CN113411906B - Conflict detection method and device - Google Patents

Conflict detection method and device Download PDF

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CN113411906B
CN113411906B CN202110546609.9A CN202110546609A CN113411906B CN 113411906 B CN113411906 B CN 113411906B CN 202110546609 A CN202110546609 A CN 202110546609A CN 113411906 B CN113411906 B CN 113411906B
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random access
physical root
root index
detection
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CN113411906A (en
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李立华
方红雨
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Beijing University of Posts and Telecommunications
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W74/00Wireless channel access
    • H04W74/08Non-scheduled access, e.g. ALOHA
    • H04W74/0833Random access procedures, e.g. with 4-step access
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/14Relay systems
    • H04B7/15Active relay systems
    • H04B7/185Space-based or airborne stations; Stations for satellite systems
    • H04B7/1851Systems using a satellite or space-based relay
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W74/00Wireless channel access
    • H04W74/08Non-scheduled access, e.g. ALOHA
    • H04W74/0833Random access procedures, e.g. with 4-step access
    • H04W74/0841Random access procedures, e.g. with 4-step access with collision treatment
    • H04W74/0858Random access procedures, e.g. with 4-step access with collision treatment collision detection

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Abstract

The invention provides a method and a device for detecting conflict. The method is applied to network side equipment, and comprises the following steps: receiving a random access sequence sent by a user terminal, wherein the random access sequence comprises a leader sequence and a label sequence; synchronously completing timing detection of the leader sequence and collision detection of the label sequence based on the random access sequence; wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime. The invention provides a low earth orbit satellite collision detection scheme based on a label sequence, and the label sequence is introduced for collision detection in the random access process, so that the collision detection and the timing detection are completed at the same step. The random access of the low earth orbit satellite based on competition can be simplified to two steps, thereby greatly shortening the access time delay and improving the access efficiency.

Description

Conflict detection method and device
Technical Field
The invention relates to the field of low-earth-orbit satellite communication, in particular to a method and a device for detecting conflict.
Background
In a low-earth-orbit satellite communication system, due to the long distance between the satellite and the ground, the signal transmission delay is large. The random access process based on competition is divided into four steps, the main work of the first two steps is the sending detection and feedback of a lead code, and the Timing Advance (TA) obtained by detection and calculation can be used for time synchronization of an uplink, so the first two steps are mainly used for completing the uplink synchronization. The following Msg3(message 3) and Msg4(message 4) mainly work for contention resolution, and the base station allocates a unique and legal user identity to the terminal initiating access, so as to perform subsequent uplink data transmission.
In contention-based random access, the base station does not assign a preamble sequence to the terminal. When a plurality of terminals initiate Random Access, the same preamble sequence may be selected and the same Random Access time-frequency resource is selected to transmit a preamble, and then the base station detects a TC-RNTI (temporary cell radio network identifier) obtained by the preamble and feeds back the TC-RNTI to the terminals through an RAR (Random Access Response). In addition, the RAR further includes uplink scheduling information UL Grant (uplink Grant). Then these concurrent terminals will simultaneously send Msg3 to the base station based on these messages, and due to the interference of different terminal signals, the base station may not be able to receive and parse the Msg3 message sent by each terminal or barely detect the Msg3 messages of some terminals. But the base station can be aware of the access collision occurring through the reception of Msg 3.
For this, the third step and the fourth step of contention-based random access require further differentiation of terminals initiating random access, and a contention resolution mechanism is divided into two cases according to whether the UE already has a valid C-RNTI (Cell-Radio Network Temporary Identifier):
(1) The terminal already has a legal C-RNTI: the terminal sends C-RNTI MAC CE (Media access Control element) to the base station through the Msg3, the base station decodes the information and feeds back the information to the terminal, and then the terminal can use the unique C-RNTI to solve the PDCCH (Physical Downlink Control Channel) of the Msg4, and the random access is considered to be successful.
(2) The terminal has no legal C-RNTI: the terminal sends a CCCH (Common Control Channel) SDU (service Data Unit) on the Msg3, wherein the CCCH SDUs contain competition resolving identities, then the terminal uses TC-RNTI to resolve a PDCCH of the Msg4 and can also successfully resolve a competition resolving Identity MAC CE in the Msg4, if the competition resolving identities in the MAC CE are consistent with those sent by the terminal in the Msg3, the terminal considers that a random access process is successful, and the TC-RNTI is formally converted into the C-RNTI.
If the conventional four-step flow is adopted for contention-based random access, the access time is prolonged, and the access efficiency is low.
Therefore, how to complete collision detection more quickly for low-earth orbit satellite communication systems is an important issue to be solved in the industry.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a method and a device for detecting conflict.
In a first aspect, the present invention provides a method for collision detection, applied to a network side device, including:
receiving a random access sequence sent by a user terminal, wherein the random access sequence comprises a leader sequence and a label sequence;
synchronously completing timing detection of the leader sequence and collision detection of the label sequence based on the random access sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
Optionally, the receiving user terminal sends a random access sequence, where the random access sequence includes a preamble sequence and a tag sequence, and includes:
indexing u based on physical root 2 And a tag index/, determining the tag sequence;
wherein the value range of the label index L is [0, L RA -1],L RA Is the length of the leader sequence.
Optionally, the synchronously completing timing detection of a preamble sequence and collision detection of a tag sequence based on the random access sequence includes:
based on a receiving end detection model, performing cross correlation on the random access sequence and a local root sequence to obtain a first power delay spectrum, and performing peak detection to complete timing detection of the leader sequence;
According to the timing detection of the leader sequence, determining the position of a peak value, the transmission delay and the physical root index of the leader sequence;
and determining the physical root index of the label sequence according to the physical root index of the leader sequence, performing cross-correlation on the random access sequence and the label root sequence to obtain a second power time delay spectrum, and performing peak value detection.
Optionally, the determining a physical root index of a tag sequence according to the physical root index of the preamble sequence, performing cross-correlation between the random access sequence and the tag root sequence to obtain a second power delay profile, and performing peak detection includes:
determining a physical root index of the tag sequence based on a co-prime relationship of the physical root index of the preamble sequence and the physical root index of the tag sequence;
and sending a notice to the user terminal if a plurality of conditions greater than the threshold exist according to the peak value comparison between the peak value detection result and the threshold.
In a second aspect, the present invention provides a method for detecting a collision, which is applied to a user equipment, and includes:
sending a random access sequence, wherein the random access sequence comprises a leader sequence and a label sequence;
the random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence;
Wherein the physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
Optionally, the sending a random access sequence, where the random access sequence includes a preamble sequence and a tag sequence, includes:
indexing u based on physical root 2 And a tag index/, determining the tag sequence;
wherein the value range of the label index L is [0, L RA -1],L RA Is the length of the leader sequence.
In a third aspect, the present invention further provides a device for network side collision detection, including a memory, a transceiver, and a processor;
a memory for storing a computer program; a transceiver for transceiving data under control of the processor; a processor for executing the computer program in the memory and implementing the steps of:
receiving a random access sequence sent by a user terminal, wherein the random access sequence comprises a leader sequence and a label sequence;
synchronously completing timing detection of the leader sequence and collision detection of the label sequence based on the random access sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
In a fourth aspect, the present invention further provides a device for detecting user terminal collision, including a memory, a transceiver, and a processor;
A memory for storing a computer program; a transceiver for transceiving data under control of the processor; a processor for executing the computer program in the memory and implementing the steps of:
sending a random access sequence, wherein the random access sequence comprises a leader sequence and a label sequence;
the random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
In a fifth aspect, the present invention further provides a collision detection apparatus, applied to a network side device, including:
a receiving module, configured to receive a random access sequence sent by a user terminal, where the random access sequence includes a preamble sequence and a tag sequence;
a detection module, configured to synchronously complete timing detection of the preamble sequence and collision detection of the tag sequence based on the random access sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
In a sixth aspect, the present invention further provides a collision detection apparatus, applied to a user terminal, including:
A sending module, configured to send a random access sequence, where the random access sequence includes a preamble sequence and a tag sequence;
the random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence;
wherein the physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
In a seventh aspect, the present invention also provides a processor-readable storage medium, which stores a computer program for causing a processor to execute the steps of the method for collision detection as described in the first aspect above, or the steps of the method for collision detection as described in the second aspect above.
The method and the device for detecting the conflict, provided by the invention, have the advantage that the label sequence is introduced for detecting the conflict in the random access process, so that the conflict detection and the timing detection are finished at the same step. The random access of the low earth orbit satellite based on competition can be simplified to two steps, thereby greatly shortening the access time delay and improving the access efficiency.
Drawings
In order to more clearly illustrate the technical solutions of the present invention or the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a flow chart of a method of collision detection provided by the present invention;
FIG. 2 is a schematic diagram of a ZC sequence cross-correlation simulation;
FIG. 3 is a schematic diagram of a receiver detection model;
FIG. 4 is a second schematic diagram of a receiver inspection model;
FIG. 5 is a flow chart of contention-based random access for low earth orbit satellites;
FIG. 6 is a graph of the trend of the probability of collision detection as the number of colliding users increases;
FIG. 7 is a second flowchart of a collision detection method provided by the present invention;
FIG. 8 is a schematic structural diagram of a collision detection device provided in the present invention;
FIG. 9 is a second schematic structural diagram of a collision detection device provided in the present invention;
FIG. 10 is a schematic structural diagram of a collision detection apparatus provided in the present invention;
fig. 11 is a second schematic structural diagram of a collision detection apparatus provided in the present invention.
Detailed Description
The term "and/or" in the present invention describes an association relationship of associated objects, and means that there may be three relationships, for example, a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.
The term "plurality" as used herein means two or more, and other terms are analogous.
The technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The scheme of collision detection provided by the invention introduces the label sequence for collision detection in the random access process, so that the collision detection can be completed in the second step in advance. The random access of the low-orbit satellite based on competition can be simplified to two steps, so that the access time delay is greatly shortened, and the access efficiency is improved.
Fig. 1 is a schematic flow chart of a method for detecting a collision according to the present invention. As shown in fig. 1, the method comprises the steps of:
step 101, receiving a random access sequence sent by a user terminal, wherein the random access sequence comprises a leader sequence and a label sequence; wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
Specifically, the existing contention-based random access process all adopts a four-step flow, the main work of the first two steps is the sending detection and feedback of a lead code, the timing advance TA obtained by detection and calculation can be used for time synchronization of an uplink, the main work of the last two steps is the solution of contention, and a base station allocates a unique and legal user identity for a terminal initiating access, so as to perform subsequent uplink data transmission.
Considering that ZC sequences have good cross-correlation performance, when the absolute value of the difference value of the physical root indexes of the two ZC sequences is mutually prime with the length of the ZC sequences, the cross-correlation value of the two ZC sequences does not generate a peak value and is very small, FIG. 2 is a simulation schematic diagram of the cross-correlation of the ZC sequences, and as shown in FIG. 2, the physical root indexes of the two ZC sequences are respectively u 1 =10,u 2 Length of ZC sequence L-11 RA 839, the cross-correlation value is obtained to be about
Figure BDA0003073916770000071
It can be seen that the physical root indices are different and the correspondingly generated ZC sequences do not interfere with peak detection of each other. According to this particular property of ZC sequences, the invention reconstructs the low-orbit satellite random access sequence (random access preamble) as follows:
Figure BDA0003073916770000081
wherein, the first and the second end of the pipe are connected with each other,
Figure BDA0003073916770000082
denotes the preamble sequence and is indexed by the physical root 1 The generated ZC sequence is a sequence of a ZC,
Figure BDA0003073916770000083
representing a sequence of tags, indexed by a physical root u 2 Generated ZC sequence, physical root index u 1 And u 2 Are relatively prime. Physical root index u 1 And u 2 There are various coprime conditions, and in the present invention, the coprime relationship between the two is expressed as the physical root index u 2 =u 1 +1 or u 2 =u 1 -1。
And 102, synchronously finishing the timing detection of the leader sequence and the collision detection of the label sequence based on the random access sequence.
And the network side equipment performs label sequence collision detection after finishing preamble sequence timing detection based on the received random access sequence, and the preamble sequence timing detection and the label sequence collision detection are finished in the same step.
The method for detecting the conflict provided by the invention leads the label sequence to be used for detecting the conflict in the random access process, so that the conflict detection can be completed in the second step in advance. The random access of the low earth orbit satellite based on competition can be simplified to two steps, thereby greatly shortening the access time delay and improving the access efficiency.
On the basis of the foregoing embodiment, optionally, the receiving user terminal sends a random access sequence, where the random access sequence includes a preamble sequence and a tag sequence, and includes:
indexing u based on physical root 2 And a tag index/, determining the tag sequence;
wherein the value range of the label index L is [0, L RA -1],L RA Is the length of the leader sequence.
Specifically, the random access sequence in the present invention is composed of two parts (refer to formula (1)), wherein the preamble sequence
Figure BDA0003073916770000085
Generating by adopting ZC root sequence cyclic displacement:
x u,v =x u ((n+C v )modL RA ) (2)
wherein the expression of the root ZC sequence is as follows,
Figure BDA0003073916770000084
where u is the physical root index, L RA Is the length of the leader sequence. Length of preamble sequence L in 5G system RA Can be 839, 139, 571 or 1151, and two lengths L are generally adopted RA 839 or L RA 139. The system is at eachThe cell allocates 64 preamble sequences at most for the user to randomly select, the preamble sequences are generated by one or more ZC root sequences through cyclic shift, if one ZC root sequence can not generate 64 preamble sequences, the logical root sequence number i is shifted backwards by one bit in an increasing mode, a corresponding physical root index u is found, and the rest preamble sequences are generated in the same mode. C v For cyclic shift, details are not described herein, and reference can be made to 3gpp.ts 38.211 v16.3.0.
N in formula (2) represents a ZC sequence obtained by formula (3), and the expression of formula (2) means that the ZC sequence obtained by formula (3) is subjected to cyclic shift C v And ZC sequence length L RA And obtaining a random access leader sequence after cyclic shift.
And the tag sequence
Figure BDA0003073916770000091
For new addition, the ZC root sequence is also generated by cyclic shift, and the specific formula is as follows:
Figure BDA0003073916770000092
the method for generating the ZC root sequence is the same as the method for calculating the preamble sequence according to formula (3), and is not described herein again. L represents the label index and has a value range of [0, L RA -1],L RA Indicates the length of the preamble sequence. And u is 1 And u 2 The corresponding ZC sequences are the same length. Its physical root index u 1 And u 2 The values are different, in the present invention, u 2 Can take the value u 1 +1 or u 1 -1. By setting the label sequence to mark a unique mark l for each lead code, even different users adopt the same lead sequence, the different users can be distinguished by detecting the label sequence, because the physical root index u of the label sequence 2 Physical root index u with preamble sequence 1 The introduction of the tag sequence does not affect the timing detection of the leader sequence.
When N terminals initiate random access, the same preamble sequence is adoptedColumns, i.e. physical root index u 1 And cyclic displacement C v Similarly, preambles are transmitted in the same PRACH (Physical Random Access Channel) time-frequency resource, and the N preamble sets may be represented as N preamble sets
Figure BDA0003073916770000093
Wherein u is 1 Physical root index, u, representing preamble sequence 2 A physical root index indicating a tag sequence, and L is a set of tag indices of the tag sequence, i.e., L ═ L 1 ,l 2 ,...,l N The random numerical values randomly selected by N users satisfy l n ∈[0,L RA ) N is 1, 2. When the number of the accessed user terminals exceeds the leader sequence L RA Length value of, physical root index u can be changed 1 And u 2 Expression of co-prime relationships, e.g. start u 2 =u 1 +1, when the number of accessed user terminals exceeds the leader sequence L RA The remaining user terminals can adopt u 2 =u 1 -1 to calculate the corresponding tag sequence. The above is merely an illustration, u in the present invention 1 And u 2 The co-prime relationship may exist in various ways and is not specifically limited herein.
The method for detecting the conflict introduces the label sequence for detecting the conflict in the random access process, so that the conflict detection can be completed in the second step in advance. The random access of the low earth orbit satellite based on competition can be simplified to two steps, thereby greatly shortening the access time delay and improving the access efficiency.
On the basis of the foregoing embodiment, optionally, the synchronously completing timing detection of a preamble sequence and collision detection of a tag sequence based on the random access sequence includes:
based on a receiving end detection model, performing cross correlation on the random access sequence and a local root sequence to obtain a first power delay spectrum, and performing peak detection to complete timing detection of the leader sequence;
according to the timing detection of the leader sequence, determining the position of a peak value, the transmission delay and the physical root index of the leader sequence;
And determining the physical root index of the label sequence according to the physical root index of the leader sequence, performing cross-correlation on the random access sequence and the label root sequence to obtain a second power time delay spectrum, and performing peak value detection.
Specifically, the detection of the random access sequence includes two parts, one part is a timing detection process of the preamble sequence, as shown in fig. 3, the receiving end detection model mainly generates a corresponding second power delay spectrum after preprocessing the received signal, and performs peak detection according to the second power delay spectrum.
The received signal is a random access sequence sent by a user terminal, wherein the random access sequence comprises a leader sequence and a label sequence.
Step 301, preprocessing a received signal, wherein the preprocessing includes: removing cyclic prefix, time domain filtering, down sampling and the like, and performing Discrete Fourier Transform (DFT) on the output signal to obtain a signal y (n);
step 302, performing discrete Fourier transform on the local sequence, and conjugating the obtained result to obtain a signal z (n);
and step 303, performing cross-correlation calculation on y (n) and z (n), wherein the cross-correlation calculation is performed by multiplying the corresponding points of the y (n) and the z (n).
And performing Inverse Discrete Fourier Transform (IDFT) on the obtained result, then performing modulus extraction and merging operations to obtain a first power delay spectrum of the random access sequence, wherein when the local sequence and the random access sequence have the same ZC root sequence, a corresponding peak point appears in the first power delay spectrum obtained by the cross-correlation operation, and then performing peak detection on the obtained first power delay spectrum to obtain a position of the peak, a transmission delay, and a physical root index of the preamble sequence, where there may be a plurality of physical root indexes of the preamble sequence. Conversely, if a peak occurs, the physical root index of the preamble sequence is the physical root index of the current local root sequence. And the timing detection of the preamble sequence is completed through the first power delay spectrum.
The other part is the collision detection of the tag sequence, after the timing detection of the preamble sequence is completed, the collision detection of the tag sequence is started by combining the receiving end detection model, as shown in fig. 4:
step 401, preprocessing a received signal, wherein the preprocessing includes: removing cyclic prefix, time domain filtering, down sampling and the like, and performing Discrete Fourier Transform (DFT) on the output signal to obtain a signal y (e); here, y (e) is the same as y (n) in step 301.
Step 402, performing discrete Fourier transform on the tag root sequence, and conjugating the obtained result to obtain a signal z (e);
step 403, performing cross-correlation calculation on y (e), z (e), and the like, multiplying the two corresponding points to obtain a cross-correlation function value, performing Inverse Discrete Fourier Transform (IDFT) on the obtained result, then performing modulus extraction and merging operations to obtain a second power delay spectrum of the random access sequence, and when the tag root sequence and the random access sequence have the same ZC root sequence, generating a corresponding peak point in the second power delay spectrum obtained by the cross-correlation calculation, and then performing peak detection on the obtained second power delay spectrum.
The method for detecting the conflict provided by the invention leads the label sequence to be used for detecting the conflict in the random access process, so that the conflict detection can be completed in the second step in advance. The random access of the low earth orbit satellite based on competition can be simplified to two steps, thereby greatly shortening the access time delay and improving the access efficiency.
On the basis of the foregoing embodiment, optionally, the determining a physical root index of a tag sequence according to the physical root index of the preamble sequence, performing cross-correlation between the random access sequence and the tag root sequence to obtain a second power delay profile, and performing peak detection includes:
determining the tag sequence physical root index based on a co-prime relationship between the physical root index of the leader sequence and the tag sequence physical root index;
and sending a notice to the user terminal if a plurality of conditions greater than the threshold exist according to the peak value comparison between the peak value detection result and the threshold.
Specifically, the tag root sequence is determined based on the physical root index of the preamble sequence in step 303.
According to the physical root index u of the preamble sequence obtained in step 303 1 Based on a co-prime relationship between the physical root index of the leader sequence and the physical root index of the tag sequence, e.g. u 2 Value of u 1 +1 or u 1 -1, the physical root index u of the tag sequence can be determined 2 Is further indexed by the physical root of the tag sequence, u 2 Determining a corresponding label root sequence according to the formula (4), obtaining a signal z (e) according to the step 402, and similarly, if the label root sequence has a ZC root sequence identical to that of the random access sequence, generating a corresponding peak value, and further determining the position of the peak value.
Then, comparing the peak detection result with a preset threshold peak value, if a plurality of conditions greater than the threshold exist, indicating that a plurality of user terminals exist, selecting the same preamble sequence at the same time, selecting the same random access time-frequency resource to transmit the preamble, that is, under the condition that a conflict exists, the network side equipment detects the conflict, and transmitting a notification to the corresponding user terminal.
The predetermined threshold peak value may be determined in various ways, such as empirically set, or determined according to statistical results over a period of time. And are not limited herein.
The method for detecting the conflict provided by the invention leads the label sequence to be used for detecting the conflict in the random access process, so that the conflict detection can be completed in the second step in advance. The random access of the low earth orbit satellite based on competition can be simplified to two steps, thereby greatly shortening the access time delay and improving the access efficiency.
The low earth orbit satellite is based on a contention based random access procedure as shown in fig. 5.
Before initiating random access, the terminal generates a lead code according to the configuration information sent by the base station and sends the lead code on the corresponding PRACH resource.
The base station carries out timing detection after receiving the lead code and can detect the access conflict, and for the leading sequence generating the conflict, the base station timely informs the terminal that the conflict occurs, and then the terminal stops the random access flow.
Compared with the traditional random access conflict solution scheme, the scheme reduces the random access time delay and avoids the waste of wireless resources caused by access conflict.
The configuration information here includes at least one of:
PRACHConfig-Index indicates a preamble format and time domain resources;
msg 1-frequcnyStart indicates preamble frequency domain resources;
msg1-FDM indicates preamble frequency domain resources;
the above is merely an exemplary illustration, and the specific configuration information may be more cases, and is not limited herein.
Through the description of the embodiment, the invention also carries out simulation, and the specific simulation result refers to fig. 6.
The proposed conflict detection algorithm based on the tag sequence performs simulation analysis and evaluates the performance of the algorithm. Assuming that the number of concurrent access terminals is U-5, the number of access-collided terminals is C-3-5, and other simulation parameters are shown in table 6-1. For the design herein, the preamble sequence physical root index u for these 5 concurrent terminals 1 Value 40, tag sequence root index u 2 Value 41, cyclic shift C of conflicting terminals v Value 37, cyclic shift C of the remaining terminals v Taking the value 41, the label index l of each terminal is randomly selected. The detection probability was obtained by 10000 times of simulation in AWGN channel.
TABLE 6-1 simulation parameters
Figure BDA0003073916770000141
As shown in fig. 6, as the number of colliding terminals increases, the probability of collision detection increases.
Fig. 7 is a second flowchart of the collision detection method provided by the present invention. As shown in fig. 7, the method for detecting a collision is applied to a user terminal, and includes:
step 701, sending a random access sequence, wherein the random access sequence comprises a leader sequence and a tag sequence;
the random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
Specifically, the existing contention-based random access process all adopts a four-step flow, the main work of the first two steps is the sending detection and feedback of a lead code, the timing advance TA obtained by detection and calculation can be used for time synchronization of an uplink, the main work of the last two steps is the solution of contention, and a base station allocates a unique and legal user identity for a terminal initiating access, so as to perform subsequent uplink data transmission.
Considering that ZC sequences have good cross-correlation performance, when the absolute value of the difference value of the physical root indexes of the two ZC sequences is mutually prime with the length of the ZC sequences, the cross-correlation value of the two ZC sequences does not generate a peak value and is very small, FIG. 2 is a simulation schematic diagram of the cross-correlation of the ZC sequences, and as shown in FIG. 2, the physical root indexes of the two ZC sequences are respectively u 1 =10,u 2 Length of ZC sequence L-11 RA 839, the cross-correlation value is obtained to be about
Figure BDA0003073916770000151
It can be seen that the physical root indices are different and the correspondingly generated ZC sequences do not interfere with peak detection of each other. According to this particular property of ZC sequences, the invention reconstructs the low-orbit satellite random access sequence (random access preamble) as follows:
Figure BDA0003073916770000152
wherein the content of the first and second substances,
Figure BDA0003073916770000153
denotes the preamble sequence and is indexed by the physical root 1 The generated ZC sequence is a sequence of a ZC,
Figure BDA0003073916770000154
indicates the label sequence is indexed by the physical root as u 2 Generated ZC sequence, physical root index u 1 And u 2 Are relatively prime. Physical root index u 1 And u 2 There are many cases of co-prime, and in the present invention, the physical root index u 2 Can take the value u 1 +1 or u 1 -1。
And the user terminal sends the random access sequence to the network side equipment, so that the network side equipment performs the collision detection of the label sequence after finishing the timing detection of the leader sequence, and the timing detection of the leader sequence and the collision detection of the label sequence are finished in the same step.
The method for detecting the conflict provided by the invention leads the label sequence to be used for detecting the conflict in the random access process, so that the conflict detection can be completed in the second step in advance. The random access of the low earth orbit satellite based on competition can be simplified to two steps, thereby greatly shortening the access time delay and improving the access efficiency.
On the basis of the foregoing embodiment, optionally, the sending a random access sequence, where the random access sequence includes a preamble sequence and a tag sequence, includes:
indexing u based on physical root 2 And a tag index/, determining the tag sequence;
wherein the value range of the label index L is [0, L RA -1],L RA Is the length of the leader sequence.
Specifically, the random access sequence in the present invention is composed of two parts (refer to formula (1)), wherein the preamble sequence
Figure BDA0003073916770000155
Generating by adopting ZC root sequence cyclic displacement:
x u,v =x u ((n+C v )modL RA ) (2)
wherein the expression of the root ZC sequence is as follows,
Figure BDA0003073916770000156
u is the physical root index, L RA Is the length of the leader sequence. Length of preamble sequence L in 5G system RA Can be 839, 139, 571 or 1151, and two lengths L are generally adopted RA 839 or L RA 139. The system distributes 64 preamble sequences at most for users to randomly select in each cell, the preamble sequences are generated by cyclic shift of one or more ZC root sequences, if one ZC root sequence can not generate 64 preamble sequences, the logical root sequence number i is shifted backwards by one bit in an increasing mode, the corresponding physical root index u is found, and the rest preamble sequences are generated in the same mode. C v For cyclic shift, details are not repeated herein, and reference can be made to 3gpp.ts 38.211 v16.3.0.
N in formula (2) represents a ZC sequence obtained by formula (3), and the expression of formula (2) means that the ZC sequence obtained by formula (3) is subjected to cyclic shift C v And ZC sequence length L RA And obtaining a random access leader sequence after cyclic shift.
And a tag sequence
Figure BDA0003073916770000161
For new addition, the ZC root sequence is also generated by cyclic shift, and the specific formula is as follows:
Figure BDA0003073916770000162
the method for generating the ZC root sequence is the same as the method for calculating the preamble sequence according to formula (3), and is not described herein again. L represents the label index and has a value range of [0, L RA -1],L RA Indicates the length of the ZC sequence. And u is 1 And u 2 The corresponding ZC sequences are the same length. Its physical root index u 1 And u 2 Different values are obtained in the inventionIn u 2 Can take the value u 1 +1 or u 1 -1. By setting the label sequence to mark a unique mark l for each lead code, even different users adopt the same lead sequence, the different users can be distinguished by detecting the label sequence, because the physical root index u of the label sequence 2 Physical root index u with preamble sequence 1 The introduction of the tag sequence does not affect the timing detection of the leader sequence.
When N terminals initiate random access, the same leader sequence, namely the physical root index u, is adopted 1 And cyclic displacement C v Similarly, preambles are transmitted in the same PRACH time-frequency resource, and the N preamble sets may be represented as
Figure BDA0003073916770000163
Wherein u is 1 Physical root index, u, representing preamble sequence 2 A physical root index indicating a tag sequence, and L is a set of tag indices of the tag sequence, i.e., L ═ L 1 ,l 2 ,...,l N The random numbers randomly selected by N users satisfy l n ∈[0,L RA ),n=1,2,...,N。
The method for detecting the conflict provided by the invention leads the label sequence to be used for detecting the conflict in the random access process, so that the conflict detection can be completed in the second step in advance. The random access of the low earth orbit satellite based on competition can be simplified to two steps, thereby greatly shortening the access time delay and improving the access efficiency.
Fig. 8 is a schematic structural diagram of a network-side collision detection device provided in the present invention, and as shown in fig. 8, the network-side collision detection device includes a memory 820, a transceiver 810 and a processor 800; wherein the processor 800 and the memory 820 may also be physically separated.
A memory 820 for storing a computer program; a transceiver 810 for transceiving data under the control of the processor 800.
In particular, transceiver 810 is used to receive and transmit data under the control of processor 800.
Where in fig. 8, the bus architecture may include any number of interconnected buses and bridges, with various circuits being linked together, particularly one or more processors represented by processor 800 and memory represented by memory 820. The bus architecture may also link various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 810 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like.
The processor 800 is responsible for managing the bus architecture and general processing, and the memory 820 may store data used by the processor 800 in performing operations.
The processor 800 may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or a Complex Programmable Logic Device (CPLD), and may also have a multi-core architecture.
The processor 800, by calling the computer program stored in the memory 820, is configured to execute any of the methods provided by the present invention according to the obtained executable instructions, such as: receiving a random access sequence sent by a user terminal, wherein the random access sequence comprises a leader sequence and a label sequence;
synchronously completing timing detection of the leader sequence and collision detection of the label sequence based on the random access sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
It should be noted that, the device for network side collision detection provided by the present invention can implement all the method steps implemented by the method embodiment for collision detection, and can achieve the same technical effect, and detailed descriptions of the same parts and beneficial effects as those of the method embodiment in this embodiment are not repeated herein.
Fig. 9 is a schematic structural diagram of a user terminal collision detection device provided in the present invention, and as shown in fig. 9, the user terminal collision detection device includes a memory 920, a transceiver 910 and a processor 900; wherein the processor 900 and the memory 920 may also be physically separated.
A memory 920 for storing a computer program; a transceiver 910 for transceiving data under the control of the processor 900.
In particular, the transceiver 910 is used to receive and transmit data under the control of the processor 900.
In fig. 9, among other things, the bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 900, and various circuits, represented by memory 920, being linked together. The bus architecture may also link various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 910 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like. The user interface 930 may also be an interface capable of interfacing with a desired device for different user devices, including but not limited to a keypad, display, speaker, microphone, joystick, etc.
The processor 900 is responsible for managing the bus architecture and general processing, and the memory 920 may store data used by the processor 900 in performing operations.
The processor 900 may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or a Complex Programmable Logic Device (CPLD), and may also have a multi-core architecture.
The processor 900 is adapted to execute any of the methods provided by the present invention by calling the computer program stored in the memory 920 according to the obtained executable instructions, for example: sending a random access sequence, wherein the random access sequence comprises a leader sequence and a label sequence;
the random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
It should be noted that, the apparatus for detecting a user terminal conflict provided by the present invention can implement all the method steps implemented by the method embodiment for detecting a conflict, and can achieve the same technical effect, and detailed descriptions of the same parts and beneficial effects as the method embodiment in this embodiment are not repeated herein.
Fig. 10 is a schematic structural diagram of a collision detection apparatus provided in the present invention. As shown in fig. 10, the apparatus includes:
a receiving module 1001, configured to receive a random access sequence sent by a user equipment, where the random access sequence includes a preamble sequence and a tag sequence;
a detecting module 1002, configured to synchronously complete timing detection of the preamble sequence and collision detection of the tag sequence based on the random access sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
Optionally, the receiving user terminal sends a random access sequence, where the random access sequence includes a preamble sequence and a tag sequence, and includes:
indexing u based on physical root 2 And a tag index/, determining the tag sequence;
wherein the value range of the label index L is [0, L RA -1],L RA Is the length of the leader sequence.
Optionally, the synchronously completing timing detection of a preamble sequence and collision detection of a tag sequence based on the random access sequence includes:
based on a receiving end detection model, performing cross correlation on the random access sequence and a local root sequence to obtain a first power delay spectrum, and performing peak detection to complete timing detection of the leader sequence;
According to the timing detection of the leader sequence, determining the position of a peak value, the transmission delay and the physical root index of the leader sequence;
and determining the physical root index of the label sequence according to the physical root index of the leader sequence, performing cross-correlation on the random access sequence and the label root sequence to obtain a second power time delay spectrum, and performing peak value detection.
Optionally, the determining a physical root index of a tag sequence according to the physical root index of the preamble sequence, performing cross-correlation between the random access sequence and the tag root sequence to obtain a second power delay profile, and performing peak detection includes:
determining a physical root index of the tag sequence based on a co-prime relationship of the physical root index of the preamble sequence and the physical root index of the tag sequence;
and sending a notice to the user terminal if a plurality of conditions greater than the threshold exist according to the peak value comparison between the peak value detection result and the threshold.
Fig. 11 is a second schematic structural diagram of a collision detection apparatus provided in the present invention. As shown in fig. 11, the apparatus includes:
a sending module 1101, configured to send a random access sequence, where the random access sequence includes a preamble sequence and a tag sequence;
The random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
Optionally, the sending a random access sequence, where the random access sequence includes a preamble sequence and a tag sequence, includes:
indexing u based on physical root 2 And a tag index/, determining the tag sequence;
wherein the value range of the label index L is [0, L RA -1],L RA Is the length of the leader sequence.
It should be noted that the division of the unit in the present invention is schematic, and is only a logic function division, and there may be another division manner in actual implementation. In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.
The integrated unit, if implemented as a software functional unit and sold or used as a stand-alone product, may be stored in a processor readable storage medium. Based on such understanding, the technical solution of the present invention may substantially or partially contribute to the prior art, or all or part of the technical solution may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, a network device, or the like) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.
It should be noted that, the apparatus provided in the present invention can implement all the method steps implemented by the method embodiments and achieve the same technical effects, and detailed descriptions of the same parts and beneficial effects as the method embodiments in this embodiment are omitted here.
In another aspect, the present invention also provides a processor-readable storage medium, the processor-readable storage mediumThe medium stores a computer program for causing the processor to execute the method for detecting a conflict provided by the above embodiments, including: receiving a random access sequence sent by a user terminal, wherein the random access sequence comprises a leader sequence and a label sequence; synchronously completing timing detection of the leader sequence and collision detection of the label sequence based on the random access sequence; wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
In another aspect, the present invention further provides a processor-readable storage medium, where a computer program is stored, where the computer program is configured to cause a processor to execute the collision detection method provided in the foregoing embodiments, and the method includes: sending a random access sequence, wherein the random access sequence comprises a leader sequence and a label sequence; the random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence; wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 Are relatively prime.
The processor-readable storage medium can be any available medium or data storage device that can be accessed by a processor, including, but not limited to, magnetic memory (e.g., floppy disks, hard disks, magnetic tape, magneto-optical disks (MOs), etc.), optical memory (e.g., CDs, DVDs, BDs, HVDs, etc.), and semiconductor memory (e.g., ROMs, EPROMs, EEPROMs, non-volatile memory (NAND FLASH), Solid State Disks (SSDs)), etc.
As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, and the like) having computer-usable program code embodied therein.
The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer-executable instructions. These computer-executable instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the processor-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These processor-executable instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (9)

1. A method for collision detection is applied to a network side device, and includes:
receiving a random access sequence sent by a user terminal, wherein the random access sequence comprises a leader sequence and a label sequence;
synchronously completing timing detection of the leader sequence and collision detection of the label sequence based on the random access sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 The leader sequence and the tag sequence are both generated by cyclic shift of a ZC sequence;
the synchronous completion of the timing detection of the leader sequence and the collision detection of the tag sequence based on the random access sequence comprises the following steps:
based on a receiving end detection model, performing cross correlation on the random access sequence and a local root sequence to obtain a first power delay spectrum, and performing peak detection to complete timing detection of the leader sequence;
determining the position of a peak value, transmission delay and a physical root index of the leader sequence according to the timing detection result of the leader sequence;
determining a physical root index of a label sequence according to the physical root index of the leader sequence, performing cross-correlation on the random access sequence and the label sequence to obtain a second power time delay spectrum, and performing peak value detection;
Determining the physical root index of the label sequence according to the physical root index of the leader sequence, performing cross-correlation on the random access sequence and the label sequence to obtain a second power time delay spectrum, and performing peak detection, wherein the method comprises the following steps:
determining a physical root index of the tag sequence based on a co-prime relationship of the physical root index of the preamble sequence and the physical root index of the tag sequence;
and comparing the detection result of the peak value of the second power delay spectrum with a preset threshold peak value, and if a plurality of conditions greater than the threshold exist, sending a notice to the user terminal.
2. The method of claim 1, wherein the receiving a random access sequence sent by a user terminal, the random access sequence comprising a preamble sequence and a tag sequence comprises:
indexing u based on physical root 2 And a tag index/, determining the tag sequence;
wherein the value range of the label index L is [0, L RA -1],L RA Is the length of the leader sequence.
3. A method for collision detection is applied to a user terminal, and comprises the following steps:
sending a random access sequence, wherein the random access sequence comprises a leader sequence and a label sequence;
The random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 And the leader sequence and the tag sequence are both generated by cyclic shift of the ZC sequence.
4. The method of collision detection according to claim 3, wherein the sending a random access sequence, the random access sequence comprising a preamble sequence and a tag sequence, comprises:
indexing u based on physical root 2 And a tag index/, determining the tag sequence;
wherein the value range of the label index L is [0, L RA -1],L RA Is the length of the leader sequence.
5. A network side conflict detection device comprises a memory, a transceiver and a processor;
a memory for storing a computer program; a transceiver for transceiving data under control of the processor; a processor for executing the computer program in the memory and implementing the steps of:
receiving a random access sequence sent by a user terminal, wherein the random access sequence comprises a leader sequence and a label sequence;
synchronously completing timing detection of the leader sequence and collision detection of the label sequence based on the random access sequence;
Wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 The leader sequence and the tag sequence are both generated by cyclic shift of a ZC sequence;
the synchronous completion of the timing detection of the leader sequence and the collision detection of the tag sequence based on the random access sequence comprises the following steps:
based on a receiving end detection model, performing cross correlation on the random access sequence and a local root sequence to obtain a first power delay spectrum, and performing peak detection to complete timing detection of the leader sequence;
determining the position of a peak value, transmission delay and a physical root index of the leader sequence according to the timing detection result of the leader sequence;
determining a physical root index of a label sequence according to the physical root index of the leader sequence, performing cross-correlation on the random access sequence and the label sequence to obtain a second power time delay spectrum, and performing peak value detection;
determining the physical root index of the label sequence according to the physical root index of the leader sequence, performing cross-correlation on the random access sequence and the label sequence to obtain a second power time delay spectrum, and performing peak detection, wherein the method comprises the following steps:
determining a physical root index of the tag sequence based on a co-prime relationship of the physical root index of the preamble sequence and the physical root index of the tag sequence;
And comparing the detection result of the peak value of the second power delay spectrum with a preset threshold peak value, and if a plurality of conditions greater than the threshold exist, sending a notice to the user terminal.
6. A user terminal collision detection device comprises a memory, a transceiver, and a processor;
a memory for storing a computer program; a transceiver for transceiving data under control of the processor; a processor for executing the computer program in the memory and implementing the steps of:
sending a random access sequence, wherein the random access sequence comprises a leader sequence and a label sequence;
the random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 And the leader sequence and the tag sequence are both generated by cyclic shift of the ZC sequence.
7. An apparatus for collision detection, applied to a network side device, includes:
a receiving module, configured to receive a random access sequence sent by a user terminal, where the random access sequence includes a preamble sequence and a tag sequence;
A detection module, configured to synchronously complete timing detection of the preamble sequence and collision detection of the tag sequence based on the random access sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 The leader sequence and the tag sequence are both generated by cyclic shift of a ZC sequence;
the detection module is further configured to:
based on a receiving end detection model, performing cross correlation on the random access sequence and a local root sequence to obtain a first power delay spectrum, and performing peak detection to complete timing detection of the leader sequence;
determining the position of a peak value, transmission delay and a physical root index of the leader sequence according to the timing detection result of the leader sequence;
determining a physical root index of a label sequence according to the physical root index of the leader sequence, performing cross-correlation on the random access sequence and the label sequence to obtain a second power time delay spectrum, and performing peak value detection;
determining the physical root index of the label sequence according to the physical root index of the leader sequence, performing cross-correlation on the random access sequence and the label sequence to obtain a second power time delay spectrum, and performing peak detection, wherein the method comprises the following steps:
Determining a physical root index of the tag sequence based on a co-prime relationship of the physical root index of the preamble sequence and the physical root index of the tag sequence;
and comparing the detection result of the peak value of the second power delay spectrum with a preset threshold peak value, and if a plurality of conditions greater than the threshold exist, sending a notice to the user terminal.
8. An apparatus for collision detection, applied to a user terminal, includes:
a sending module, configured to send a random access sequence, where the random access sequence includes a preamble sequence and a tag sequence;
the random access sequence is used for the network side equipment to synchronously complete the timing detection of the leader sequence and the collision detection of the label sequence;
wherein a physical root index u of the preamble sequence 1 And a physical root index u of the tag sequence 2 And the leader sequence and the tag sequence are both generated by cyclic shift of the ZC sequence.
9. A processor-readable storage medium, characterized in that the processor-readable storage medium stores a computer program for causing a processor to perform the method of collision detection of any one of claims 1 to 2, or the method of collision detection of any one of claims 3 to 4.
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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112752351A (en) * 2019-10-31 2021-05-04 华为技术有限公司 Method and communication device for sequence-based signal transmission

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
An Early Preamble Collision Detection Scheme Based on Tagged Preambles for Cellular M2M Random Access;Han Seung Jang et al.;《IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY》;20170731;第66卷(第7期);第1-3节 *
长期演进系统中随机接入信号的产生方法;雷舒培 等;《计算机工程》;20110731;第37卷(第13期);全文 *

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