40results about How to "Improve time slot utilization" patented technology

The invention discloses a self-adaption adjustment method of contention windows in an 802.11e wireless network. A network load state is determined according to a network conflict rate via a wireless access point, and the contention windows are adjusted in a self-adaption mode according to the network load state. If the conflict rate is detected to be greater than a given threshold value, the access probability between an AP of current network load and an site is calculated in a multiplicative decrease mode according to an actual conflict rate value; if the conflict rate is detected to be smaller than or equal to the given threshold value, the access probability adapted for the current network load is calculated in a linear increase mode according to the actual conflict rate value. On this basis, an AP access probability is optimized according to the length of an AP current queue. Finally, the largest contention windows and the smallest contention windows between the AP and the site are respectively calculated according to the relations between the access probability and the contention windows. According to the method, the values of the contention windows can be adjusted in a self-adaption mode on the basis of network load conditions, so that the effective availability of a wireless channel is improved, network throughput is increased, and network delay is reduced.

The invention discloses an MAC access method based on a terahertz ultra-high-speed wireless network. The method includes the following steps that a Beacon1 frame is broadcasted by a PNC at the Beacon1 period; timeslot applications of DEVs are received by the PNC at the CAP period or SAP period; timeslots are distributed and distribution results are broadcasted by the PNC at the Beacon2 period; after a Beacon2 broadcast frame is received, data transmission is carried out in the timeslot, of each DEV of the CTA timeslot, in the CTAP time frame in the TDMA mode; afterwards, operation in the superframe is finished, and operation in the next superframe is carried out. The MAC access method based on the terahertz ultra-high-speed wireless network solves the problems of redundant control expenses and data transmission time delay of existing relevant MAC access methods and timeslot resource waste.

The invention discloses a method and device for realizing dynamic time slot allocation. The method includes: a server sorts the nodes that need to allocate time slots according to the dynamic priority table, and when each node has a burst of emergency traffic, according to the priority The level dynamically allocates time slots for each node; the server selects the appropriate sending time slot for each node according to the message length of the burst emergency traffic. The dynamic allocation time slot of the present invention is based on the dynamic priority table, and the server allocates the time slot to each network node according to the priority; at the same time, the appropriate time slot can be selected according to the length information of the message sent by each node and the time slot used by the node last time. The transmission time slot greatly improves the utilization rate of the time slot, and ensures the timely and effective communication of the data link emergency node information; it also meets the transmission needs of the node emergency message information, and solves the existing problems in the network in the prior art. When sending business flows, it cannot adapt to the problem of a network with a dynamically changing scale.

The invention provides a method for realizing a wireless ad hoc network. The wireless ad hoc network is used for dividing in-cluster and inter-cluster control information to different areas in a wireless frame structure. Furthermore a control area and a data area which are specialized for each broadcast service are divided in the wireless frame structure. The method realizes overall scheduling on different types of services with different priorities through a specific frame structure. Furthermore through reserving a specialized control resource area and a data resource area for the high-priority broadcast service, service priority insurance is realized.

The invention discloses a semi-structured transmission dispatching method orienting wireless sensor network data collection. The method is characterized by comprising the steps that 1, breadth-first search is carried out on a network communication graph, so that a slack semi-structured data collection route topological graph is constructed; 2, a link interference graph is constructed according to the main interference and subsidiary interference relation between transmission links in a network; 3, link weight interference factors are defined, so that the interference intensity caused to other links of the network from transmission loads of sending nodes and sending links is comprehensively weighed; 4, the dynamic link selection and time slot allocation strategy based on preference of the minimum weight is carried out; 5, a node dormant state is controlled in an explicit mode, and a data collection period is adjusted in a self-adaptive mode. According to the method, routing and dispatching are designed in a unified mode on the basis of a cross-layer design idea, the time slot utilization rate of dispatching is increased by fully utilizing the redundancy of a path, time delay of data collection is shortened, and the handling capacity of the network is improved. The method is applied to the wireless sensor network with the high requirement for the real-time property.

The invention provides a reliable Terahertz wireless personal area network access method with high time slot utilization. The method comprises the following step: dividing the network running time into multiple superframes with different lengths, wherein each superframe consists of three ordered time periods that are Beacon, CAP and CTAP. The method includes the following three new mechanisms:'multi-dimensional bidirectional subframe body extraction', 'PNC adaptively using CTA time slots based on monitoring" and 'dynamization of the number of subframe head fields', and all the new mechanisms work in the CTAP time period of the superframes. Through the steps of maximally extracting subframe bodies in standard aggregation frames from three dimensions and two directions, enabling the PNCto adaptively use the CTA time slot that is allocated to DEV but is not used when the PNC has data to be transmitted but does not have allocated time slots, and dynamically adjusting the number of the subframe head fields in the standard aggregation frames according to the actual number of the subframe heads, the new access method achieves the effects of improving the reliability and time slot utilization of data frame transmission as well as reducing control fields, and thus the success rate and throughput of the data frame transmission can be improved, and the control overhead and the average delay of data frames can be reduced.

The invention discloses a time slot distribution method based on a multi-factor priority in a body area network. The method comprises two parts of a multi-factor design and time slot distribution. The method comprises the following steps of firstly, through calculating a multi-factor weight, acquiring an initial time slot distribution sequence; secondly, considering node heterogeneity, through a time delay restriction, setting a priority and calculating maximum time delay of data after time slot distribution so as to distribute a high priority node time slot occupation number again; then, under the condition that a time slot has a residual amount, according to a descending order, distributing a low priority node time slot occupation number, and changing the priority into a high grade; and finally, in an original sequence, removing the low priority node time slot occupation number so as to acquire an optimal time slot distribution scheme. In the invention, a node can fully use the time slot; and under the condition that a packet loss ratio and an overflow rate are guaranteed, sensor node power consumption is minimum and a service life of the node is prolonged.

The invention discloses a hybrid MAC protocol optimization design method based on wireless optical communication, and the method comprises the steps: S1, enabling a Sink node to carry out the instruction wake-up of other nodes, enabling the other nodes to wake up at a random time, and starting to carry out the competition of a cluster head, and carrying out the preemption of a time slot; S2, entering a downlink transmission stage, performing relative positioning between nodes and cluster head updating tasks, and finishing downlink instruction transmission and cluster head updating tasks in each odd number of turns; and S3, entering an uplink stage, and performing time slot optimization in the delay tolerant network based on a time slot transfer mechanism of link quality evaluation. According to the time slot transfer mechanism based on link quality evaluation, time slot optimization in the delay tolerant network is carried out, and the time slot utilization rate of networking is improved.

The invention discloses a signal emitting and receiving method based on signal compression and extrapolation technology and an implementation device of the signal emitting and receiving method based on the signal compression and extrapolation technology, and relates to the field of communication. The signal emitting and receiving method based on the signal compression and extrapolation technology solves the problems that a system is low in slot time use rate and incapable of transmitting more signals in limited time. The method comprises the steps of forming an input sequence in a pulse mode, compressing the input sequence in a wave form mode, conversing the input sequence in a parallel-to-serial mode, filtering the input sequence, sending the input sequence through an antenna, receiving a wave form signal through an antenna by a receiving end, filtering the signal, converting the signal in a parallel-to-serial mode, sampling the signal, processing the signal in an extrapolation mode, and obtaining an input symbol sequence of a sending end. The implementation device comprises a sending unit and a receiving unit. The sending unit enables the signal to be compressed by a sending end parallel-to-serial converter, a pulse forming circuit and a time window circuit and sends the signal to an information channel through an original communication method. The receiving unit enables the received signal to pass a sampling circuit and an extrapolation circuit, obtains an extrapolated signal sequence, and obtains the input symbol sequence of the sending end through a receiving end judging device. The signal emitting and receiving method based on the signal compression and extrapolation technology is applicable to the field of communication.