Patent ID: 11930080
Assignee: HUNAN UNIVERSITY
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 3:
4. The vehicle-mounted heterogeneous network collaborative task unloading method based on smart lamp posts according to claim 1, wherein the step S3 specifically comprises the following steps:
S31: calculating a communication delay Dijkn[t] of a vehicle i from a smart lamp post kn request to a cache j, wherein the calculation process is expressed as Dijkn[t]=Di(t)+Dq[t]: in the formula, Di(t) is a communication time of the cache j and Dq[t] is a queuing delay of the cache j;
wherein, Dj(t)=a(dik1[t]+dk1k2[t]+ . . . +dkn−1kn[t]), in the formula, dik1[t] represents a distance between the vehicle i and the nearest smart lamp post k1, dk1k2 represents a distance between the smart lamp post k1 and an adjacent smart lamp post k2, and dkn−1kn represents a distance between the smart lamp post kn−1 and a smart lamp post kn having the cache j; and a represents a communication constant, and is preset according to a channel condition;
wherein,, D
     q
    
    [
    t
    ]
   
   =
   
    
     
      g
      j
     
     (
     t
     )
    
    ⁢
    
     1
     
      
       E
       
        k
        n
       
      
      -
      
       
        ∑
        
          
         
          j
          ∈
          𝒩
         
        
       
       
        
         r
         j
        
        (
        t
        )
       
      
     
    
   
  
  ,, in the formula, gi(t) is a communication weight of the cache j and Ekn is the maximum number of vehicles that can be served by the smart lamp post kn; N is the total type of cache; and rj(t) is a number of vehicles served by the cache j on the smart lamp post kn at time t;
S32: traversing all the caches required for unloading a vehicle i task, taking the maximum communication delay in all the caches as the communication delay of the vehicle i, and taking the maximum communication delay in all the caches as the communication delay between the vehicle i and the smart lamp post network, and determining whether the communication delay between the vehicle i and the smart lamp post network is less than the time when the vehicle i sends a request to the cloud center, if so, the vehicle i unloads the task to the smart lamp post, otherwise, unloads the task to the cloud center; and
S33: dynamically adjusting a cache configuration of the smart lamp post within the communication range of each vehicle, and when the communication delay Dijkn[t] of the cache j is greater than the time requested from the cloud center, unloading the cache j on the smart lamp post, and reloading one of the cache groups requested from the cloud center by the vehicle.