networks take-off point values of hop channel information, the corresponding employed hop channel sequence of each take-off point value; Back two byte representations are in abutting connection with the situation of network use ski-jump, and 1-16 represents 16 ski-jump positions in the hop channel sequence respectively, and its value is set to 1 expression and has used this ski-jump in abutting connection with network, are that 0 this ski-jump of expression is not used by the adjacency network.
Below be example with the Channel Transmission of IEEE 802.15.4 and IEEE 802.11b, adopt the hop channel Anti-Jamming Technique to be specifically described to the present invention.
Be illustrated in figure 5 as provided by the invention in the 2.4GHz frequency band, follow the network and the channel distribution situation of following the network of IEEE 802.11b agreement of IEEE 802.15.4 agreement, IEEE 802.15.4 is at the 5MHz that is spaced apart of each interchannel of 2.4GHz, the centre frequency of 11# channel is 2405MHz, the centre frequency of 12# channel is 2410MHz, by that analogy, the centre frequency of 26# channel is 2480MHz.The bandwidth of IEEE802.11b is 22 MHz, the centre frequency of I# channel is at 2412MHz, the centre frequency of VI# channel is at 2437MHz, the centre frequency of XI# channel is at 2462MHz, therefore, the I# channel of IEEE 802.11b overlaps with 11#, the 12# of IEEE 802.15.4,13#, 14# channel, the VI# channel of IEEE 802.11b overlaps with 16#, the 17# of IEEE 802.15.4,18#, 19# channel, and the XI# channel of IEEE 802.11b overlaps with 21#, the 22# of IEEE 802.15.4,23#, 24# channel.Have two kinds of systems in same network, and two kinds of systems are when working simultaneously, the above-mentioned interchannel that coincides disturbs easily.
In fact, the transmitting power of IEEE 802.11b is 30 times of IEEE 802.15.4, for avoiding interference, IEEE 802.15.4 is in 16 channels of 2.4GHz, select IEEE 802.15.4 to be in the I# channel of 802.11b and the 15# channel of VI# interchannel, be in the 20# channel of the VI# channel of 802.11b and XI# interchannel and 25# channel and 26# channel as dedicated channel, can avoid the working band of 802.11b.
Dedicated channel (15#, 20#, 25#, 26#) be used for broadcast beacon frame, the bigger equipment in the IEEE802.11b system does not disturb by power when sending beacon frame for the telegon in IEEE 802.15.4 system and router, selects 15#, 20#, 25#, these four channels that do not overlap with the working channel of IEEE 802.11b of 26# are as dedicated channel.
Being illustrated in figure 6 as hop channel sequence provided by the invention and producing schematic diagram, is boundary with the dedicated channel, with 16 channels in the IEEE 802.15.4 system be divided into four channel group: 11#, 12#, 13#, the 14# channel is one group; 16#, 17#, 18#, 19# channel are one group; 21#, 22#, 23#, 24# channel are one group; Last 26# channel is as one group.
From each channel group, select a channel to form the hop channel sequence, make any two adjacent channels not belong to same coincidence zone, the selection step is as follows: first channel order of choosing successively in every group is formed one group of hop channel sequence, and second channel order choosing every group formed one group of hop channel sequence, such direct election is gone down, channel in all channel group has all been selected, and at last three dedicated channel 15#, 20#, 25# channel is put into successively the last of hop channel sequence.From the hop channel sequence that chooses as can be seen, any two adjacent channels do not belong to same coincidence zone.So, when replacing current channel, can guarantee to replace channel and not belong to same disturbed area territory with an adjacent back channel.Select the benefit of sequence also to have following two advantages like this:
1. the above bandwidth of 20MHz of being separated by between the assurance adjacent channel
2. guarantee that adjacent two resident cycles do not rest on same group and overlap the zone
In 16 hop channel sequences that all obtain, choose different ski-jump (n), the position of each channel in sequence is all different, be that resulting hop channel sequence is all mutually orthogonal, these 16 mutually orthogonal sequences are distributed to heterogeneous networks in the mutual interference scope on demand, can guarantee that the heterogeneous networks in the radio-frequency region is in different channels constantly, be phase mutual interference between the system thereby avoid channel confliction.
Lift an instantiation below and illustrate how certain channel replaces disturbed channel with other hop channel sequences after disturbed.
Be illustrated in figure 7 as the hop channel sequence replacement figure of 11# channel after disturbed.If the 11# channel is disturbed, substitute the principle of current disturbed channel according to back one channel, replace the 11# channel with the 16# channel, and the 11# channel piped off and report blacklist step by step until telegon, telegon is with blacklist information notice the whole network all devices, after whole network equipment is received blacklist, also substitute the principle of current disturbed channel, replace the 11# channel with the 16# channel by back one channel.
A kind of hop channel combined sequence when being illustrated in figure 8 as i=1 provided by the invention.Telegon or router are selected definite at interval ski-jump in abutting connection with network according to hop channel sequence ski-jump.I is that hop channel sequence ski-jump is selected at interval, hop channel sequence ski-jump is set selects at interval, when interval that telegon or router are selected not simultaneously, the selected ski-jump of equipment has different combining forms.Represent during i=1 to select to be spaced apart one in abutting connection with the ski-jump of network, can only choose ski-jump is 1,3,5,7,9 Represent during i=2 to select to be spaced apart two in abutting connection with the ski-jump of network, can only choose ski-jump is 1,4,7,10 Represent during i=3 to select to be spaced apart three in abutting connection with the ski-jump of network, can only choose ski-jump is 1,5,9,13 ...Any channel does not all occur twice at any row, does not promptly have two same channels of hold facility at synchronization.
Replacement situation after a kind of hop channel combined sequence when as shown in Figure 9, Fig. 9 is i=1 provided by the invention is disturbed.When industry wireless network system during by IEEE 802.11b system interference, obviously, the industry wireless network system can be disturbed to continuous 4 channels.Just communicate if any an IEEE 802.11b equipment, so, will inevitably disturb associated continuous 4 channels of IEEE802.15.4 by its I# channel or VI# channel or XI# channel.At this moment, we replace these disturbed 4 channels one by one with a back channel of disturbed channel in the hop channel sequence, replace the interference that channel is not subjected to the current communication equipment of IEEE802.11b for 4.Suppose that the industry wireless network system is subjected to the interference of the IEEE 802.11b I# of system channel (11#, the 12#, 13#, the 14# channel that are equivalent to IEEE802.15.4 all are interfered), substitute the principle of current disturbed channel according to back one channel, adopt a back channel of disturbed channel to replace current disturbed channel, replace any channel in back and all do not occur twice, promptly do not have two same channels of hold facility at synchronization at any row.
Above-described specific embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of being made, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (6)
1. method for channel hopping and RF interference resisting in the industry wireless network, it is characterized in that, the channel that telegon is selected to be difficult in the network being disturbed by adjacent system equipment generates native system hop channel sequence and is broadcasted to the native system all devices according to dedicated channel as dedicated channel; In the load of beacon frame, add the hop channel information that comprises native system ski-jump and adjacent system ski-jump; Telegon uses dedicated channel periodically to send beacon frame; Router and terminal equipment are resolved beacon frame, select the current ski-jump of a untapped ski-jump as router and terminal equipment; If communication channel is disturbed in the system, telegon shields disturbed channel, and employing next channel of disturbed channel in the hop channel sequence is replaced disturbed channel, redefines the new ski-jump of router and terminal equipment.
2. radio frequency interference resistant method according to claim 1, it is characterized in that, the method of described generation hop channel sequence specifically comprises, with the dedicated channel is boundary, 16 channels in the IEEE 802.15.4 system are divided into four channel group, from each channel group, select a channel to form the hop channel sequence successively, make any two adjacent channels not belong to same coincidence zone.
3. radio frequency interference resistant method according to claim 1, it is characterized in that telegon and router regularly carry out channel estimating, determine the communication quality grade of channel according to packet loss, when the communication quality grade was bad channel, this communication channel was disturbed channel.
4. radio frequency interference resistant method according to claim 1 is characterized in that, chooses different ski-jumps in all hop channel sequences, and resulting hop channel sequence is all mutually orthogonal.
5. radio frequency interference resistant method according to claim 1 is characterized in that the payload segment of beacon frame comprises hop channel information, and the hop channel sequence of the whole network transmission has only one.
6. radio frequency interference resistant method according to claim 1 is characterized in that, telegon or router are selected definite at interval ski-jump in abutting connection with network according to hop channel sequence ski-jump.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102075211A (en) * | 2010-11-29 | 2011-05-25 | 中国有色（沈阳）冶金机械有限公司 | Wireless Ethernet transmission system for electrolysis unit and data exchange method thereof |
| CN102036286B (en) * | 2010-12-31 | 2013-03-20 | 重庆邮电大学 | Deterministic scheduling-based wireless sensor network channel assessment method |
| CN102088741B (en) * | 2011-03-02 | 2013-01-09 | 上海交通大学 | Method for coping with malicious interference in wireless sensor network (WSN) |
| CN102209329B (en) * | 2011-05-17 | 2013-12-25 | 深圳国威电子有限公司 | Multi-base-station anti-jamming method based on cordless telephone system |
| CN102655686B (en) * | 2012-05-08 | 2015-01-07 | 华为技术有限公司 | Frequency spectrum spreading method and device of wireless local area network (WLAN) |
| EP3035741A1 (en) | 2014-12-17 | 2016-06-22 | Thomson Licensing | WLAN user quality of experience control in a multi-access point environment |
| CN105812024B (en) * | 2014-12-30 | 2018-06-08 | 上海科勒电子科技有限公司 | A kind of wireless communication frequency-hopping method |
| US10594360B2 (en) * | 2015-05-22 | 2020-03-17 | Texas Instruments Incorporated | Enhanced channel hopping sequence |
| CN107547112B (en) * | 2017-07-20 | 2021-08-20 | 海信视像科技股份有限公司 | Method, device and system for recovering channel between master device and slave device |
| CN108957430A (en) * | 2018-05-08 | 2018-12-07 | 重庆邮电大学 | Radiofrequency Interference in High Frequency Radar method for extracting region based on distance-Doppler figure |
| WO2021028153A1 (en) | 2019-08-09 | 2021-02-18 | Signify Holding B.V. | Interference suppressing for optical wireless networks |
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| CN1207218A (en) * | 1996-11-13 | 1999-02-03 | 诺基亚电信公司 | Frequency hopping method and radio system |
| CN1860695A (en) * | 2003-09-10 | 2006-11-08 | 艾利森电话股份有限公司 | Detection of process state change |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1207218A (en) * | 1996-11-13 | 1999-02-03 | 诺基亚电信公司 | Frequency hopping method and radio system |
| CN1860695A (en) * | 2003-09-10 | 2006-11-08 | 艾利森电话股份有限公司 | Detection of process state change |
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