147 results about "Time division multiple access" patented technology

This disclosure provides methods, components, devices and systems for coordinated time division multiple access (C-TDMA) in Wi-Fi networks for partial bandwidth transmission opportunity (TXOP) sharing. Some aspects more specifically relate to coordinating TXOP sharing in time and frequency. In some examples, a first access point (AP) obtains a TXOP associated with a bandwidth, allocates a duration of the TXOP to a second AP, and selectively communicates with one or more stations (STAs) associated with the first AP via a first portion of the bandwidth within the duration of the TXOP. In other words, the first AP may selectively communicate with one or more STAs associated with the first AP within the duration of the TXOP that the first AP shared with the second AP. Various disclosed protocols and mechanisms further relate to using resources that would otherwise be unutilized within a framework of coordinated medium access.

The invention relates to the technical field of wireless communication, and discloses a wireless communication control method and system. The method comprises the following steps: generating a periodic configuration structure of a time slot sequence and a node list through communication period calculation and time slot type division on the basis of network topology parameters such as node quantity, distribution position, link quality, transmission delay and the like; heartbeat signal packaging is carried out by using the structure, broadcast power is calculated in combination with a time reference value, and multi-node synchronization is executed by adopting time division multiple access and frequency hopping technologies; triggering downlink data encapsulation and time slot scheduling based on the synchronization mark, generating a transmission record, and driving uplink time slot monitoring and integrity verification; uplink flow characteristics are analyzed, and anti-interference coding and power adaptive adjustment are executed after update configuration is generated, so that closed-loop verification is formed. According to the invention, the multi-node synchronization precision and the anti-interference capability are improved; optimizing the time slot resource utilization rate; and the data transmission integrity and real-time performance are ensured.

This disclosure provides methods, components, devices and systems for schedule announcement enhancements for coordinated time division multiple access (C-TDMA). Some aspects more specifically relate to a sharing AP indicating a schedule announcement for C-TDMA via a frame, such as a poll frame. The frame may include a query to determine interest of one or more shared APs to use a portion of a transmit opportunity (TXOP) obtained by the sharing AP or an indication allocating the portion of the TXOP to the shared APs. The sharing AP may receive a response to the frame via an associated poll response that may indicate an identifier of a shared AP. Various aspects relate more specifically to reallocating one or more fields in a poll frame to indicate information related to the shared TXOP.

The invention discloses a paired time division multiple access method and a paired time division multiple access device in a high dynamic scene. The method comprises the following steps of: mapping each link request into a vertex of a conflict graph; according to a primary conflict and secondary conflict judgment rule, adding undirected edges for vertex pairs with conflicts, and constructing a communication conflict graph; a TDPA time slot allocation problem is formalized into a minimum vertex coloring problem of a communication conflict graph; calculating to obtain a neighborhood cardinal number of each vertex through a global greedy coloring algorithm; carrying out descending sorting on the vertexes according to a neighborhood cardinal number; a minimum positive integer which is not used by a neighborhood vertex is distributed to each vertex in sequence to serve as a time slot, and an initial scheduling baseline is generated; updating the communication conflict graph based on the generated initial scheduling baseline and the current topology change information, and identifying failure vertexes; and re-coloring the failure vertexes through an incremental greedy coloring algorithm to obtain a new scheduling scheme. According to the invention, the problems of low channel utilization rate, poor real-time response, insufficient dynamic adaptability and the like in the prior art are solved.

The invention provides a photovoltaic cleaning robot multi-machine task scheduling and collaborative operation method and system, electronic equipment and a storage medium, and relates to the technical field of multi-machine task scheduling and collaborative operation, and the method comprises the steps: obtaining the position and speed information of each robot in a robot cluster, and constructing a dynamic adjacency graph model; controlling each robot to interact information through an ad hoc network communication relay node by using a time division multiple access protocol, controlling communication delay and broadcasting obstacle information in real time; dividing a to-be-cleaned area based on related information, determining task sub-areas, and realizing adaptive distribution of tasks according to models; and finally, in the cleaning process, by fusing the swarming control of the artificial potential field method, the adjacent robots synchronously clean the boundary and adjust the track, multi-machine efficient collaborative operation of the photovoltaic cleaning robot can be achieved, and the cleaning efficiency and flexibility are improved.

The invention discloses a wireless monitoring system which comprises a multi-parameter wireless sensing terminal, an anti-interference wireless transmission link, an intelligent host receiving system and an emergency backup module. The multi-parameter wireless sensing terminal collects and sends various types of equipment and environment parameters, the anti-interference wireless transmission link guarantees transmission through time division multiple access and the like, the intelligent host receiving system receives and analyzes data, predicts the parameter trend and links an external system, and the emergency backup module caches or takes over the data when a host is abnormal. According to the invention, the limitation of single parameter monitoring is broken through, and multi-dimensional equipment health monitoring is realized; the data transmission stability and integrity are ensured; equipment faults are early warned in advance, and an external system is linked for rapid handling; the endurance of the multi-parameter wireless sensing terminal is prolonged, the long-term operation requirement is met, and the problem of multiple pain points in the prior art is solved.

This disclosure provides methods, components, devices and systems for error condition management in time division multiple access. Some aspects more specifically relate to recovery procedures for error conditions associated with shared transmission opportunities (TXOPs) for a channel. A sharing access point (AP) may perform a recovery procedure to request control of the channel based on the absence of an expected response message from a shared AP. The expected response message may be in response to a message announcing that the sharing AP will share one or more portions of a TXOP controlled by the sharing AP or a message that allocates a portion of the TXOP to a specific shared AP. A shared AP may perform a contention process to access the channel based on the absence of an expected TXOP allocation frame after reception of scheduling announcement from a sharing AP for a TXOP.

This disclosure provides methods, components, devices and systems for schedule announcement enhancements for coordinated time division multiple access (C-TDMA). Some aspects more specifically relate to a sharing AP indicating a schedule announcement for C-TDMA via a frame, such as a poll frame. The frame may include a query to determine interest of one or more shared APs to use a portion of a transmit opportunity (TXOP) obtained by the sharing AP or an indication allocating the portion of the TXOP to the shared APs. The sharing AP may receive a response to the frame via an associated poll response that may indicate an identifier of a shared AP. Various aspects relate more specifically to reallocating one or more fields in a poll frame to indicate information related to the shared TXOP.

The invention belongs to the technical field of wireless communication, and discloses an Internet of Vehicles optimization method and system based on edge computing and time division multiple access, and the method comprises the steps: carrying out the joint optimization of service deployment and replacement, RSU deployment, access control, and task unloading rates in VTUs and RSUs, and achieving the optimization of the Internet of Vehicles. And efficient, low-delay and stable task processing service is provided for vehicle-mounted communication in urban traffic, expressways or disaster areas. According to the method, a double-time-scale optimization strategy is adopted, the decision of service deployment and replacement is carried out on a coarse-grained time scale (frame), and other optimization problems are processed in a fine-grained time scale (time slot). The invention provides an innovative hierarchical DRL algorithm, and in the algorithm, a high-level agent adopts a deep Q network (DQN) proxy and is responsible for optimizing a service deployment and replacement strategy in a frame; and the bottom layer intelligent agent adopts a depth deterministic policy gradient (DDPG) for proxy, and specially solves related optimization problems of task unloading rate, access control and the like in the time slot.

The application discloses a time slot scheduling method of an underwater dynamic multi-hop distribution network based on a time division multiple access protocol, relates to the field of underwater acoustic communication, and is aimed at the underwater multi-hop distribution network, improves the traditional static time slot allocation based on the TDMA protocol, designs a data packet frame structure, comprehensively considers transmission time delays among underwater nodes, dynamically adjusts time slots allocated to the underwater nodes based on the maximum transmission time delay, considers a dynamic node random access condition, and realizes the design of the time slot scheduling method of the underwater dynamic multi-hop distribution network.Compared with the traditional static time slot allocation method, the method can effectively improve the overall throughput of the network and optimize the network operation efficiency.

A method and device for a framework for time division multiple access (TDMA) based multi-access point (MAP) coordination. A method of wireless communication performed by a first access point (AP) comprises transmitting, to a second AP, a message including coordination information for coordinating with the first AP on a basis of MAP. The method includes negotiating, with the second AP, a MAP coordination mechanism to be used for the MAP coordination; and forming a MAP coordination group based on the negotiated MAP coordination mechanism.

The invention discloses a relative navigation method and system suitable for measurement asynchronization and communication delay processing, and relates to the field of navigation. The method solves the problems of measurement asynchronization, communication delay and the like of an existing measurement sharing relative navigation method in practical application. The method comprises the following steps: establishing a total error state equation of a relative navigation system for nodes in a cluster; establishing a multi-source measurement equation of a relative navigation system for the nodes in the cluster; based on a time division multiple access in-turn broadcast type communication mechanism, information data packets are shared by each node in the cluster; constructing a time updating equation and a measurement updating equation, and performing filter time updating and measurement updating; carrying out inertial navigation position extrapolation aiming at measurement asynchronization and communication delay to realize accurate alignment of measurement information containing lagging and an inertial navigation position in time; correcting the error feedback and outputting a relative navigation result. The method is also suitable for the application fields of relative navigation algorithms for measuring asynchronization and communication delay processing and the like.

The application provides a kind of unmanned area overhead transmission line network coverage method, along the line deployment multiple as intelligent spacer intelligent network node, node uses modular hot plug structure, equipped with super capacitor and solid-state battery hybrid energy storage system;Through LoRa communication to build distributed wireless mesh ad hoc network, combined with TDMA time division multiple access and AODV adaptive routing protocol;Utilize the power supply of at least two different principle of multi-source fusion self-powered module power supply;Node collects line monitoring data and carries out edge computing processing, and the processed data is transmitted through multi-hop relay transmission of ad hoc network, and then transmitted to the center master station through the main and standby dual-link redundant transmission architecture.The application can realize long-term stable self-power supply and reliable communication of unmanned transmission line, improve the real-time performance of monitoring data transmission and network invulnerability.

The invention relates to the technical field of wireless communication, and discloses a network-free video transmission scheme implementation method, which comprises the following steps of: firstly, calculating a fitness score according to comprehensive performance parameters such as residual electric quantity and computing resources of nodes through a distributed election algorithm, and electing a unique main control device; then, the main control equipment collects neighbor list information of nodes of the whole network, constructs a weighted global network topological graph, and calculates an optimal relay path with the lowest link cost for a video transmission task based on the topological graph; and finally, the main control equipment generates and broadcasts a global unified time division multiple access time slot allocation table, and accurately allocates conflict-free sending and relay time slots for each node on the optimal path. According to the method, the flexibility of distributed election and the certainty of centralized scheduling are combined, network data collision is effectively avoided, and the reliability and the real-time performance of video transmission in a dynamic and network-free environment are remarkably improved.

The application relates to a time division multiple access time slot allocation method based on a manta ray algorithm and belongs to the technical field of communication networking. The application divides a time frame into an information collection period and a time slot allocation period, and further divides the time slot allocation period into a dedicated time slot period and a dynamic time slot period. In the information collection period, a central node collects time slot application requests of other nodes, judges whether the nodes can continue to apply according to relevant criteria, and gives the nodes priorities according to the traffic volume and the service importance of the nodes. In the dedicated time slot allocation period, high-priority nodes are allocated by using a binary tree block internal equal division method. In the dynamic time slot allocation period, the manta ray algorithm is used to allocate time slots to other nodes. The application is relatively simple to implement, guarantees absolute transmission of the nodes, considers the priorities of the nodes, meets burstiness and long message transmission of the nodes, improves the convergence speed of the algorithm, and improves the overall performance of the network.

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 coherent transmitter (100, 200) for use in a time division multiple access (TDMA) system is operated in multiple states to enable coherent burst transmission. In an OFF state, the transmitter (100, 200) generates a dummy laser output (fd) from either a dummy laser (102) or an active laser (52) tuned to a dummy frequency different from an active frequency (fa), thereby maintaining thermal and bias stability without adding excess power on an upstream channel (22). In an ON state, the active laser (52) produces an active laser output (fa) that is modulated by a quad-parallel Mach-Zehnder (QPMZ) modulator (60) to transmit data. A thermoelectric cooler (TEC) (58) stabilizes laser temperatures, and a variable optical attenuator (VOA) (54) controls output power. The transmitter (100, 200) is suitable for an optical network unit (ONU) (14) in a passive optical network (PON) (10) communicating with an optical line terminal (OLT) (12).

A millimeter-wave automotive radar is disclosed that includes a plurality of millimeter-wave transmitters configured to simultaneously transmit phase-encoded signals according to a phase modulation scheme, and a plurality of subarrays operatively coupled to respective ones of the plurality of millimeter-wave transmitters, each subarray including a predefined number of transmitter elements, and configured to transmit the phase-encoded signals received from a respective one of the millimeter-wave transmitters from other subarrays in different, mutually orthogonal time slots using time division multiplexing.

The application relates to a battery data transmission method and system based on dynamic priority preemption time slots, which comprises the following steps: calculating the dynamic priority of a distributed node according to the data urgency, historical channel quality and basic priority of the distributed node; pre-empting the battery data transmission time slot according to the dynamic priority to perform battery data transmission; and performing a two-stage retransmission strategy to retransmit the battery data when the data transmission fails. The application breaks through the limitation of the fixed time slot allocation of the traditional time division multiple access communication strategy and adapts to the burst communication demand; when the wireless center node based on dynamic priority preemption performs time slot allocation and battery data retransmission, the communication conflict and real-time contradiction in the dense node scene can be effectively solved through software, the reliability, real-time performance and expandability of the system are significantly improved, and the application is suitable for intelligent battery system, electric vehicle, energy storage power station and other high-performance wireless center node application scenes.

The invention relates to an aviation mobile communication method and system based on time division multiple access, belongs to the technical field of satellite communication, and solves the technical problem of low communication quality between a satellite ground station and a mobile communication terminal. Comprising the following steps: in a communication time slot allocated to aviation mobile communication terminals, each aviation mobile communication terminal dispersedly inserts each unique code in a unique code original sequence for auxiliary synchronization into a to-be-sent information code element to construct and obtain a burst signal, and sends the burst signal based on the current sending power; transparently forwarding the burst signal to a satellite ground station by using a satellite transponder; and the satellite ground station extracts the scattered unique codes from the received burst signals, and synchronizes and demodulates the burst signals based on the unique codes to recover the information code elements. And the communication quality between the aviation mobile communication terminal and the satellite ground station is improved.

The invention discloses a Wi-Fi soft scheduling system based on a TSF synchronization token bucket, a communication method, computer equipment and a medium. The system comprises a high-precision TSF synchronization module, a TSF synchronization token bucket gating module and a driving layer scheduling injection and conflict protection module. The high-precision TSF synchronization module is used for providing a uniform time reference with microsecond-level precision and processing system-level errors; the TSF synchronization token bucket gating module is used for realizing time slot scheduling of pseudo TDMA through double constraints of time and capacity, and controlling the authority of a data packet to enter an MAC (Media Access Control) layer; and the driving layer scheduling injection and conflict protection module is used for realizing low-delay transmission injection of the authorization data packet and processing the damage of the competition conflict of the MAC layer to the scheduling certainty through a time slot conflict isolation mechanism. According to the invention, accurate soft control of a data packet transmission time sequence can be realized on a kernel driving layer of an operating system, so that a deterministic time division multiple access effect is simulated on a channel.

The invention discloses a priority and fairness TDMA (Time Division Multiple Access) dynamic time slot allocation method and system, and relates to a time slot allocation and communication technology, and the method comprises the following steps: after sub-network nodes synchronously access a network, each sub-network node sends a message containing time slot related parameters to a cluster head node in a fixed time slot; after the cluster head node receives the information of the sub-nodes, the node comprehensive priority of each sub-network node is calculated; the cluster head node determines a time slot allocation weight of each subnet node according to the node comprehensive priority through a historical time slot occupancy rate and a fairness correction factor; and the cluster head node calculates the number of distributable dynamic time slots of each sub-network node according to the time slot distribution weight, updates the historical time slot occupancy rate, and broadcasts the distribution result to the whole network. According to the method, the fairness correction factor is introduced, the distribution weight is corrected based on the historical time slot occupation condition, the priority guarantee and fairness are flexibly balanced through the adjustable coefficient alpha, and the problems of high priority monopoly and low priority hunger are solved.

A node of a first TDMA network, such as a link 16 network, uses a first receiver to participate in the first network, while using a second receiver to detect and report a second TDMA network, which is not synchronized with the first network, by listening for a characteristic message from the second TDMA network. The timing error between the networks can be estimated from the received message timing. Upon detection, the node can join the second network and / or request updated timing information from the second network. In embodiments where timeslot-specific TRANSEC filters are required, the node selects a TRANSEC filter for a timeslot that is further in the future than an estimated timing error bound. The first and second networks can implement the same network protocol and architecture, differing only due to the timing offset between their network timing references, as would be the case for a split network.

A method for obtaining neural signals from a neural signal sensor includes extracting sensor offset from a neural input signal. Sensor offset is removed from N-channels that share a single amplifier. The neural input signal is acquired from the analog domain by neural electrodes with varying DC-offset and the method includes multiplexing the N-channels via a time divisional multiple access procedure into a single neural amplifier An integrated digitally assisted neural recording system includes an analog multiplexer structured to receive N-channels and to multiplex the N-Channels into a single neural amplifier. A feedback loop is configured to cancel electrode offset voltage in the digital domain by generating electrode offset voltage samples and adding delay to align each electrode offset voltage sample to be subtracted at the neural amplifier in the analog domain.

The invention discloses a random access method and device of a terminal, equipment, a medium and a program product, the terminal receives an inventory instruction sent by read-write equipment, responds to the inventory instruction, and sends an air interface temporary identifier in the same time slot by using a code division multiple access mode or a frequency division multiple access mode to preempt random access resources; and under the condition that the random access resource is successfully preempted, performing time domain serial transmission on uplink data by using a time division multiple access mode. By adopting the invention, the hybrid random access of the terminal can be realized by combining different schedulable resources in the competition access and data transmission stage in the passive Internet of Things communication process, and the access efficiency of the terminal is improved.

The application relates to the technical field of wireless communication, and discloses a multi-standard wireless intercom system fusion communication method, which comprises the following steps: S1. constructing a multi-standard wireless intercom system; S2. constructing a dynamic time slot division model based on time division multiple access (TDMA) technology, and dividing a time axis into a frame structure comprising fixed guarantee time slots and dynamically allocated time slots; S3. calculating the required time slots of each standard by using an adaptive signal mapping algorithm; constructing a synchronization mechanism to realize microsecond-level clock synchronization; S4. a resource allocation is performed by an intelligent scheduling platform according to an enhanced comprehensive communication demand index; and S5. data transmission and processing are realized according to the resource allocation; through time slot division based on the TDMA technology, signal mapping and the synchronization mechanism, the compatibility of the multi-standard wireless intercom system is realized, so that wireless intercom terminals of different standards can communicate in the same system, and the universality and expansibility of the system are improved.

Disclosed herein is a method performed by a sharing access point (AP) to be able to receive a transmission opportunity (TXOP) return frame during coordinated time division multiple access. The method includes providing a temporary channel access parameter set (TCAPS) to a station (STA) associated with the sharing AP, wherein the TCAPS includes a duration parameter indicating a duration for which the STA is to apply the TCAPS, wherein the duration is sufficiently long to encompass a portion of a TXOP that is to be allocated to a shared AP. The method further includes performing a frame exchange with the STA that causes the STA to apply the TCAPS for the duration, transmitting a TXOP sharing frame to the shared AP to allocate the portion of the TXOP to the shared AP, and receiving the TXOP return frame from the shared AP.

A method of operating a coherent transmitter in a time division multiple access (TDMA) system includes operating in an OFF state while the coherent transmitter is not assigned to transmit data in the TDMA system, wherein operating in the OFF state comprises generating a laser output having a dummy frequency different from an active frequency used to transmit data in the TDMA system; and operating in an ON state while the coherent transmitter is assigned to transmit data in the TDMA system, wherein operating in the ON state comprises generating an active laser output having the active frequency and modulating the active laser output using a modulator. Advantageously, the coherent transmitter can be used at an optical network unit (ONU) in a coherent passive optical network (CPON).

Radar systems and methods for generating mixed signal chirps are provided. An example radar system includes a set of transmitters including a plurality of subsets of transmitters; and a processor coupled to the set of transmitters. In operation, the processor applies a beamforming operation on outputs of transmitters within each subset of transmitters, in which a plurality of beamforming operations are respectively applied to the plurality of subsets of transmitters; applies a first multiple input-multiple output (MIMO) scheme to the subsets of transmitters; and applies a second MIMO scheme to the subsets of transmitters that share a common transmitter. The first MIMO scheme may be Doppler division multiple access (DDMA), and the second MIMO scheme may be one of time division multiple access (TDMA) and frequency division multiple access (FDMA).