34 results about "Maximal independent set" patented technology

The objective of the invention is to provide a method for post-routing redundant via insertion. The method is to construct a conflict graph from a post-routing design first, to find a maximal independent set (MIS) of the conflict graph, and to replace a single via with a double via for each vertex in the maximal independent set. Furthermore, since redundant vias can be classified into on-track and off-track ones and since on-track ones have better electrical properties, the invention also presents two methods to increase the amount of on-track redundant vias while a redundant via insertion solution is given.

Example embodiments disclosed herein relate to the determination of maximal independent sets (MISs) of mobile devices. Example embodiments include participating with other mobile devices of a plurality of mobile devices in concurrent distributed determinations of a plurality of MISs of the mobile devices and selecting one of the plurality of MISs.

A method allocates resources in an orthogonal frequency-division multiple access (OFDMA) network including a set of base stations (BSs), and a set of mobile stations (MSs) for each BS. Each cell includes a center and edge zone. A node weighted constraint graph is constructed for the network. Maximal independent sets in the graph are searched as sub-channels are allocated to the MSs in edge zones. Remaining bandwidth is allocated to the MSs in the center zones. Power is assigned to the sub-channels so that inter-cell interference is minimized and traffic load is maximized.

The invention discloses a graph theory based multi-cell two-layer network spectrum allocation method. According to the method based on a multi-cell scene in long term evolution (LTE), a macro base station and a family base station coexist and share a platform of a frequency spectrum, a maximum independent set of a graph is obtained by a genetic algorithm, and the frequency spectrum is distributed for macro users to obtain a resource block proportion occupied by the macro users. The macro base stations on different resource blocks and small-scale fading have influence on family users, so that a plurality of interference patterns are established, and a good scheme dynamic allocation frequency spectrum is provided. The method has the advantages that the cross-layer interference and co-layer interference are reduced, the requirement of service quality of the macro users can be met, the total handling capacity of a system is increased, and the compromise between the handling capacity of edge family users and the total handling capacity of the family users is achieved.

The present invention relates to the technical field of wireless mesh (Mesh) networks, in particular to a method for solving a conflict-free node set of a wireless mesh network, comprising steps: S1: establishing a conflict graph model G(V,E) of a wireless mesh network; S2: Select the node set S of the conflict graph model G(V,E) that does not conflict with node A A , then the node set S3 that conflicts with node A: Obtain all maximal independent sets T including node A of the conflict graph model G(V,E) A ; S4: Obtain the union of all maximal independent sets including each node in the node set S5: Obtain all the maximal independent sets, that is, the conflict-free node set. The method of the present invention establishes a 4D conflict graph model , and based on the Hasse graph traversal method to obtain all the maximum independent sets of the 4D conflict graph model, that is, the conflict-free node set, which is much simpler than the existing method of traversing all feasible combinations to obtain all maximum independent sets.

The invention discloses a resource exchange-based spatial information network task planning method, comprising the following steps: 1) initializing the basic parameters of the spatial information network; 2) dividing the planning period into K time slots of equal length, wherein each time slot The length of the gap is τ, and the time-varying graph G of spatial information network resources is constructed K (V,A); 3) For each task om i The feasible resource combination space of ∈OM is sampled, and the resource combination set P with independence greater than or equal to n i As a set of alternative resources; 4) Calculate the conflict relationship between each resource combination, and construct a resource combination conflict graph RCG(P C ,E C ); 5) Solve the maximum independent set in the resource combination conflict graph to obtain the global planning result; 6) Search the neighborhood of the global planning result, and then complete the local adjustment of the task planning scheme through resource exchange, and complete the resource-based Mission planning with interchangeable features, this method can reduce the computational complexity of mission planning while improving the mission completion rate.

The invention discloses a centralized link scheduling method for a multi-channel wireless network. The method comprises the following steps of: 1, numbering links in a network topology based on a wireless network topology consisting of n links, recording the number as 1,2, ..., and n and acquiring a corresponding network conflict graph G through the network topology; 2, acquiring a maximum independent set sequence Iseq of the network conflict graph according to the network conflict graph G in the step 1; and 3, acquiring a maximum group sequence Cseq of the network conflict graph according to the network conflict graph G in the step 1, recording number of elements in the maximum group sequence Cseq as m, wherein each element in the sequence corresponds to a maximum group, and numbering the elements according to a sequence from 1 to m to be recorded as Ci, wherein i is more than and equal to 1 and less than or equal to m. The centralized link scheduling method utilizes space diversity to the greatest degree, maximizes links which are transmitted simultaneously, improves the network capacity and is a conflict-free link scheduling method.

A channel allocation method based on mobility prediction in a cognitive radio network relates to a channel allocation technology in a cognitive radio technology in a communication system. It is to solve the problem of low effective channel utilization and poor system fairness caused by traditional channel static spectrum allocation method without considering the mobility characteristics of cognitive users. This method first sets the available channel probability threshold α and the interference edge probability threshold β, predicts each subgraph according to the interference relationship between mobile cognitive users, and predicts each cognitive subgraph in the subgraph according to the interference relationship between mobile cognitive users and authorized users. The user's available channel list, so as to obtain the predicted topology map of the entire network and the predicted available channel list of each cognitive user. Then, from the perspective of fairness, channel allocation is performed for each predicted subgraph one by one. The allocation of each subgraph is to solve the maximum independent set first, and then uniformly allocate channels to the nodes in the subgraph. The present invention is applicable to channel allocation in cognitive radio networks.

This invention discloses a method for scheduling efficient resource of a minisatellite network based on earth observation tasks, and solves the problems that the end-to-end throughput capacity is low and the utilization efficiency of the network resource is low because the network resource is not fully considered during the scheduling process in the earth observation scene of the resource-limited minisatellite network. The method comprises the implementation processes of: according to an initial network topology, determining a node number; at the same time, initializing a network resource scheduling planning time set; according to current network state and resource scheduling conflict restraint, constructing a link scheduling conflict graph by a ground control center; solving a maximal independent set corresponding to the conflict graph to acquire a network conflict-free scheduling link set; by using the link set and a linear programming, solving a resource allocation scheme and a data transmission method capable of mostly optimizing the network efficiency till a time slot is ended. The method improves the resource utilization ratio, increases the returning efficiency of important task data, improves the earth observation network performance of the minisatellite, and is used for scheduling the efficiently transmitted resource of earth observation system data.