17 results about "Carrier-sense multiple access" patented technology

The application discloses a modulation and coding adaptive selection method for a mobile ad hoc network based on separation of a control plane and a data plane. In the mobile ad hoc network based on separation of the control plane and the data plane, a carrier sense multiple access (CSMA) mechanism is adopted in a control time slot to compete for sending fused situation information of itself, so as to complete survey and perception of neighbor nodes. The situation information includes link transmission quality and node queue length. In the data plane, the CSMA mechanism is also adopted, but the situation information of the control plane needs to be utilized to form certain 'network order', so as to reduce the decline of throughput caused by error packets and collision. On the basis of a traditional rate adaptive algorithm based on a signal-to-noise ratio (SNR), the algorithm is improved and applied to a mobile ad hoc network device based on separation of the control plane and the data plane.

The invention relates to the technical field of data processing, in particular to an on-satellite remote sensing data task-oriented cross attention fusion compression wireless transmission method, which comprises the following steps that: an intelligent agent takes metadata and channel state information as a state space and takes a parameter adjustment strategy of a cross attention mechanism as an action space; the output decision dynamically adjusts the interaction degree of different modal original data stream features, and the adjusted features are compressed to generate a compressed data stream; a compressed data stream is input into a wireless transmission digital twinborn model constructed on a satellite, a carrier sensing multi-channel access protocol is adopted in an actual transmission stage, and the size of a protocol backoff window is dynamically adjusted by the digital twinborn model according to a rehearsal conflict probability and is optimized by combining a channel capacity change trend prediction result. And finally sending the composite signal of the physical layer network coding. According to the invention, through task-oriented data processing, intelligent compression and digital twinborn rehearsal, the spectrum competition conflict of satellite multi-modal data concurrent transmission is solved.

The application relates to the technical field of underwater acoustic communication, and discloses a method and system for dynamically allocating resources of an underwater voice communication system. The method comprises the following steps: setting a multi-user priority strategy according to a formation modular grouping; adopting a hybrid access mechanism of fusion of time division multiple access and carrier sense multiple access / collision avoidance, dividing communication channels into inter-group time slots and intra-group time slots, and competing for access to idle sub-carrier clusters in the time slots through a CSMA / CA mechanism; predicting a future state of an underwater acoustic channel; based on the predicted future state, adaptively switching a modulation and coding scheme according to a preset signal-to-noise ratio threshold; distributing sub-carrier bands to users with the largest channel gain based on a channel gain matrix; and combining the multi-user priority strategy, the hybrid access mechanism and the modulation and coding scheme to jointly optimize and distribute sub-carriers, bit loading and transmission power. Through dynamic resource allocation and adaptive transmission optimization, the application effectively improves the resource utilization rate and transmission quality of underwater voice communication.

A closed loop carrier sense multiple access multiuser request to send and clear to send handshaking system is provided to efficiently allocate licensed and unlicensed spectrum for a plurality of mobile devices and across different base stations and mobile network operators. A user equipment device can be connected to a base station device via a first frequency in licensed spectrum, and a second frequency in unlicensed spectrum. The air interface on the first frequency can then be used to coordinate physical and virtual carrier sensing on a second frequency among a plurality of user equipment devices. Moreover, carrier sensing results from a plurality of UEs can be reported a base station device via the first frequency in licensed spectrum. The base station device can then schedule multiple user multiple input, multiple output (MU-MIMO) transmissions to a plurality of UEs on the second frequency in unlicensed spectrum.

A wireless local area network (WLAN) uses enhanced distributed channel access (EDCA) in an EDCA queue system to support real-time application (RTA) packets, which are delay sensitive, and non-RTA packets on a network supporting carrier sense multiple access / collision avoidance (CSMA / CA). At least one new access category (AC) and associated transmit queue is created to queue RTA packets, while non-RTA packets are queued to the original transmit queues in the EDCA queue system. A new EDCA function (EDCAF) is created for the new access category (AC) transmit queue for RTA packets, where the RTA queue is able to contend for the channel before the expected RTA packet arrives.

A computer-implemented method for an IEEE 802.15.4 device is provided based on a suspendable carrier sense multiple access with collision avoidance (CSMA / CA) control program and a standard CSMA / CA control program for an IEEE 802.15.4 network consisting of IEEE 802.15.4 devices. The computer-implemented method is provided on the IEEE 802.15.4 device and causes a processor of the IEEE 802.15.4 device to perform steps including determining permission for back-off suspend and an intention of the IEEE 802.15.4 device to execute a back-off suspend, and selecting a suspendable CSMA / CA control program if back-off suspend is permitted and the IEEE 802.15.4 device intends to execute a back-off suspend. The suspendable CSMA / CA control program is configured to perform active CCA within each unit backoff period, suspend backoff if the channel is detected to be busy, perform CCA if the backoff is completed, transmit a frame if the detected channel condition is clear, increment a number of backoffs (NB) if the detected channel condition is busy, determine whether NB exceeds a threshold macMaxCSMABackoffs, increment a number of retransmissions (NR) if NB exceeds the threshold macMaxCSMABackoffs, and discard the frame if NR exceeds a threshold macMaxFrameRetries.

A computer-implemented method for an IEEE 802.15.4 device is provided based on a suspendable carrier sense multiple access with collision avoidance (CSMA / CA) control program and a standard CSMA / CA control program for an IEEE 802.15.4 network consisting of IEEE 802.15.4 devices. The computer-implemented method is provided on the IEEE 802.15.4 device and causes a processor of the IEEE 802.15.4 device to perform steps including determining permission for back-off suspend and an intention of the IEEE 802.15.4 device to execute a back-off suspend, and selecting a suspendable CSMA / CA control program if back-off suspend is permitted and the IEEE 802.15.4 device intends to execute a back-off suspend. The suspendable CSMA / CA control program is configured to perform active CCA within each unit backoff period, suspend backoff if the channel is detected to be busy, perform CCA if the backoff is completed, transmit a frame if the detected channel condition is clear, increment a number of backoffs (NB) if the detected channel condition is busy, determine whether NB exceeds a threshold macMaxCSMABackoffs, increment a number of retransmissions (NR) if NB exceeds the threshold macMaxCSMABackoffs, and discard the frame if NR exceeds a threshold macMaxFrameRetries.

This invention relates to the field of data processing technology and discloses a big data analysis system based on the usage habits of power bank users. It includes a cloud-based big data analysis platform, a cabinet control node, and a power bank communication module. The cloud-based big data analysis platform extracts historical rental characteristics to construct a data increment prediction model, generates predicted data volume labels, and sends them to the cabinet control node. The cabinet control node calculates the available channel evaluation index based on the total predicted data volume and issues power attenuation factor and extended contention window commands when the volume is below a preset congestion threshold. The power bank communication module reduces the gain of the RF front-end amplifier according to the commands and resets the upper limit of the random backoff counter in the carrier sense multiple access (CMI) collision avoidance mechanism to complete data upload. This solution reduces the probability of co-channel interference and the number of data retransmissions, shortens the channel occupancy time, and avoids communication link disconnection due to channel congestion.

The application provides a wireless data center system, a communication method, an electronic device and a chip, and is applied to the technical field of data center wireless network, and comprises a mapping node and a reduction node, a wireless sending module is arranged on the mapping node, and a wireless correlation module is arranged on the reduction node; the wireless sending module sends data through a sending antenna, the wireless correlation module receives data through a receiving antenna, and the sending antenna and the receiving antenna work in the same channel. The application arranges the wireless sending module in the mapping node and the wireless correlation module on the reduction node. Compared with the access mechanism of the traditional wireless transmission which adopts the carrier sense multiple access with collision avoidance, only one node can transmit at each time, in the application, the sending antenna and the receiving antenna work in the same channel, multiple mapping nodes can simultaneously transmit, and the data transmission efficiency between the wireless data center nodes is improved.

The application discloses a UAV deployment method based on carrier sensing multiple access and collision avoidance protocol, and relates to wireless communication. In the prior art, it is difficult to systematically evaluate the influence of flight height on dynamic access performance. In the UAV uplink communication system supporting ground user mobility, the application quantifies the trade-off relationship between system coverage efficiency and access performance by CDR, and selects the height with the maximum CDR as the optimal deployment height of the UAV. The advantage is that the CSMA / CA parameters are adjusted to match the new link delay characteristics. When coverage and delay are incompatible, the algorithm prioritizes delay and gives executable configurations of backup height and minimum feasible coverage. The onboard computing unit can run in real time, and can stably output deployable optimal / suboptimal configurations under different signal-to-noise ratio requirements and urban propagation environments, realize the joint optimization of communication reliability and service timeliness, and be suitable for scenarios such as delay-sensitive space-ground integration communication.

The invention discloses a resource optimization and access protocol design method for dual-medium communication, which comprises the following steps: a relay node broadcasts a beacon frame carrying synchronization information, and a source node sends a management frame carrying priority information to the relay node; the source node selects a power line communication channel or a wireless communication channel through a channel evaluation algorithm according to the service type; the source node accesses the relay node based on a first frame structure, the first frame structure comprises a random access stage, and an access mode of the source node is confirmed based on priority information; the relay node dynamically determines a relay scheme based on a signal-to-noise ratio and double thresholds, and feeds back a decision through a first field in an ACK frame structure; a relay node sends data to a destination node through a superframe formed by mixing a carrier sense multiple access / collision avoidance (CSMA / CA) protocol and a time division multiple access protocol, wherein the superframe comprises a non-competitive stage and a competitive stage. Thus, the data is processed based on the priority, the flexibility of the relay scheme is enhanced, and the reliability and efficiency of data transmission are improved.

The embodiment of the invention relates to carrier sense multiple access (CSMA) equipment with power adaptation, a method, a device and a computer readable storage medium. The method includes measuring, at a terminal device, at least one received power associated with an energy detection (ED) time interval of an ED process; determining a transmission power associated with a transmission duration of the terminal device based on at least one of the at least one received power or the ED time interval; and performing a transmission over a transmission duration based on the transmission power.

The invention relates to the technical field of wireless communication, in particular to a method for optimizing a WIFI7 wireless router CSMA-CA back-off algorithm based on RSSI (Received Signal Strength Indicator). The method comprises the following steps: a wireless terminal continuously monitors the state of a wireless channel through a carrier monitoring multi-channel access mechanism, immediately sends a data frame when judging that the channel is in an idle state, and triggers initialization of a backoff process when detecting that the channel is in a busy state; and acquiring a received signal strength indication (RSSI) value of the wireless terminal in real time, and performing discretization processing based on an absolute value of the RSSI value. According to the invention, a self-adaptive channel competition mechanism based on a physical layer state is constructed by introducing received signal strength indication (RSSI) into a backoff window value calculation kernel. Specifically, a discretization function Round (RSSI / 10) is adopted to quantize a signal quality level, and a random disturbance factor bound with an MAC address is superposed, so that a high-quality terminal dynamically obtains a smaller backoff window value.

Provided is a computer-implemented method for an IEEE 802.15. 4 device, the computer-implemented method being used for an IEEE 802.15. 4 network composed of the IEEE 802.15. 4 device based on a suspensible carrier sense multiple access / collision avoidance (CSMA / CA) control program and a standard CSMA / CA control program. The computer-implemented method is provided on an IEEE 802.15. 4 device, and causes a processor of the IEEE 802.15. 4 device to perform the steps including determining permission of a backoff suspend and an intention of the IEEE 802.15. 4 device to perform the backoff suspend, and selecting a suspend CSMA / CA control program if the backoff suspend is permitted and the IEEE 802.15. 4 device intends to perform the backoff suspend. The suspend CSMA / CA control program is configured to perform active CCA in each unit backoff period, and suspend backoff if a channel is detected to be busy, perform CCA when backoff is completed, transmit a frame when a detected channel state is an idle state, or increments a number of backoff (NB) when the detected channel state is a busy state, determine whether the NB exceeds macMaxCSMABackoff, and transmit a frame when the detected channel state is an idle state. The number of retransmissions (NR) is incremented when the NB exceeds the macMaxCSMABacks, and the frame is discarded when the NR exceeds the macMaxFrameRetries.

Wireless devices may perform modified carrier sense multiple access (CSMA) techniques in order to increase reliability while maintaining a reasonable latency for communications. The wireless devices may perform listen-before-talk (LBT) techniques using an adaptive transmission threshold (e.g., an adaptive CSMA threshold). The transmission threshold may be compared to a measured signal strength magnitude to determine whether the frequency channel is quiet enough for transmission of a packet. The transmission threshold may be initially set to equal a minimum value. The wireless device may increase the transmission threshold after each instance of LBT failure to allow the wireless device to get progressively more likely to transmit the packet each time LBT fails.

A computer-implemented method for providing an IEEE 802.15. 4 device for an IEEE 802.15. 4 network consisting of the IEEE 802.15. 4 device based on a carrier sense multiple access (CSMA / CA) control program with collision avoidance that can be suspended and a standard CSMA / CA control program. The computer-implemented method is provided on an IEEE 802.15. 4 device and causes a processor of the IEEE 802.15. 4 device to perform steps including determining a permission of a backoff suspend and an intention of the IEEE 802.15. 4 device to perform the backoff suspend, and selecting a CSMA / CA control program that can be suspended if the backoff suspend is permitted and the IEEE 802.15. 4 device intends to perform the backoff suspend. The suspend CSMA / CA control program is configured to perform active CCA in each unit backoff period, and suspend backoff if a channel is detected to be busy, perform CCA when backoff is completed, transmit a frame when the detected channel state is an idle state, or increments a backoff number (NB) when the detected channel state is a busy state, determine whether the NB exceeds macMaxCSMABackoff, and transmit the frame when the detected channel state is an idle state. The number of retransmissions (NR) is incremented when the NB exceeds the macMaxCSMABacks, and the frame is discarded when the NR exceeds the macMaxFrameRetries.

The invention belongs to the technical field of wireless communication networks, and particularly relates to a monitoring data transmission method and system based on a wireless network, and the method comprises the steps: collecting the internal force data of a steel support and the electromagnetic interference data of a channel environment; determining the initial sending probability of each wireless sensor node; constructing a historical time window sliding queue of the wireless sensor nodes, and determining an interference time sequence smoothing factor and a final sending probability; and performing access control and data transmission scheduling on the wireless sensor nodes by using the optimized p-persistent carrier monitoring multi-channel access algorithm. According to the invention, by analyzing the numerical value change characteristics of the steel support internal force data and the electromagnetic interference data, the transmission probability of the wireless sensor node is adaptively optimized, continuous strong mechanical electromagnetic interference is effectively avoided, the network anti-interference capability is enhanced, and the low-delay, safe and stable transmission of the engineering high-risk early warning monitoring data is ensured.