CN101325461B - Method for establishing and maintaining cognition radio communication link based on non-speed code - Google Patents
Method for establishing and maintaining cognition radio communication link based on non-speed code Download PDFInfo
- Publication number
- CN101325461B CN101325461B CN2008100637103A CN200810063710A CN101325461B CN 101325461 B CN101325461 B CN 101325461B CN 2008100637103 A CN2008100637103 A CN 2008100637103A CN 200810063710 A CN200810063710 A CN 200810063710A CN 101325461 B CN101325461 B CN 101325461B
- Authority
- CN
- China
- Prior art keywords
- spectrum resource
- transmitting terminal
- receiving terminal
- frequency spectrum
- cognitive user
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Mobile Radio Communication Systems (AREA)
Abstract
The invention discloses a building method for perceiving the radio communication chain based on the speed free code and a maintaining method, comprising: perceiving the building method of the chain of the user transmitting end, perceiving maintaining method of the chain of the user transmitting end, and perceiving the building method of the chain of the user receiving end and the maintaining method of the chain of the user receiving end. According to the characteristics of the speed free code which can deal with the deletion of the chain and the lost of the data pack adaptively, the building and the maintenance of the communication chain are processed, and the required feedback of the speed free code is used to respond the time slot, therefore, the 'spectrogram exchange' at the extra common control channel between the main user and the slave user is not required by the method.
Description
Technical field
The present invention relates to wireless communication field, be specifically related in cognitive radio system, the cognitive user transmitting-receiving two-end is communicated the method that link initialization is set up and communication link is safeguarded.
Background technology
The frequency spectrum share radio communication is the inexorable trend and the requirement of following wireless communication technology development.It can make a plurality of isomeries, having different systems or belong to the communication system of different operators can be dynamically and the same shared band of chance formula accessing, realize frequency spectrum authorized user and/or unauthorized user reliably, coexistence harmoniously, thereby effectively solve the deficient day by day pressing issues of available radio spectrum resource, significantly improve the utilization ratio of existing frequency spectrum resource simultaneously.Cognitive radio system is exactly a kind of technological means that realizes the frequency spectrum share radio communication.
Cognitive radio system is a kind of smart frequency spectrum technology of sharing, and it can pass through perceived spectral environment, intelligence learning and adjust its transmission parameter in real time, realizes the utilization again of frequency spectrum, improves the availability of frequency spectrum.In cognitive radio technology, the designated user system (also claiming main user, Primary User) that obtains the frequency spectrum mandate in advance has high priority and inserts frequency spectrum; And other not authorized custom system (also claiming time user, Secondary User) can only communicate by chance formula access usable spectrum under the situation that main user is not caused interference.This just requires time user oneself or possess certain " cognitive ability " under the help of other user (for example some relaying is transmitted the user), promptly can real-time continuous intercept frequency spectrum, to find available " frequency spectrum hole " (the unappropriated frequency spectrum of promptly main user).The user's (can be time user, also can be that some relaying is transmitted the user) who possesses cognitive ability is called " cognitive user ".Say that in essence cognitive radio system is exactly in order to realize the adaptive communications in the environment interference-limited under multi radio (Multi-Radio) electromagnetic environment.
Outstanding characteristics of cognitive radio are, employed frequency of its link and bandwidth are not to pre-determine or changeless.Owing to do not have available frequencies in advance, so its link must be set up dynamically.And, owing to there is the influence of factors such as multipath and shadow fading in the wireless communication system, the detectability itself that adds cognitive user has certain restriction, the cognitive user transmitting-receiving two-end comprises disturbance state information and incomplete same by the resulting channel condition information of frequency spectrum perception, may detect not quite identical usable frequency and bandwidth thus, thereby cause the foundation of communication link relatively more difficult usually.Fig. 1 represents is the transmitting terminal of cognitive user and the receiving terminal schematic diagram to the frequency spectrum perception situation.Supposing the system has 5 frequency spectrum resources, respectively it is carried out label with numeral.Suppose that user's transmitting terminal detects No. 1 and No. 3 frequency spectrum resources are occupied, the usable spectrum resource is No. 0, No. 2 and No. 4; And user's receiving terminal detects No. 2 and No. 3 frequency spectrum resources are occupied, and the usable spectrum resource is No. 0, No. 1 and No. 4.
Therefore, because the receiving-transmitting sides channel condition information not exclusively is correlated with and is uncertain of mutually, if will between the transmitting-receiving two-end of cognitive user, set up and the maintain communications link, transmitting-receiving two-end has only by suitable " spectrogram exchange (Spectrum Exchange) " learns that the opposite end is not only the interference profile of self-position, just can finish the link setup process and begin effective transmission.If adopt the method for direct perception or estimation opposite end frequency spectrum resource, not only the process complexity also might be introduced extra dynamic disturbance.Therefore, do not know that at transmitting terminal channel accurately under the state information situation, the reliable effectively transmission of guarantee information, often need ARQ (repeat requests automatically).Conventional method cognitive user transmitting terminal generally adopts the chnnel coding of cbr (constant bit rate) that transmission information is protected; but because the employed frequency spectrum resource of cognitive user at any time all may be by main CU; therefore the transmission channel of cognitive user is not protected; can't determine the drop probabilities of channel, promptly the instant capacity of channel is not changeless.In case frequency spectrum suffers that main user causes the code check of channel capacity less than transmission, receiving terminal just can't guarantee correct decoding, thereby causes communication failure.At this moment, need receiving terminal to send feedback information and inform that transmitting terminal adjustment emission parameter carries out coding transmission again.Owing to adopt different coded systems, thereby so the coding that receives before the receiving terminal often can't carry out the encoded packets of joint decoding before having caused and almost can't be utilized and be dropped with adjusted coding, thereby caused the waste of information.If adopt the chnnel coding of very low code check to guarantee the reliability of transmitting as far as possible, then can cause the waste of channel equally because having transmitted too much redundant information, even adopt a low code check, can't guarantee that also this code check necessarily can reliable transmission in cognitive radio system.In addition, the somebody proposes to be provided with the method that a Common Control Channel is used for transmitting frequency spectrum perception situation between cognitive user and feedback information, and supposes that the frequency spectrum of this Common Control Channel is not disturbed by main user.Though this method can guarantee the reliable transmission of signal, it requires main user can not take the frequency spectrum of Common Control Channel, the principle that this activity of having run counter to cognitive user in the cognitive radio system itself should not impact main user.And only adopt a characteristic frequency to transmit, and its communication certainly will will adopt the mode of time-division to finish, and efficient can be too not high yet.
Therefore how the suitable code check of adaptive selection transmits, and is the crucial difficult problem that the cognition radio communication link is faced to adapt to different channel parameters.The adaptation rate of no-rate codes (rateless code) adaptive (Rate Adaption) ability provides a kind of new approaches for head it off, this mainspring of the present invention just.
No-rate codes and conventional fixed bit rate coding mode maximum different are that it does not set cbr (constant bit rate) at transmitting terminal, and transmitting terminal can produce encoded packets in some way endlessly and send.Receiving terminal then can be according to the encoded packets trial and error decoding that receives, and need not all encoded packets are all received.If decoding failure, receiving terminal can again receive some encoded packets more and continue trial and error decoding then.Whichever wraps in disturbed abandoning in the transmittance process, and the final bag that only need obtain some of receiving terminal just can be finished decoding, and this quantity is linear with the packet that will send.Receiving terminal will repeat this process up to successfully decoded always.At this moment receiving terminal only need send a very simple feedback signal and inform that transmitting terminal is successfully decoded, and transmitting terminal stops to send then, has so just finished whole transmission course.
Utilize no-rate codes can tackle the characteristic of channel deletion admirably, when transmitting-receiving two-end under the frequency spectrum share wireless communications environment and not exclusively know the other side's channel status and cause when sending packet loss or being subjected to main subscriber signal interference owing to frequency spectrum perception is not accurate enough, no-rate codes can send encoded packets continuously on different time or frequency, and as long as receiving terminal can receive abundant encoded packets on part-time and frequency, restore data correctly, thus the foundation of link finished.And, utilize no rate coding technology can make full use of diversity gain between a plurality of frequency spectrum resources, the more important thing is that thereby can make full use of the characteristic that no-rate codes can approach cognitive channel capacity adaptively obtains huge coding gain, this be traditional utilize the fixed rate Methods for Coding can't obtain.
Summary of the invention
The purpose of this invention is to provide a kind ofly in cognitive radio system, need not to utilize under the condition of Common Control Channel, utilize no-rate codes to set up reliably, efficiently and the method for maintain communications link at the cognitive user transmitting-receiving two-end.
The foundation and the maintaining method of the cognition radio communication link based on no-rate codes of the present invention, it is characterized in that comprising the method for building up of cognitive user transmitting terminal link and maintaining method and the method for building up of cognitive user receiving terminal link and the maintaining method of cognitive user receiving terminal link of cognitive user transmitting terminal link, the feedback of the type one of the following stated represents that receiving terminal has successfully received data, the feedback of type two represents that receiving terminal has detected main user and need take the frequency spectrum resource that is utilizing, the feedback of type three represents that receiving terminal thinks that this frequency spectrum resource can use, and the feedback of type four represents that receiving terminal confirms to detect new available spectrum resource jointly with transmitting terminal;
If: whole frequency spectrum resources has n in the whole cognitive system, uses label f=[f respectively
1, f
2..., f
n] come mark, when a certain cognitive user inserts, there are not other cognitive user to insert at identical time slot,
The method for building up of cognitive user transmitting terminal link may further comprise the steps:
1) transmitting terminal carries out perception to whole n frequency spectrum resources in the whole cognitive system, and it is idle available obtaining which frequency spectrum resource, establishes and detects p usable spectrum resource, and it is designated as
And 0≤p≤n; The detection usable spectrum resource that transmitting terminal is real-time when finding that the usable spectrum resource changes, is upgraded f in real time
t
2) if usable spectrum resource f
tBe empty set, promptly current all frequency spectrum resources are all occupied, then change step 1) perception again over to; If usable spectrum resource f
tNot empty set, then change step 3) over to;
3) with user's initialization system information m of cognitive user
sCoded system according to no-rate codes is encoded and framing to packets of information; Use t
iThe presentation code frame, wherein i is the numbering of coded frame, i=0,1,2,
4) transmitting terminal is with each coded frame and the current usable spectrum resource f that perceives
tIn the usable spectrum resource do the emission that correspondence is carried out coded frame, each frequency spectrum resource is all regarded a subchannel as; Concrete mapping ruler is: if imodp=k, and k ≠ 0, then coded frame is just with the
Individual subchannel sends; If imodp=0, then coded frame is just with the
Individual subchannel sends;
5) transmitting terminal produces coded frame endlessly according to the coding rule of no-rate codes and informs that up to receiving terminal it stops to send, simultaneously at current usable spectrum resource f
tOn reply the feedback signal of intercepting receiving terminal in the time slot, then change step 6) over to if listen to the feedback signal of type one; Otherwise, the process of continuation step 5);
6) transmitting terminal stops to continue to produce coded frame and stopping emission immediately, then at all current usable spectrum resource f
tOn reply the feedback signal of intercepting receiving terminal in the time slot, and all frequency spectrum resources that can receive the feedback signal of type three are noted down separately, be designated as f
c, f
cIn all frequency spectrum resources be exactly cognitive user transmitting terminal and receiving terminal the usable spectrum resource of common approval, thereby finished the foundation of cognitive user transmitting terminal link;
The maintaining method of cognitive user transmitting terminal link may further comprise the steps:
1) after communication link is set up, on one side transmitting terminal utilizes f
cIn frequency spectrum resource information that oneself need is sent according to the coded system of no-rate codes packets of information is encoded and framing, emission then, the real-time whole frequency spectrum resources in the whole cognitive system carry out perception on one side, and wait for the feedback signal of receiving terminal in " replying time slot "; Need take the frequency spectrum that carries out data passes if the main user of discovery comes into play, then change step 2 over to); If receive the feedback signal of cognitive user, then change step 3) over to; If perceive new usable spectrum resource, then change step 5) over to;
2) the main user that perception the is obtained frequency spectrum resource that need take completely discharges no longer and holds over, and utilizes all the other usable spectrum resources to continue to transmit the Frame that will send;
3) confirm to receive the feedback signal of cognitive user after, the type of differentiating feedback signal immediately is type one or type two, if type one illustrate that data passes finishes, then transmitting terminal stops transmission, if type two then changes step 4) over to;
4) feedback of differentiating type two by which frequency spectrum receives, and stops at immediately on these frequency spectrums and continue Data transmission, only utilizes all the other available spectrum resources, and all the other available spectrum resource updates are designated as f
c, change step 1) over to;
5) transmitting terminal is attempting receiving in " replying time slot " on the frequency spectrum resource that newly perceives the feedback of receiving terminal, if confirm to receive the feedback of receiving terminal on this frequency spectrum, then changes step 6) over to; If find that before receiving feedback signal this frequency spectrum again by main CU, then stops at the activity on this frequency spectrum, change step 1) over to;
That 6) confirms receiving terminal is fed back to feedback kind three, then sends confirmation on these frequency spectrums, waits for the further feedback of receiving terminal; If obtain the feedback of the type four of receiving terminal, then this frequency spectrum charged to f
c, change step 1) over to, otherwise do not upgrade f
c, change step 1) over to;
The method for building up of cognitive user receiving terminal link may further comprise the steps:
1) receiving terminal carries out perception to whole n frequency spectrum resources in the whole cognitive system, and it is idle available obtaining which frequency spectrum resource, establishes and detects q usable spectrum resource, and it is designated as
And 0≤q≤n; The detection usable spectrum resource that receiving terminal is real-time when finding that the usable spectrum resource changes, is upgraded f in real time
r
2) receiving terminal is being attempted at f
rIn all frequency spectrums on carry out message pick-up, the frequency spectrum perception that need not to know transmitting terminal is f as a result
t, at this moment, as long as f
tWith f
rCommon factor be not empty, then receiving terminal always can receive the coded message of transmitting terminal certainly on it occurs simultaneously frequency spectrum resource;
3) when the coded frame quantity that receives reaches the quantity of coded frame of user's beacon information of transmitting terminal, begin to decipher, and utilize Cyclic Redundancy Check to judge whether that decoding is correct, if correct, changes step 6) over to; Otherwise change step 4) over to;
4) continue to receive several encoded packets;
5) if trial and error decoding again successfully decoded, changes step 6) over to; Otherwise change step 4) over to;
6) decoding finishes, but receiving terminal is designated as f with the frequency spectrum resource of all received code frames
c, f
cBe the set of the usable spectrum resource that transmitting terminal and receiving terminal perceived jointly, and at f
cThe feedback signal of replying transmission types one on the time slot of intermediate frequency spectrum resource;
7) if receiving terminal is not all received the coded frame of transmitting terminal in continuous 3 time slots next, then at f
cIn all frequency spectrum resource reply the feedback signal that sends twice type one on the time slot, be used for notifying transmitting terminal;
8) the transmitting terminal initialization system information m that obtains according to decoding success of receiving terminal
s, learn the requirement of transmitting terminal, thereby finished the foundation of cognitive user receiving terminal link;
The maintaining method of cognitive user receiving terminal link may further comprise the steps:
1) after communication link is set up, on one side receiving terminal utilizes f
cIn frequency spectrum resource receive the Frame that transmitting terminal transmits, on one side real-time whole frequency spectrum resources in the whole cognitive system carry out perception, if successfully decoded during this period, recover the full detail data that transmitting terminal will send, then change step 2 over to); If perception is found that main user comes into play and need be taken the frequency spectrum that carries out data passes, then change step 3) over to; If perceive new usable spectrum resource, then change step 4) over to;
2) receiving terminal all f in " replying time slot "
cThe feedback of transmission types one on the frequency spectrum resource of mark is informed that transmitting terminal stops to send data immediately, thereby is finished the transmission of whole data;
3) the main user that perception the is obtained frequency spectrum resource that need take is labeled as f
z, and the feedback of " replying in the time slot " transmission types two on these frequency spectrums, and with f
zThe frequency spectrum resource of middle mark is at f
cIn shift out, change step 1) over to;
4) in " replying time slot " of perceiving new usable spectrum resource, send the feedback of several times type three to transmitting terminal, and on these frequency spectrums, attempt to receive the affirmation signal of transmitting terminal, if receive the affirmation signal of transmitting terminal, then the feedback of transmission types four is done further affirmation again, and the usable spectrum resource that these are new is incorporated f into
c, change step 1) over to; If do not receive, then change step 1) over to.
Among the present invention, the coded system according to no-rate codes in the method for building up of cognitive user transmitting terminal link is encoded and framing to packets of information, and its step is as follows:
1), establishes the information m that will transmit according to initialization system information
sLength be L1, m1 is divided into
Individual small data packets, each small data packets length is k1, if L1 can't be divided exactly k1, then the long part of the not enough k1 of last small data packets is filled with " 0 ";
2) utilize cyclic redundancy check (CRC) code to carry out cyclic redundancy check (CRC) to the long small data packets of each k1, each small data packets length is increased to the k1+r1 bit accordingly according to the length r1 of the cyclic redundancy check (CRC) code that adopts;
3) will
Individual length is that the encoder that the small data packets of k1+r1 bit is sent into no-rate codes is encoded, and according to the generation order of encoded packets these encoded packets is designated as C=[c
0, c
1, c
2... ], the subscript of each encoded packets is represented this encoded packets residing position in the middle of entire coded sequence, utilizes g bit to come the subscript of presentation code bag;
4) the linear block codes encoder of the subscript of each encoded packets being sent into one 1/4 code check is encoded, generation length be the data of g * 4 bits as location mark, and location mark is placed on after each encoded packets;
5) adding length before each encoded packets is that 64 * 4 targeting sequencing is used for realizing bit synchronization and channel estimating, and adds the interval of 64 bits after each encoded packets, as " replying time slot ";
6) after targeting sequencing, also will add the initialization preamble sequence that length is 64 * 4 bits before the digital coding bag, the preamble sequence content comprises the customer identification number of transmitter and target receiver, be used for User Recognition and the auxiliary bit synchronization that realizes, finish coding and framing.
Among the present invention, the coded system according to no-rate codes in the maintaining method of cognitive user transmitting terminal link is encoded and framing to packets of information, and its step is as follows:
1) establishing the information that will transmit is m, and length is L2, and m is divided into
Individual small data packets, each small data packets length is k2, if L2 can't be divided exactly k2, then the long part of the not enough k2 of last small data packets is filled with " 0 ";
2) utilize cyclic redundancy check (CRC) code to carry out cyclic redundancy check (CRC) to the long small data packets of each k2, each small data packets length is increased to the k2+r2 bit accordingly according to the length r2 of the cyclic redundancy check (CRC) code that adopts;
3) will
Individual length is that the encoder that the small data packets of k2+r2 bit is sent into no-rate codes is encoded, and according to the generation order of encoded packets these encoded packets is designated as C=[c
0, c
1, c
2... ], the subscript of each encoded packets is represented this encoded packets residing position in the middle of entire coded sequence, utilizes g bit to come the subscript of presentation code bag;
4) linear block codes of the subscript of each encoded packets being sent into one 1/4 code check is encoded, generation length be the data of g * 4 bits as location mark, and location mark is placed on after each encoded packets;
5) adding length before each encoded packets is that 64 * 4 targeting sequencing is used for realizing bit synchronization and channel estimating, and adds the interval of 64 bits after each encoded packets, as " replying time slot ", finishes coding and framing.
Advantage of the present invention:
Basic fundamental thought of the present invention is foundation and the maintenance that the characteristic of utilizing no-rate codes can adaptively tackle link circuit deleting and data-bag lost communicates link, and make full use of the required feedback of no-rate codes and reply time slot, thereby do not need to exist between the principal and subordinate user extra Common Control Channel to carry out " spectrogram exchange ".
Description of drawings
Fig. 1 is the transmitting terminal of cognitive user and the receiving terminal schematic diagram to the frequency spectrum perception situation;
Fig. 2 is the method for work flow chart of transmitting terminal when setting up communication link of cognitive user;
Fig. 3 is the structural representation of a coded frame in the link establishment process;
Fig. 4 is the method for work flow chart of transmitting terminal when the maintain communications link of cognitive user;
Fig. 5 is the structural representation of a coded frame in the link maintenance process;
Fig. 6 is the method for work flow chart of receiving terminal when setting up communication link of cognitive user;
Fig. 7 is the method for work flow chart of receiving terminal when the maintain communications link of cognitive user;
Embodiment
Further specify the present invention below in conjunction with accompanying drawing.
The foundation and the maintaining method of the cognition radio communication link based on no-rate codes of the present invention, comprise the method for building up of cognitive user transmitting terminal link and maintaining method and the method for building up of cognitive user receiving terminal link and the maintaining method of cognitive user receiving terminal link of cognitive user transmitting terminal link, the feedback of the type one of the following stated represents that receiving terminal has successfully received data, the feedback of type two represents that receiving terminal has detected main user and need take the frequency spectrum resource that is utilizing, the feedback of type three represents that receiving terminal thinks that this frequency spectrum resource can use, and the feedback of type four represents that receiving terminal confirms to detect new available spectrum resource jointly with transmitting terminal;
If: whole frequency spectrum resources has 256 in the whole cognitive system, and all 256 frequency spectrums carry out ascending label from low to high according to its frequency, be designated as respectively [0,1 ..., 255].Each user in the cognitive radio system distributes the sign of the proprietary user number of a b bit length as user identity, for example if b=16 then can support 65536 users in theory at most.Before communication link is not set up as yet, the transmitting-receiving two-end of cognitive user is all known nothing the information of necessity such as the other side's frequency spectrum perception situation and the chnnel coding that will adopt, modulation mapping mode, must the information that these are necessary pass to the other side in the process of communication link foundation.These information are called " initialization system information ", are designated as m
sWhen a certain cognitive user inserts, there are not other cognitive user to insert at identical time slot.
The method for building up (referring to Fig. 2) of cognitive user transmitting terminal link may further comprise the steps:
1) transmitting terminal to whole 256 frequency spectrum resources in the whole cognitive system real-time carry out perception, obtain the cognitive result of transmitting terminal to the entire spectrum resource, promptly which frequency spectrum resource is idle available under the current time.Suppose that cognitive transmitting terminal obtains p available spectrum resource by detection, and these available spectrum resource labels are carried out record, be designated as
0≤p≤256; Real-time 256 frequency spectrum resources to whole of transmitting terminal carry out perception, when finding that the usable spectrum resource changes, then upgrade f in real time
t
2) if usable spectrum resource f
tBe empty set, promptly current all frequency spectrum resources are all occupied, then change step 1) perception again over to; If usable spectrum resource f
tNot empty set, then change step 3) over to;
3) with initialization system information m
sCoded system according to no-rate codes is encoded and framing to packets of information, and the frame structure of being formed is (concrete steps are introduced below) as shown in Figure 3; Use t
iThe presentation code frame, wherein i is the numbering of coded frame, i=0,1,2,
4) transmitting terminal current usable spectrum resource f that each coded frame and perception are obtained
tIn the usable spectrum resource do correspondingly to carry out the emission of coded frame, each frequency spectrum resource is all regarded a subchannel as; Concrete mapping ruler is: if imodp=k, and k ≠ 0, then encoded packets is just with the
Individual subchannel sends; If imodp=0, then encoded packets is just with the
Individual subchannel sends;
5) transmitting terminal produces coded frame endlessly according to the coding rule of certain no-rate codes (for example Raptor Code) and launches, simultaneously at current usable spectrum resource f
tOn reply the feedback signal of intercepting receiving terminal in the time slot, then change step 6) over to if listen to the feedback signal of type one; Otherwise, the process of continuation step 5);
6) transmitting terminal stops to continue to produce coded frame and stopping emission immediately, then at all current usable spectrum resource f
tOn reply the feedback signal of intercepting receiving terminal in the time slot, and all frequency spectrum resources that can receive the feedback signal of type three are noted down separately, be designated as f
c, f
cIn all frequency spectrum resources be exactly cognitive user transmitting terminal and receiving terminal the usable spectrum resource of common approval, thereby finished the foundation of cognitive user transmitting terminal link;
Above-mentioned with initialization system information m
sCoded system according to no-rate codes is encoded and framing to packets of information, establishes the information m that will transmit
sLength be L1, as follows to information m
sHandle:
1) with m
sBe divided into several little packets, each packet length is the k1 bit, if L1 can't be divided exactly k1, then the long part of the not enough k1 of last small data packets is filled with " 0 ", so just is partitioned into
Individual length is the small data packets of k1;
2) the long small data packets of each k1 is all carried out cyclic redundancy check (CRC), be used for decoder and judge whether decoding is successful, and cyclic redundancy check (CRC) code adopts CRC16 in this example, and each small data packets length is the k1+16 bit like this;
3) with this
Individual length is that the encoder that the small data packets of k1+16 bit is sent into certain no-rate codes (for example Raptor Code) is encoded, produce the encoded packets C that length is all the k1+16 bit endlessly, these encoded packets are designated as C=[c according to the generation of encoded packets order
0, c
1, c
2... ], the subscript of each encoded packets is represented this encoded packets residing position in the middle of entire coded sequence, utilizes 16 bits to come the subscript of presentation code bag, then can support 2
16Long encoded packets;
4) the linear block codes encoder of target 16 bit informations under each presentation code bag being sent into one 1/4 code check carries out coding protection, promptly utilize 64 bits to come the positional information of presentation code bag, and the encoded packets positional information of this 64 bit is placed on after each encoded packets;
5) adding length before each encoded packets is that 64 * 4 targeting sequencing is used for realizing bit synchronization and channel estimating, and adds the interval protection of 64 bits after each encoded packets, and protection also can be used as " replying time slot " simultaneously at interval;
6) after targeting sequencing, also will add the initialization preamble sequence that length is 64 * 4 bits before the digital coding bag, its content comprises the customer identification number of transmitter and target receiver, be used for User Recognition and the auxiliary bit synchronization that realizes, the frame structure of being formed as shown in Figure 3.
The maintaining method (referring to Fig. 4) of cognitive user transmitting terminal link may further comprise the steps:
1) after communication link is set up, on one side transmitting terminal utilizes f
cIn frequency spectrum resource information that oneself need is sent according to the coded system of no-rate codes packets of information is encoded and framing, the frame structure of being formed is (concrete steps are introduced below) as shown in Figure 5, emission then, the real-time whole frequency spectrum resources in the whole cognitive system carry out perception on one side, and wait for the feedback signal of receiving terminal in " replying time slot "; Need take the frequency spectrum that carries out data passes if the main user of discovery comes into play, then change step 2 over to); If receive the feedback signal of cognitive user, then change step 3) over to; If perceive new usable spectrum resource, then change step 5) over to;
2) the main user that perception the is obtained frequency spectrum resource that need take discharges no longer all and holds over, and utilizes all the other usable spectrum resources to continue to transmit the Frame that will send;
3) confirm to receive the feedback signal of cognitive user after, the type of differentiating feedback signal immediately is type one or type two, if type one illustrate that data passes finishes, then transmitting terminal stops transmission, if type two then changes step 4) over to;
4) according to receiving the frequency of signal, the feedback of differentiating type two by which frequency spectrum receives, and stops at immediately on these frequency spectrums and continue Data transmission, only utilizes all the other available spectrum resources, and all the other available spectrum resource updates are designated as f
c, change step 1) over to;
5) transmitting terminal is attempting receiving in " replying time slot " on the frequency spectrum resource that newly perceives the feedback of receiving terminal, if confirm to receive the feedback of receiving terminal on this frequency spectrum, then changes step 6) over to; If find that before receiving feedback signal this frequency spectrum again by main CU, then stops at the activity on this frequency spectrum, change step 1) over to;
That 6) confirms receiving terminal is fed back to feedback kind three, represent that promptly receiving terminal thinks that equally this frequency spectrum resource is available, then on these frequency spectrums, send certain fixing affirmation information, for example send the length of forming by 16 " 1110 " and be 64 binary data, wait for the further feedback of receiving terminal; If obtain the feedback of the type four of receiving terminal, then further confirm to finish, this frequency spectrum is charged to f
c, change step 1) over to, otherwise do not upgrade f
c, change step 1) over to.
The above-mentioned coded system according to no-rate codes is encoded and framing to packets of information, and the length of establishing the information m that will transmit is L2, as follows information m is handled:
1) m is divided into several little packets, each packet length is the k2 bit, if L2 can't be divided exactly k2, then the long part of the not enough k2 of last small data packets is filled with " 0 ", so just is partitioned into
Individual length is the small data packets of k2;
2) the long small data packets of each k2 is all carried out cyclic redundancy check (CRC), be used for decoder and judge whether decoding is successful, and cyclic redundancy check (CRC) code still adopts CRC16 in this example, and each small data packets length is the k2+16 bit like this;
3) with this
Individual length is that the encoder that the small data packets of k2+16 bit is sent into certain no-rate codes (for example Raptor Code) is encoded, produce the encoded packets C that length is all the k2+16 bit endlessly, these encoded packets are designated as C=[c according to the generation of encoded packets order
0, c
1, c
2... ], the subscript of each encoded packets is represented this encoded packets residing position in the middle of entire coded sequence, utilizes 16 bits to come the subscript of presentation code bag, then can support 2
16Long encoded packets;
4) the linear block codes encoder of target 16 bit informations under each presentation code bag being sent into one 1/4 code check carries out coding protection, promptly utilize 64 bits to come the positional information of presentation code bag, and the encoded packets positional information of this 64 bit is placed on after each encoded packets;
5) adding length before each encoded packets is that 64 * 4 targeting sequencing is used for realizing bit synchronization and channel estimating, and adds the interval protection of 64 bits after each encoded packets, and protection also can be used as " replying time slot " simultaneously at interval.The frame structure of being formed as shown in Figure 5.
The method for building up (referring to Fig. 6) of cognitive user receiving terminal link may further comprise the steps:
1) receiving terminal to whole 256 frequency spectrum resources in the whole cognitive system real-time carry out perception, obtain the cognitive result of receiving terminal to the entire spectrum resource, promptly which frequency spectrum resource is idle available.If detect q usable spectrum resource, it be designated as
And 0≤q≤256;
2) receiving terminal is being attempted at f
rIn all frequency spectrums on carry out message pick-up, the frequency spectrum perception that need not to know transmitting terminal is f as a result
t, at this moment, as long as f
tWith f
rCommon factor be not empty, then receiving terminal always can receive the coded message of transmitting terminal certainly on it occurs simultaneously frequency spectrum resource;
3) when the coded frame quantity that receives reaches the quantity of coded frame of user's beacon information of transmitting terminal, begin to decipher, utilize CRC16 to judge whether that decoding is correct, if correct, changes step 6) in this example; Otherwise change step 4) over to;
4) continue to receive several coded frame, for example continue to receive 2 frames;
5) if trial and error decoding again successfully decoded, changes step 6) over to; Otherwise change step 4) over to;
6) decoding finishes, but receiving terminal is designated as f with the frequency spectrum resource of all received code frames
c, f
cBe the set of the usable spectrum resource that perceives jointly of transmitting terminal and receiving terminal, and at f
cThe feedback signal of replying transmission types one on the time slot of intermediate frequency spectrum resource;
7) if receiving terminal is not all received the coded frame of transmitting terminal in continuous 3 time slots next, then at f
cIn all frequency spectrum resource reply the feedback signal that sends twice type one on the time slot, be used for notifying transmitting terminal;
8) the transmitting terminal initialization system information m that obtains according to decoding success of receiving terminal
s, learn the requirement of transmitting terminal, thereby finished the foundation of cognitive user receiving terminal link;
The maintaining method (referring to Fig. 7) of cognitive user receiving terminal link may further comprise the steps:
1) after communication link is set up, on one side receiving terminal utilizes f
cIn frequency spectrum resource receive the Frame that transmitting terminal transmits, on one side real-time whole frequency spectrum resources in the whole cognitive system carry out perception, if successfully decoded during this period, successfully recover the full detail data that transmitting terminal will send, then change step 2 over to); If perception is found that main user comes into play and need be taken the frequency spectrum that carries out data passes, then change step 3) over to; If perceive new usable spectrum resource, then change step 4) over to;
2) receiving terminal all f in " replying time slot "
cThe feedback of transmission types one on the frequency spectrum resource of mark is informed that transmitting terminal stops to send data immediately, thereby is finished the transmission of whole data;
3) the main user that perception the is obtained frequency spectrum resource that need take is labeled as f
z, and the feedback of transmission types two in " replying time slot " on these frequency spectrums, and with f
zThe frequency spectrum resource of middle mark is at f
cIn shift out, change step 1) over to;
4) in " replying time slot " of perceiving new usable spectrum resource, send the feedback of several times type three to transmitting terminal, and on these frequency spectrums, attempt to receive the affirmation signal of transmitting terminal, if receive the affirmation signal of transmitting terminal, then the feedback of transmission types four is done further affirmation again, and the usable spectrum resource that these are new is incorporated f into
c, change step 1) over to; If do not receive, then change step 1) over to.
Shared in the whole process to four kinds of feedbacks, be called type one, type two, type three and type four, so can distinguish with two bits of data in theory and represent this four kinds of feedbacks, for example " 01 " represents type one, " 10 " expression type two, " 11 " expression type three, " 00 " expression type four.But consider in the wireless channel transmission and may cause interference data; so represent a kind of feedback kind with 6 Bit datas here: " 010101 " expression type one; " 101010 " expression type two; " 111111 " expression type three; " 000000 " expression type four, and these data are added that the chnnel coding of a sixth code check protects.At last, through adding " the feedback frame head indicates " sequence of one 12 bit long before the data of coding protection, form a length jointly the feedback data frame that is 48 bits.
Claims (2)
1. based on the foundation and the maintaining method of the cognition radio communication link of no-rate codes, it is characterized in that comprising the method for building up of cognitive user transmitting terminal link and the method for building up of cognitive user receiving terminal link, the feedback of the type one of the following stated represents that receiving terminal has successfully received data, and the feedback of type three represents that receiving terminal thinks that this frequency spectrum resource can use;
If: whole frequency spectrum resources has n in the whole cognitive system, uses label f=[f respectively
1, f
2... ..., f
n] come mark, when a certain cognitive user inserts, there are not other cognitive user to insert at identical time slot,
The method for building up of cognitive user transmitting terminal link may further comprise the steps:
1) transmitting terminal carries out perception to whole n frequency spectrum resources in the whole cognitive system, and it is idle available obtaining which frequency spectrum resource, establishes and detects p usable spectrum resource, and it is designated as
And 0≤p≤n; The detection usable spectrum resource that transmitting terminal is real-time when finding that the usable spectrum resource changes, is upgraded f in real time
t
2) if usable spectrum resource f
tBe empty set, promptly current all frequency spectrum resources are all occupied, then change the step 1) perception again of cognitive user transmitting terminal link establishing method over to; If usable spectrum resource f
tNot empty set, then change the step 3) of cognitive user transmitting terminal link establishing method over to;
3) with user's initialization system information m of cognitive user
sCoded system according to no-rate codes is encoded and framing to packets of information; Use t
iThe presentation code frame, wherein i is the numbering of coded frame, i=0,1,2,
4) transmitting terminal is with each coded frame and the current usable spectrum resource f that perceives
tIn the usable spectrum resource do the emission that correspondence is carried out coded frame, each frequency spectrum resource is all regarded a subchannel as; Concrete mapping ruler is: if imodp=k, and k ≠ 0, then coded frame is just with the
Individual subchannel sends; If imod p=0, then coded frame is just with the
Individual subchannel sends;
5) transmitting terminal produces coded frame endlessly according to the coding rule of no-rate codes and informs that up to receiving terminal it stops to send, simultaneously at current usable spectrum resource f
tOn reply the feedback signal of intercepting receiving terminal in the time slot, if listen to the step 6) that the feedback signal of type one then changes cognitive user transmitting terminal link establishing method over to; Otherwise, the process of the step 5) of continuation cognitive user transmitting terminal link establishing method;
6) transmitting terminal stops to continue to produce coded frame and stopping emission immediately, then at all current usable spectrum resource f
tOn reply the feedback signal of intercepting receiving terminal in the time slot, and all frequency spectrum resources that can receive the feedback signal of type three are noted down separately, be designated as f
c, f
cIn all frequency spectrum resources be exactly cognitive user transmitting terminal and receiving terminal the usable spectrum resource of common approval, thereby finished the foundation of cognitive user transmitting terminal link;
The method for building up of cognitive user receiving terminal link may further comprise the steps:
1) receiving terminal carries out perception to whole n frequency spectrum resources in the whole cognitive system, and it is idle available obtaining which frequency spectrum resource, establishes and detects q usable spectrum resource, and it is designated as
And 0≤q≤n; The detection usable spectrum resource that receiving terminal is real-time when finding that the usable spectrum resource changes, is upgraded f in real time
r
2) receiving terminal is being attempted at t
rIn all frequency spectrums on carry out message pick-up, the frequency spectrum perception that need not to know transmitting terminal is f as a result
t, at this moment, as long as f
tWith f
rCommon factor be not empty, then receiving terminal always can receive the coded message of transmitting terminal certainly on it occurs simultaneously frequency spectrum resource;
3) when the coded frame quantity that receives reaches the quantity of coded frame of user's beacon information of transmitting terminal, begin to decipher, and utilize cyclic redundancy check (CRC) to judge whether that decoding is correct, if correctly, change the step 6) of cognitive user receiving terminal link establishing method over to; Otherwise change the step 4) of cognitive user receiving terminal link establishing method over to;
4) continue to receive several encoded packets;
5) if trial and error decoding again successfully decoded, changes the step 6) of cognitive user receiving terminal link establishing method over to; Otherwise change the step 4) of cognitive user receiving terminal link establishing method over to;
6) decoding finishes, but receiving terminal is designated as f with the frequency spectrum resource of all received code frames
c, f
cBe the set of the usable spectrum resource that transmitting terminal and receiving terminal perceived jointly, and at f
cThe feedback signal of replying transmission types one on the time slot of intermediate frequency spectrum resource;
7) if receiving terminal is not all received the coded frame of transmitting terminal in continuous 3 time slots next, then at f
cIn all frequency spectrum resource reply the feedback signal that sends twice type one on the time slot, be used for notifying transmitting terminal;
8) the transmitting terminal initialization system information m that obtains according to decoding success of receiving terminal
s, learn the requirement of transmitting terminal, thereby finished the foundation of cognitive user receiving terminal link.
2. the foundation and the maintaining method of the cognition radio communication link based on no-rate codes according to claim 1, it is characterized in that the coded system according to no-rate codes in the method for building up of cognitive user transmitting terminal link encodes and framing to packets of information, its step is as follows:
1), establishes the information m that will transmit according to initialization system information
sLength be L1, m1 is divided into " L1/k1] individual small data packets, each small data packets length is k1, if L1 can't divide exactly k1, then the long part of the not enough k1 of last small data packets is filled with " 0 ";
2) utilize cyclic redundancy check (CRC) code to carry out cyclic redundancy check (CRC) to the long small data packets of each k1, each small data packets length is increased to the k1+r1 bit accordingly according to the length r1 of the cyclic redundancy check (CRC) code that adopts;
3) will
Individual length is that the encoder that the small data packets of k1+r1 bit is sent into no-rate codes is encoded, and according to the generation order of encoded packets these encoded packets is designated as C=[c
0, c
1, c
2... ], the subscript of each encoded packets is represented this encoded packets residing position in the middle of entire coded sequence, utilizes g bit to come the subscript of presentation code bag;
4) the linear block codes encoder of the subscript of each encoded packets being sent into one 1/4 code check is encoded, generation length be the data of g * 4 bits as location mark, and location mark is placed on after each encoded packets;
5) adding length before each encoded packets is that 64 * 4 targeting sequencing is used for realizing bit synchronization and channel estimating, and adds the interval of 64 bits after each encoded packets, as " replying time slot ";
6) after targeting sequencing, also will add the initialization preamble sequence that length is 64 * 4 bits before the digital coding bag, the preamble sequence content comprises the customer identification number of transmitter and target receiver, be used for User Recognition and the auxiliary bit synchronization that realizes, finish coding and framing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100637103A CN101325461B (en) | 2008-07-25 | 2008-07-25 | Method for establishing and maintaining cognition radio communication link based on non-speed code |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008100637103A CN101325461B (en) | 2008-07-25 | 2008-07-25 | Method for establishing and maintaining cognition radio communication link based on non-speed code |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010105669714A Division CN102026247B (en) | 2008-07-25 | 2008-07-25 | Establishment and maintenance method of cognitive radio communication link based on non-rate code |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101325461A CN101325461A (en) | 2008-12-17 |
| CN101325461B true CN101325461B (en) | 2011-04-27 |
Family
ID=40188822
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2008100637103A Expired - Fee Related CN101325461B (en) | 2008-07-25 | 2008-07-25 | Method for establishing and maintaining cognition radio communication link based on non-speed code |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101325461B (en) |
Families Citing this family (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102083191B (en) * | 2009-11-30 | 2014-01-08 | 中国移动通信集团山东有限公司 | Resource allocation method and device as well as data transmission method and equipment |
| CN101742570B (en) * | 2009-12-29 | 2012-08-29 | 浙江大学 | Distributed packet access method based on no-rate codes in cognitive radio |
| CN101741516B (en) * | 2009-12-29 | 2013-05-08 | 电子科技大学 | Speed-free mode-based frame level encoding and decoding method |
| CN101765124B (en) * | 2010-01-13 | 2012-01-04 | 南京邮电大学 | Channel capacity analytical method in chance spectra sharing system |
| CN101800997B (en) * | 2010-02-24 | 2013-08-07 | 华为技术有限公司 | Frequency spectrum resource allocation method and device |
| CN101815311A (en) * | 2010-03-10 | 2010-08-25 | 北京航空航天大学 | Link establishment method by taking user as center in cognitive radio scene |
| CN101820333B (en) * | 2010-04-16 | 2012-12-19 | 浙江大学 | Distribution type access transmission method of cognitive multi-user and multi-channel system based on rate-free code |
| CN102377494B (en) * | 2010-08-17 | 2014-07-30 | 华为技术有限公司 | Frequency spectrum sensing method, device and system |
| WO2012159297A1 (en) * | 2011-06-27 | 2012-11-29 | 华为技术有限公司 | Method and device for wireless link recovery |
| CN103037437A (en) * | 2011-10-10 | 2013-04-10 | 国民技术股份有限公司 | Bulk data transmission method and system of radio frequency link and radio frequency sending/receiving terminal |
| CN103067925B (en) * | 2011-10-21 | 2017-10-17 | 中兴通讯股份有限公司 | The reallocating method and system of a kind of cognitive radio system lead code form |
| CN103517400B (en) * | 2012-06-26 | 2017-04-05 | 京信通信系统（广州）有限公司 | Femto base station SON processes UE cut-in method and device |
| WO2014065873A1 (en) | 2012-10-22 | 2014-05-01 | Jeff Willey | Control messaging in multislot link layer flit |
| CN103702432B (en) * | 2013-12-03 | 2016-09-28 | 上海无线通信研究中心 | A kind of uplink enhancement method based on geographic position data storehouse |
| CN103986553B (en) * | 2014-04-04 | 2017-03-01 | 浙江大学 | The stop-and-wait transmission method of suitable physical layer no rate coding transmission |
| CN105472744B (en) * | 2014-09-02 | 2020-07-31 | 中兴通讯股份有限公司 | Data transmission method and device |
| CN104640228A (en) * | 2015-01-26 | 2015-05-20 | 哈尔滨工业大学深圳研究生院 | Non-preemptive spectrum access method based on negotiation |
| CN115549848A (en) * | 2021-06-29 | 2022-12-30 | 华为技术有限公司 | Data transmission method and communication device |
| CN114499751B (en) * | 2021-12-10 | 2023-06-30 | 北京邮电大学 | List enhancement decoding method and device based on polarized ALOHA |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1739307A (en) * | 2001-11-30 | 2006-02-22 | 美商内数位科技公司 | Method and apparatus for optimal utilization of a radio channel based on cognition model data |
| CN100471093C (en) * | 2006-04-13 | 2009-03-18 | 电子科技大学 | Chain circuit building method in cognitive radio field |
-
2008
- 2008-07-25 CN CN2008100637103A patent/CN101325461B/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1739307A (en) * | 2001-11-30 | 2006-02-22 | 美商内数位科技公司 | Method and apparatus for optimal utilization of a radio channel based on cognition model data |
| CN100471093C (en) * | 2006-04-13 | 2009-03-18 | 电子科技大学 | Chain circuit building method in cognitive radio field |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101325461A (en) | 2008-12-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101325461B (en) | Method for establishing and maintaining cognition radio communication link based on non-speed code | |
| US9294959B2 (en) | Radio communication system, mobile station apparatus, base station apparatus, and radio communication method in radio communication system | |
| CN101801078B (en) | Controlled superposition coding in multi-user communication systems | |
| AU695694B2 (en) | Air interface adapting method for a mobile radio system | |
| US9112696B2 (en) | Radio communication apparatus and a method of transmitting a retransmission packet | |
| RU2005139127A (en) | MOBILE COMMUNICATION SYSTEM AND METHOD FOR PROCESSING SIGNALS IN IT | |
| EP1803286B1 (en) | A method for the selection of forward error correction (fec)/ constellation pairings for digital transmitted segments based on learning radio link adaptation (rla) | |
| US6292516B1 (en) | Communication system using packets stuffed with test words for evaluating data reception characteristics while providing increased data throughput | |
| WO2005027355A3 (en) | Incremental redundancy transmission for multiple parallel channels in a mimo communication system | |
| WO1997030563A3 (en) | Method and arrangement for channel allocation in a radio communications system | |
| CA2475859A1 (en) | Transport block set transmission using hybrid automatic repeat request | |
| CN101578801A (en) | Multiplexing of control and data with varying power offsets in a SC-FDMA system | |
| EP2160876B1 (en) | Method, signal and apparatus for managing the transmission and receipt of broadcast channel information | |
| JP2005527147A5 (en) | ||
| CN103051928A (en) | Method and device for wireless audio and video data transmission | |
| US10129789B2 (en) | Methods for encoding and decoding frames in a telecommunication network | |
| JPWO2020250325A5 (en) | ||
| EP3611855B1 (en) | False positive detection in nb-iot downlink control channel based on effective and scheduled code rate | |
| CN102026247B (en) | Establishment and maintenance method of cognitive radio communication link based on non-rate code | |
| EP2340628B1 (en) | Telecommunication method and apparatus | |
| EP1401139B1 (en) | Data communication device and data communication method | |
| CN103188060A (en) | Retransmission method and retransmission device | |
| WO2007108751A2 (en) | Method of reducing feedback signalling using sic | |
| CN101964693A (en) | Method for data transmission by using wireless channel interference | |
| CN101160849B (en) | A communication device, a method of operating a communication device, and a communication system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110427 Termination date: 20120725 |