CN109743139A - Method based on PDCCH blind examination in 5G car networking D2D communication - Google Patents

Abstract

The invention discloses a kind of methods based on PDCCH blind examination in 5G car networking D2D communication, are related to wireless communication technology field.This method includes: 1. to extract the CCE information of PDCCH；2. solving the circulation biasing of cell；3. deinterleaving；4. the soft demodulation of QPSK；5. descrambling；6. power detection filtering algorithm；7. PDCCH blind examination and the screening of Candidate Set information)；8. the duplicate removal filtering algorithm of RNTI；9. sort algorithm of the RNTI based on PRIORITY；10. sort algorithm of the RNTI based on Metrics value.The present invention can be in the unknown UE RNTI information of reception terminal, and under conditions of middle high s/n ratio, effective blind examination goes out the RNTI information and DCI information of all public informations and all users in cell coverage area；It can be improved the analyzing efficiency of entire 5G system UE terminal physical layer downlink, there is very strong practicability.

Description

Method based on PDCCH blind examination in 5G car networking D2D communication

Technical field

The present invention relates to wireless communication technology fields, more particularly to one kind is based on PDCCH blind examination in 5G car networking D2D communication Method, for solving 5G car networking mobile terminal under conditions of unknown radio network temporary identifier RNTI, to PDCCH carry out The problem of blind examination.

Background technique

With the rapid development of wireless mobile communications business, demand of the people to wireless frequency spectrum business is constantly promoted, limited Frequency spectrum resource can no longer meet the business demand of 5G mass users under various circumstances, the availability of frequency spectrum is anxious wait improve.And Centered on base station, the position of base station (access point or relay station) is relatively fixed for traditional cellular communication, is a kind of fixed bee The MPS process of nest, in this traditional network architecture, Cell Edge User is more despite the use of since base station location is fixed Point cooperation technology can improve the covering performance of edge customer, but user's overall experience is poor always.5G system changes Mode centered on base station changes customer-centric, and wherein the crucial candidate technologies D2D of 5G communicates (Device-to- Device, D2D) can be realized without base station in the case where, realize terminal user between direct communication, be a kind of short distance number According to transmission technology, D2D communication is with community user shared resource under the control of cell base station, therefore the availability of frequency spectrum is mentioned It rises.D2D system under 5G network actually still continues to use existing cellular architecture in control plane, i.e., relevant control signaling, such as nothing Line resource allocation, authentication, mobile management etc. are still responsible for by cellular network；The data surface of D2D can be carried out directly between the terminals Transmission, does not need to forward by base station.

After 5G system introduces D2D communication, since data are directly transmitted between the terminals, to alleviate base station pressure, promoted Message transmission rate；Since D2D directly transmits data in terminal time, to reduce propagation delay time end to end, terminal is reduced Transmission power；Since widely distributed terminal is utilized in D2D, covering can be improved, coverage area is expanded, work as wireless communication infrastructure Facility damage, or in the coverage hole of wireless network, terminal can realize that end-to-end communication even accesses Cellular Networks by D2D Network promotes link flexibility and network reliability.In 5G network, authorization frequency spectrum is can be used in D2D communication, it is possible to use non-to award Weigh frequency spectrum；Can be using broadcast, multicast and unicast technique, it can also be with relaying technique (Relay), multi-antenna technology (Massive MIMO it) is combined with combined coding technology etc., bigger performance boost is carried out to 5G Netowrk tape.

On the other hand, the development of contemporary traffic system has been increasingly becoming human society and has rely flourishing foundation.In the past Decades between, Urbanization in China accelerate, automobile quantity constantly increases, while technological innovation constantly promotes traffic system Performance and efficiency.Internet of Things, which is applied to intelligent transportation field, boundless prospect, and this application is presented as vehicle Networking.Foundation technology of the car networking communication as the following intelligent transportation system, by more and more extensive concern.Car networking is V2X is the entity communication in automobile and other base station networks, including Vehicle-to-infrastructure(V2I), Vehicle-to-vehicle(V2V), Vehicle-to-Pedestrian(V2P), Vehicle-to-Network (V2N). Car networking business can be divided into three classes: security classes, info class and traffic efficiency class.Security classes application is to prevent automobile from traffic occurs Accident, info class are that the information service of road construction one kind is provided for automobile, and traffic efficiency class is electronic traffic signal, green wave band one The application of class promotion traffic efficiency.Wherein, security classes business can reduce traffic accident, be mostly important.Car networking V2X can To be defined as a kind of means for obtaining other vehicles, pedestrian's driving status (speed, brake, lane change).As of greatest concern Vertical industry application, the model that car networking has very big chance to become communications industry and conventionally manufactured industry cooperation.

In existing car networking, the problems such as that there are time delays is big for information exchange, low rate.And the D2D technology in 5G communication Have many advantages, such as low time delay, high capacity, high-speed, low energy consumption, the problems being able to solve in car networking.D2D communication is not required to Fully controlling for base station is wanted, base station only provides necessary and a small amount of auxiliary information and D2D terminal is helped to carry out autonomous communication, due to D2D is communicated in Reusespectrum resource, it is necessary to know the resource allocation conditions of all terminals in base station cell.This needs blind examination Control information in PDCCH obtains local resource and distributes information.Then D2D terminal can pass through own radio resource Management algorithm selects the band resource that can be multiplexed, and completes the mutual direct communication of D2D terminal, and guarantees its communication pair In base station or other cell terminals interference in its acceptable range.Since D2D communication is not over the tune of base station Degree, so D2D terminal is not aware that the quantity of all terminals in cell, do not know yet their own RNTI or it is other more Multi information.So can only be carried out in the case where unknown RNTI blind when monitoring base station broadcast, parsing PDCCH information Decoding, and the protocol rule based on some settings carries out probability analysis to the signal received, also, enough in data volume In the case of, it is considered as the practical position DCI that the maximum Candidate Set of possibility is exactly some UE.

Patent CN 107911200A(denomination of invention: the implementation method of LTE system PDCCH blind examination) in consider equipment room The scene of direct communication (Device-to-Device, D2D) proposes under conditions of unknown RNTI, the method for PDCCH blind examination. Its key technology are as follows: 1. obtained in public search space and user's dedicated search space by exclusive or division and be implicitly included in CRC The method of the RNTI information of middle carrying；2. the screening technique in user's dedicated search space: the traversal all possible candidate of PDDCH Collection after getting RNTI information by exclusive or division, calculates the start position of Candidate Set CCE according to RNTI, and with reality The initial position of CCE is compared, and the PDDCH Candidate Set is abandoned if not identical, if the same retains PDDCH candidate The method of collection；3. by the path metric value Metrics of every group of PDDCH Candidate Set Viterbi decoding to reservation from high to low into The sequence of row major grade, and the method for carrying out collision screening.

Summary of the invention

The purpose of the present invention is the demands for 5G car networking D2D communication, provide a kind of based in 5G car networking D2D communication The method of PDCCH blind examination can detect that public message in cell coverage area and institute are useful in the case where unknown RNTI RNTI the and DCI information at family.

The object of the present invention is achieved like this:

This method has expanded two kinds of sides on the basis of patent CN 107911200A, from the angle of power detection and RNTI duplicate removal Method can more efficiently detect all existing public messages in cell coverage area in the environment of middle high s/n ratio With RNTI the and DCI information of all users；Meanwhile this method can also improve entire 5G system UE terminal physical layer downlink Analyzing efficiency.

This method be different from conventional LTE system can only in situation known to RNTI, for a certain particular UE terminal into The method of row PDCCH blind examination can detect that cell is covered in the case where unknown RNTI, in the environment of middle high s/n ratio RNTI the and DCI information of public message and all users within the scope of lid.

Specifically, this method the following steps are included:

1. extracting the CCE information of PDCCH

The control domain of PDCCH is indicated according to PCFICH, extracts OFDM symbol CCE information, and calculate CCE number for being used for PDCCH；

2. solving the circulation biasing of cell；

3. deinterleaving；

4. the soft demodulation of QPSK；

5. descrambling；

6. power detection filtering algorithm

Go out the PDCCH Candidate Set of all possibility users under the base station cell by power detection algorithm preliminary screening, and saves institute There are the parameter information of the starting of PDCCH Candidate Set CCE, end position and polymerization grade L；

7. the PDCCH Candidate Set information of PDCCH blind examination and all possible users of the screening of Candidate Set information, pass through patent CN The screening technique of 107911200A description carries out further screening operation, and save the PDDCH Candidate Set user RNTI, The path metric value Metrics value of the starting of CCE and final position and Viterbi decoding；

8. the duplicate removal filtering algorithm of RNTI

It may filter that the PDCCH Candidate Set information that RNTI is repeated under the cell by the Duplicate Removal Algorithm of RNTI；

9. sort algorithm of the RNTI based on PRIORITY

Sort algorithm by RNTI based on PRIORITY can filter out the higher PDCCH Candidate Set letter of authenticity under the cell Breath；

10. sort algorithm of the RNTI based on Metrics value

Sort algorithm by RNTI based on Metrics value, can filter out PRIORITY under the cell is 0, and authenticity is higher PDCCH Candidate Set information.

The key technology of PDCCH blind examination implementation method provided by the invention is:

1, apply step 6. in, by power detection algorithm filter out under the cell it is all possibility users PDCCH Candidate Set Method；

2, apply step 8. 9. 10. in, by the Duplicate Removal Algorithm of RNTI, the sort algorithm based on PRIORITY and be based on The method that the sort algorithm of Metrics value filters out the PDCCH Candidate Set information of eventually possible user under the cell.

The present invention has following advantages and good effect:

1. can be in the unknown UE RNTI information of reception terminal, under conditions of middle high s/n ratio, effective blind examination goes out MPS process The RNTI information and DCI information of all public informations and all users in range；

2. can be improved the analyzing efficiency of entire 5G system UE terminal physical layer downlink, there is very strong practicability.

Detailed description of the invention

Fig. 1 is the general flow chart of this method；

Fig. 2 is to determine the flow chart of noise and useful signal thresholding in the data information that PDCCH is deinterleaved；

Fig. 3 is the flow chart of power detection filtering algorithm；

Fig. 4 is the flow chart of the duplicate removal filtering algorithm of RNTI；

Fig. 5 is the flow chart of PDCCH Candidate Set PRIORITY prioritizing algorithm；

Fig. 6 is the flow chart for the algorithm that PDCCH Candidate Set is ranked up based on the height of Metrics value.

English to Chinese

1, LTE:Long Term Evolution, long term evolution；

2,5G:Fifth-generation, the 5th generation communication technology；

3, UE:User Equipment, user equipment；

4, OFDM:Orthogonal Frequency Division Multiplexing, orthogonal frequency division multiple access；

5, RNTI:Radio Network Temporary identifier, radio network temporary identifier；

6, PBCH:Physical Broadcast Channel controls information physical broadcast channel；

7, PCFICH:Physical Control Format Indicator Channel, Physical Control Format Indicator Channel；

8, PHICH: Physical Hybrid ARQ Indicator Channel, physical mixed automatic re-transmission indicating channel；

9, PDCCH:Physical Downlink Control Channel, Physical Downlink Control Channel；

10, CCE:, Control Channel Element, control channel unit；

11, DCI:Downlink Control Information, Downlink Control Information；

12, CRC:Cyclic Redundancy Check, cyclic redundancy check.

Specific embodiment

The implementation detail of this method is further described with reference to the accompanying drawing.

One, the applicable scene of the present invention

In the case where unknown UE number and unknown RNTI；MPS process under the conditions of middle high s/n ratio (being greater than 15dB)；It is typical Using in 5G car networking D2D communication, D2D terminal is not aware that the quantity of all terminals in cell, does not also know each RNTI or other more information, can only be carried out in the case where unknown RNTI it is blind solution PDCCH information scene.

Two, method

Such as Fig. 1, this method includes the following steps:

1. extracting the CCE information -101 of PDCCH；

2. solving the circulation biasing -102 of cell；

3. deinterleaving -103；

4. the soft demodulation -104 of QPSK；

5. descrambling -105；

6. power detection filtering algorithm -106；

7. PDCCH blind examination and the screening -107 of Candidate Set information；

8. the duplicate removal filtering algorithm -108 of RNTI；

9. sort algorithm -109 of the RNTI based on PRIORITY；

10. sort algorithm -110 of the RNTI based on Metrics value.

Three, related step

1,1. step extracts PDCCH CCE information -101

The control domain of PDCCH is indicated according to PCFICH, extracts OFDM symbol CCE information, and calculates of the CCE for PDCCH Number；

CCE number extracting method is similar with conventional blind detection method, the symbol numbers that PDCCH is occupied in a subframe in LTE, It is determined by the CFI as defined in PCFICH；In the occupied symbol of PDCCH, in addition to PDCCH, also include PCFICH, The content of PHICH and RS；Wherein the content of PCFICH is demodulated, and the distribution of PHICH is determined by PBCH, and the distribution of RS depends on The antenna port number broadcasted in PBCH；Therefore, the CCE number that PDCCH is occupied in a subframe determines that.

2, step 6. power detection filtering algorithm -106

Power detection filtering algorithm is as follows:

A, firstly, 3. deinterleaving -103 data information according to step using RE as linear module, noise and useful signal are determined Thresholding；PDCCH RE total number is set as X, the total number of CCE is Y, then Z=X-36*Y, and the corresponding value of Z is PDCCH tail part Number；If Z is greater than 0, the power maximum value of PDCCH tail partial data is set as to the thresholding of noise and useful signal； If Z is equal to 0, the power of the average value of all data of PDCCH is set as to the thresholding of noise and useful signal；

Such as Fig. 2, determine that the process of noise and useful signal thresholding is as follows:

A, start -201；

B, the total number X of PDCCH RE is obtained；Obtain the total number Y of PDCCH CCE；Obtain the number Z of PDCCH tail part RE =X-36*Y-202；

C, judge whether the number Z of PDCCH tail part RE is greater than 0-203, be to enter step d, otherwise own PDCCH The power of the average value of data jumps to step f after being set as the thresholding -205 of noise and useful signal again；

D, the power maximum value of PDCCH tail partial data is set as to the thresholding -204 of noise and useful signal；

E, terminate -206.

B, then, judge by all data informations of the threshold values to deinterleaving of the thresholding, be then if it is greater than threshold values 1, it is then 0 if it is less than threshold values, and by the data information memory in array M [MAX_RE_LENGTH]；Wherein, MAX_RE_ LENGTH is the length of data information after deinterleaving, and is regular length；

C, then, array M is recombinated as unit of CCE, due to 1CCE=36RE, one-dimension array M is converted into two dimension Every 36 data of array N [36] [MAX_RE_LENGTH/36], array N are a complete CCE information, theoretically effectively 36 RE values of 1 CCE of signal should be equal to 1, but consider actual conditions, we set the number of RE in 1 CCE In 32~36 range, and do not require continuous；That is: if the number of RE is greater than or equal to 32 in 1 CCE, then it is assumed that this CCE is useful signal, and the value of the CCE is set as 1；If the number of RE is less than 32 in 1 CCE, then it is assumed that this CCE For invalid signals, and the value of the CCE is set as 0；Judging result information is stored in array N_CCE [MAX_RE_ by us LENGTH/36]；

D, finally, being that 1,2,4,8 sequences begin stepping through all PDCCH Candidate Sets in entire search space according to polymerization grade L, Including public search space (Y_k0) and user's dedicated search space for；Since the information of DCI is continuously, to occupy CCE number must all continuously be 1, CCE starting and terminal if meeting the condition by the PDCCH Candidate Set, Yi Jiju The information preservation for closing grade L is got off.

Workflow such as Fig. 3, power detection filtering algorithm is as follows:

A, start -301；

B, the total number -302 of the entire search space current candidate collection Ncce of PDCCH is obtained；

C, according to deinterleaved data information using RE as linear module, the thresholding -303 of noise and useful signal is determined；

D, judge by all data informations of the threshold values to deinterleaving of the thresholding, be then 1 if it is greater than threshold values, if it is less than Threshold values is then 0, and by the data information memory in array M-304；

E, array M is recombinated and is screened as unit of CCE, determine PDCCH currently possible Candidate Set -305；

F, all PDDCH Candidate Sets in entire search space are begun stepping through, X is set and assigns initial value as 1, polymerization grade L=2^Y, if Determine Y to assign initial value to be 3；-306；

G, judge whether Y value is greater than or equal to 0-307, be, enter step h, otherwise process terminates -314；

H, judge whether X value is less than floor (Ncce/L) -308, be to enter step i, (Y -1) is otherwise assigned to Y-309 Jump to step g again afterwards；

I, the starting point start of CCE is equal to ((x-1) * L+1), and the terminal end of CCE is equal to (start+L-1) -310；

J, judge that the corresponding value of the origin-to-destination of CCE whether continuously for 1-311, is to enter step k, otherwise assigns (X+1) It is worth to jumping to step h after X-312 again；

K, the RNTI value and relevant information -313 of this group of PDDCH Candidate Set user are saved, and passes through and (X+1) is assigned to X-312 Jump to step h again afterwards.

3, step 7. PDCCH blind examination and the screening -107 of Candidate Set information

The PDCCH of all possibility users under the cell is 6. filtered out according to the PDCCH data information after descrambling and by step Candidate Set information carries out further screening operation by the screening technique of patent CN 107911200A description, and saving should The path metric value of the starting of RNTI, CCE of all PDDCH Candidate Set users and final position and Viterbi decoding under cell Metrics value.

4, the duplicate removal filtering algorithm -108 of step 8. RNTI

In 7. PDCCH Candidate Set that step screens, the PDCCH Candidate Set of different polymerization grade L, different search spaces can It can generate identical RNTI, it is therefore desirable to the duplicate removal filtering algorithm for considering RNTI sets PDCCH Candidate Set total number as K, time Some Candidate Set gone through is PDCCH [i] (i=1 ~ K), set the priority P RIORITY initial values of all PDCCH Candidate Sets as 0, detailed process is as follows:

All PDCCH Candidate Sets are traversed, whether the RNTI value for comparing PDCCH [i] and PDCCH [i+1] is identical, if identical, Then to the RNTI value tax 0 of PDCCH [i+1], meanwhile, the priority P RIORITY of PDCCH [i] is added 1；Subsequently into next time Circulation, until having traversed all PDCCH Candidate Sets.

Process such as Fig. 4, the duplicate removal filtering algorithm of RNTI is as follows:

A, start -401；

B, it is 1-402 that i, which assigns initial value,；

C, judge whether the RNTI of the RNTI and PDCCH [i+1] of PDCCH [i] equal, and RNTI value is not 0-403, be then into Enter step d, otherwise continues step c from after increasing 1-406 by i value；

D, the priority that the RNTI value of PDCCH [i+1] assigns 0, PDCCH [i] increases 1 certainly, while i value increases 1-404 certainly；

E, PDCCH Candidate Set total number is set as K, judges whether i value is less than (K-1) -405, is, is entered step f, is otherwise turned To step c；

F, terminate -407.

5, step 9. sort algorithm -109 of the RNTI based on PRIORITY；

In the PDCCH Candidate Set mentioned above screened, the PDCCH Candidate Set of different polymerization grade L, different search spaces can It can generate identical RNTI.Simultaneously as such PDCCH Candidate Set occurred repeatedly repeatedly, and therefore, the PDCCH Candidate Set Authenticity also greatly improve, it is necessary to drop it into front go to decode；

PDCCH Candidate Set PRIORITY prioritizing algorithm: traversing all PDCCH Candidate Sets, compare PDCCH [i] and The priority P RIORITY of PDCCH [i+1], if the priority P RIORITY of PDCCH [i] is less than PDCCH [i+1], meanwhile, In the case that the RNTI value of PDCCH [i] and PDCCH [i+1] are not 0, then by PDCCH [i] and PDCCH [i+1] all letters Breath exchanges；Subsequently into recycling next time, until having traversed all PDCCH Candidate Sets；In this manner it is ensured that priority is high PDCCH Candidate Set can be decoded preferentially；

Process such as Fig. 5, PDCCH Candidate Set prioritizing algorithm is as follows:

A, start -501；

B, it is 1-502 that i, which assigns initial value,；

C, judge whether the priority of PDCCH [i] is less than the priority of PDCCH [i+1], and the RNTI of PDCCH [i] and The RNTI value of PDCCH [i+1] is not 0-503, is to enter step d, is otherwise further continued for step from after increasing 1-506 by i value c；

D, the value of PDCCH [i] and PDCCH [i+1] exchange -504；

E, PDCCH Candidate Set total number is set as K, judges whether i value is less than (K-1) -505, is, increases 1-506 certainly by i value It jumps to step c again afterwards, otherwise enters step f；

F, terminate -507.

6, step 10. sort algorithm -110 of the RNTI based on Metrics value；

Traverse all PDCCH Candidate Sets, by all priority P RIORITY be 0 PDCCH Candidate Set according to Metrics value Height is ranked up, and compares the Metrics value of PDCCH [i] and PDCCH [i+1], if the Metrics value of PDCCH [i] is small In PDCCH [i+1], then by PDCCH [i] and PDCCH [i+1] all information exchanges；Subsequently into recycling next time, until time All PDCCH Candidate Sets are gone through.

Such as Fig. 6, PDCCH Candidate Set is as follows according to the algorithm flow that the height of Metrics value is ranked up:

A, start -601；

B, it is 1-602 that i, which assigns initial value,；

C, judge whether the Metrics of PDCCH [i] is less than the Metrics of PDCCH [i+1], and the PRIORITY of PDCCH [i] PRIORITY with PDCCH [i+1] is 0-603, is to enter step d, otherwise continues step from after increasing 1-606 by i value c；

D, the value of PDCCH [i] and PDCCH [i+1] exchange -604；

E, PDCCH Candidate Set total number is set as K, judges whether i value is less than (K-1) -605, is, increases 1-606 certainly by i value After jump to step c, otherwise enter step f；

F, terminate -607.

Claims (6)

1. the method based on PDCCH blind examination in 5G car networking D2D communication, it is characterised in that:

1. extracting the CCE information (101) of PDCCH

The control domain of PDCCH is indicated according to PCFICH, extracts OFDM symbol CCE information, and calculate CCE number for being used for PDCCH；

2. the circulation for solving cell biases (102)；

3. deinterleaving (103)；

4. the soft demodulation (104) of QPSK；

5. descrambling (105)；

6. power detection filtering algorithm (106)

Go out the PDCCH Candidate Set of all possibility users under the base station cell by power detection algorithm preliminary screening, and saves institute There are the parameter information of the starting of PDCCH Candidate Set CCE, end position and polymerization grade L；

7. PDCCH blind examination and the screening of Candidate Set information (107)

The PDCCH of all possibility users under the cell is 6. filtered out according to the PDCCH data information after descrambling and by step Candidate Set information carries out further screening operation by the screening technique of patent CN 107911200A description, and saving should The path metric value Metrics value of the starting of RNTI, CCE of PDDCH Candidate Set user and final position and Viterbi decoding；

8. the duplicate removal filtering algorithm (108) of RNTI

It may filter that the PDCCH Candidate Set information that RNTI is repeated under the cell by the Duplicate Removal Algorithm of RNTI；

9. sort algorithm (109) of the RNTI based on PRIORITY

Sort algorithm by RNTI based on PRIORITY can filter out the higher PDCCH Candidate Set letter of authenticity under the cell Breath；

10. sort algorithm (110) of the RNTI based on Metrics value

Sort algorithm by RNTI based on Metrics value, can filter out PRIORITY under the cell is 0, and authenticity is higher PDCCH Candidate Set information.

2. the method according to claim 1 based on PDCCH blind examination in 5G car networking D2D communication, it is characterised in that:

Determine that the process of noise and useful signal thresholding is as follows:

A, start (201)；

B, the total number X of PDCCH RE is obtained；Obtain the total number Y of PDCCH CCE；Obtain the number Z of PDCCH tail part RE =X-36*Y(202)；

C, judge whether the number Z of PDCCH tail part RE is greater than 0(203), it is to enter step d, otherwise owns PDCCH The power of the average value of data jumps to step f after being set as the thresholding (205) of noise and useful signal again；

D, the power maximum value of PDCCH tail partial data is set as to the thresholding (204) of noise and useful signal；

E, terminate (206).

3. the method according to claim 1 based on PDCCH blind examination in 5G car networking D2D communication, it is characterised in that:

The workflow of power detection filtering algorithm is as follows:

A, start (301)；

B, the total number (302) of the entire search space current candidate collection Ncce of PDCCH is obtained；

C, according to deinterleaved data information using RE as linear module, the thresholding (303) of noise and useful signal is determined；

D, judge by all data informations of the threshold values to deinterleaving of the thresholding, be then 1 if it is greater than threshold values, if it is less than Threshold values is then 0, and by the data information memory in array M(304)；

E, array M is recombinated and is screened as unit of CCE, determine PDCCH currently possible Candidate Set (305)；

F, all PDDCH Candidate Sets in entire search space are begun stepping through, X is set and assigns initial value as 1, polymerization grade L=2^Y, if Determine Y to assign initial value to be 3(306)；

G, judge whether Y value is greater than or equal to 0(307), it is to enter step h, otherwise process terminates (314)；

H, judge whether X value is less than floor (Ncce/L) (308), be to enter step i, (Y -1) is otherwise assigned to Y (309) step g is jumped to after again；

I, the starting point start of CCE is equal to ((x-1) * L+1), and the terminal end of CCE is equal to (start+L-1) (310)；

J, judge whether the corresponding value of the origin-to-destination of CCE is continuous for 1(311), is to enter step k, otherwise by (X+1) Be assigned to X(312) after jump to step h again；

K, the RNTI value and relevant information -313 of this group of PDDCH Candidate Set user are saved, and passes through and (X+1) is assigned to X-312 Jump to step h again afterwards.

4. the method according to claim 1 based on PDCCH blind examination in 5G car networking D2D communication, it is characterised in that:

The process of the duplicate removal filtering algorithm of RNTI is as follows:

A, start (401)；

B, it is 1(402 that i, which assigns initial value)；

C, judge whether the RNTI of the RNTI and PDCCH [i+1] of PDCCH [i] are equal, and RNTI value is not 0(403), it is then D is entered step, otherwise by i value from increasing 1(406) after continue step c；

D, the priority that the RNTI value of PDCCH [i+1] assigns 0, PDCCH [i] increases 1 certainly, while i value increases 1(404 certainly)；

E, PDCCH Candidate Set total number is set as K, judges whether i value is less than (K-1) (405), is to enter step f, is otherwise turned To step c；

F, terminate (407).

5. the method according to claim 1 based on PDCCH blind examination in 5G car networking D2D communication, it is characterised in that:

The process of PDCCH Candidate Set prioritizing algorithm is as follows:

A, start (501)；

B, it is 1(502 that i, which assigns initial value)；

C, judge whether the priority of PDCCH [i] is less than the priority of PDCCH [i+1], and the RNTI of PDCCH [i] and The RNTI value of PDCCH [i+1] is not 0(503), be to enter step d, otherwise by i value, oneself increases 1(506) after be further continued for walking Rapid c；

D, the value of PDCCH [i] and PDCCH [i+1] exchange (504)；

E, PDCCH Candidate Set total number is set as K, judges whether i value is less than (K-1) (505), is then to increase 1 certainly by i value (506) step c is jumped to after again, otherwise enters step f；

F, terminate (507).

6. the method according to claim 1 based on PDCCH blind examination in 5G car networking D2D communication, it is characterised in that:

PDCCH Candidate Set is as follows according to the algorithm flow that the height of Metrics value is ranked up:

A, start (601)；

B, it is 1(602 that i, which assigns initial value)；

C, judge whether the Metrics of PDCCH [i] is less than the Metrics of PDCCH [i+1], and the PRIORITY of PDCCH [i] PRIORITY with PDCCH [i+1] is 0(603), be to enter step d, otherwise by i value from increasing 1(606) after continue to walk Rapid c；

D, the value of PDCCH [i] and PDCCH [i+1] exchange (604)；

E, PDCCH Candidate Set total number is set as K, judges whether i value is less than (K-1) (605), is, increases 1-606 certainly by i value After jump to step c, otherwise enter step f；

F, terminate (607).