39results about How to "Improve space reuse" patented technology

The invention discloses an implement method of power control cognition MAC protocol based on time division multiple access (TDMA). The method comprises the following steps: adopting strict time slot division, finishing time slot allocation among node pairs by a three-way handshake manner, namely, reserving application, reserving confirmation and deciding sending; realizing collision-free transmission in node communication process; and introducing a power control mechanism to improve the reuse rate of cyber space. The method can eliminate problems of multiple channels hiding a send terminal, multiple channels hiding a receiving terminal and multiple channels exposing terminals, and can dramatically decrease the impact on network performance brought by the problem of multiple channels hidingthe send terminal. The simulation result indicates, compared with dynamic spectrum access MAC (DSA-MAC) protocol, the invention can effectively enhance network throughput and decrease access time delay with the increment of network business volume.

The invention relates to a transmission control frame method based on dynamic power adjustment which is in the field of wireless local area network transmission technology, wireless self-organized network communication nodes detects around other nodes, and obtains transmission distance communicated with around nodes, a transmitting power table is established communicated with around nodes; then, communications nodes receives around other nodes control frame, and obtains the optimal transmitting power communicated with other nodes through the optimal power formula, transmitting power in the node transmitting power table is updated by the optimal transmitting power; again, when communication nodes sending frame to around nodes, the first judges frame, if the frame is the RTS / CTS control frame, thus the node finds the optimal transmitting power from self-transmitting power table, and sends control the frame; if the frame is data frame, thus sending in accordance with the largest transmission power. The invention improves integral network communication space reuse degree, and increases network integral throughput greatly.

A method in a network node (115) is disclosed. The method comprises allocating (1204) a pool of radio resources for vehicle-to-other (V2x) communication by a plurality of wireless devices (110), and dividing (1208) the allocated pool of radio resources for V2x communication into a plurality of orthogonal sets of radio resources, each set of radio resources having an associated set identifier comprising one of a plurality of positive integers. The method further comprises assigning (1212) one or more radio resource sets to each wireless device among the plurality of wireless devices based at least in part on a radio- compatibility characteristic, and communicating (1216) to each wireless device the assigned set of radio resources to use.

There is provided beam forming using an antenna array. The antenna array is configured to transmit across an angular sector. The angular sector is divided into at least two sub-sectors by respective port weights being applied to respective physical antenna ports of the antenna array. A respective set of virtual antenna ports is determined for each sub-sector. A first set of reference signals for acquiring channel state information on the set of virtual antenna ports is alternatingly transmitted in each one of the at least two sub-sectors.

A method of selecting antenna segments for transmission and / or reception in a MIMO wireless transmission system using sectorized directional antennas, includes the steps of selecting, from an initial set of ranked link antenna patterns, a link antenna pattern having the best average rank, at predetermined time intervals, successively selecting a subset of link antenna patterns having average ranks within a predetermined distance to the best average rank, determining an average link performance of the link antenna patterns selected in the preceding step, determining an average rank of the link antenna patterns, for which the average link performance has been determined in the preceding step, selecting the link antenna pattern having the best average rank, and repeating the process at the next predetermined time interval.

A method performed by a first communication apparatus for transmitting data to a second communication apparatus in a communication channel shared with a communication link including a third communication apparatus, wherein all of the first communication apparatus, the second communication apparatus and the third communication apparatus employing directional transmission, the method comprising: determining there is data to be transmitted to the second communication apparatus; and transmitting the data to the second communication apparatus before listening to the channel.

A method and system for improving spatial reuse in a wireless local area network (WLAN) by per-client dynamic power management. Each access point of the WLAN associates each of its clients with a minimum power level. A central controller of the WLAN generates a schedule for transmission at different power levels, and each access point varies its transmission power level based on the schedule. An access point transmits data packets, at the scheduled transmission power level, to clients associated with a minimum power level that is less than the scheduled power level.

There is provided beam forming using an antenna array configured to transmit across an angular sector. A first set of virtual antenna ports is determined by a mapping of physical antenna ports of the antenna array, the first set of virtual antenna ports defining a beam pattern. A first set of reference signals for acquiring channel state information is transmitted over the first set of virtual antenna ports. Angular information about a wireless transceiver device receiving the transmitted first set of reference signals is acquired. The beam pattern is adapted based on an accuracy of the angular information and / or the angular information itself.

The invention provides an underwater acoustic network reservation multi-access method based on active time reversal, and relates to the technical field of underwater acoustic communication and underwater networks. Multiple access in the data transmission process among nodes, which is applicable to a distributed acoustic network MAC layer, is adopted, so that the transmission conflicts are avoided, the success probability and channel utilization rate of once transmission are substantially improved, and the networking energy consumption is lowered; by means of active TR space-time focusing and the space change characteristic of an underwater acoustic channel, the disadvantages are converted into advantages, the broadcasting characteristics of the underwater acoustic channel is weakened, the signal interference among adjacent links under a distributed multi-hop environment is effectively isolated, and the good transmission concealment and security of the multi-access method are realized by channel broadcasting weakening, so that the space multiplexing is improved, the network throughput is increased, the time delay of the system is shortened, and energy is saved.

Provided are a method of performing contention based channel access by classifying a contention period into a beamformable contention period in which a beamforming is allowed and a non-beamformable contention period in which the beamforming is interrupted so as to resolve an issue regarding channel access occurring due to an introduction of a directional antenna for handling a path loss in a wideband wireless communication system according to an embodiment of the present invention, and a method for maximizing a spatial reuse gain by managing, for each direction, information about a transmission time of a message received from a dispersion device.

The invention relates to a routing method suitable for the static ad hoc formation. Aiming at the special organization structure of the static Ad hoc formation, a centralized topologic control is carried out inside the ad hoc formation; the formations are clustered according to the results of the topologic control; and a new double-frequency multi-stage routing method is adopted so as to ensure the reliable and quick routing establishment and the data transmission inside the formation and among the members inside the formation. The method is characterized in that the method includes the following steps: the topologic control in the formation, the establishment of the formation network structure, the maintenance of the formation network structure, the search of a transmission router, the maintenance of the transmission router, the routing error control and the re-establishment of the router. By adopting the method, the reliable and quick routing establishment and the data transmission in the formation and among the members inside the formation can be realized, the interference in the wireless transmission can be reduced, the network capacity can be further improved, the node service life is prolonged, and the network survival time is increased.

Beamforming using an antenna array configured to transmit across angular sectors is provided. A first set of virtual antenna ports is determined by mapping of physical antenna ports of the antenna array, the first set of virtual antenna ports defining a beam pattern. A first set of reference signals for acquiring channel state information is transmitted through a first set of virtual antenna ports. Angular information related to wireless transceiver devices receiving the transmitted first set of reference signals is obtained. The beam pattern is adapted based on the accuracy of the angular information and / or the angular information itself.

A method performed by a first communication apparatus for transmitting data to a second communication apparatus in a communication channel shared with a communication link including a third communication apparatus, wherein all of the first communication apparatus, the second communication apparatus and the third communication apparatus employing directional transmission, the method comprising: determining there is data to be transmitted to the second communication apparatus; and transmitting the data to the second communication apparatus before listening to the channel.

The invention provides a method for implementing an aeronautical Ad hoc network STDMA (Self Organizing Time Division Multiple Access) protocol based on a directional antenna. Through adoption of a directional antenna model, node directional transmission and directional reception, the spatial reuse is enhanced. Meanwhile, a method of combining fixed time slot assignment with dynamic time slot assignment is adopted, namely, the fixed time slot assignment is realized on the basis of a polling strategy, and optimization of dynamic time slot scheduling is realized in combination with an ADS-B system. In the case of emergency demands, reservation of additional time slots is performed, so that time delay of services can be ensured at a certain degree, and an emergency data transmission demand can be met. Through adoption of the method, time slot resources are fully utilized, and the spatial reuse and network throughput are enhanced.

The invention provides a symmetric carrier elimination optical communication method, a visible light transceiver and a visible light communication terminal, which are used for reducing the alignment difficulty of point-to-point interconnection. According to the symmetric carrier elimination optical communication method, a visible light communication terminal and an opposite terminal are communicated with the same reflecting surface. The method comprises: a visible light communication terminal sending a first visible light signal to a reflecting surface; the visible light communication terminalreceiving the visible light signal and converting into a first target electric signal; wherein the first target electric signal comprises a first receiving signal and a second receiving signal; wherein the first receiving signal is an electric signal which is transmitted to the reflecting surface by the first visible light signal and then received by the visible light communication terminal; wherein the second receiving signal is an electric signal received by the visible light communication terminal after the second visible light signal is transmitted to the reflecting surface; the visible light communication terminal performing channel estimation on the first received signal to obtain an estimated signal; and subtracting the estimation signal from the first target electric signal to obtain an estimation signal of the second receiving signal.

The invention provides a signal monitoring method, system and device and a storage medium, and the method comprises the steps: setting a register in a processor for storing an abnormal signal, and setting a data reading address pointer and a data writing address pointer; setting a timer in a processor, reading a count value of the timer in response to the detected abnormal signal, and storing the count value in the register; storing the state of the abnormal signal to a data write-in address, and moving a data write-in address pointer towards a first direction; and in response to the fact that the communication interval time between the processor and the BMC exceeds a threshold value, using the time for triggering interruption as the time for occurrence of the abnormal data received next time. According to the invention, a CPLD and BMC bidirectional timing mechanism is adopted to record the triggering time of the abnormal signal, so that subsequent maintenance personnel can conveniently locate the cause of the abnormality according to the occurrence time of the abnormality.

A method in a network node (115) is disclosed. The method includes allocating (1204) a pool of radio resources for vehicle-to-other (V2x) communications of a plurality of wireless devices (110), and dividing (1208) the pool of radio resources allocated for V2x communications into a plurality of orthogonal sets of radio resources , each radio resource set has an associated set identifier comprising one of a plurality of positive integers. The method also includes assigning (1212) one or more sets of radio resources to each of the plurality of wireless devices based at least in part on the radio compatibility characteristic, and communicating (1216) the assigned set of radio resources to each wireless device for use.

There is provided beam forming using an antenna array. The antenna array is configured to transmit across an angular sector. The angular sector is divided into at least two sub-sectors by respective port weights being applied to respective physical antenna ports of the antenna array. A respective set of virtual antenna ports is determined for each sub-sector. A first set of reference signals for acquiring channel state information on the set of virtual antenna ports is alternatingly transmitted in each one of the at least two sub-sectors.

The invention provides a carrier sensing method based on a dynamic idle channel assessment threshold. According to the method, the existing carrier sensing mechanism is improved, and a CCA (Clear Channel Assessment) threshold is adjusted and an effective range of an NAV (Network Allocation Vector) is controlled according to the channel condition, so that the concurrent transmission in a network is increased and the network throughput is improved. According to the method, the CCA threshold is dynamically computed and adjusted according to the receiving power, so that the spatial reuse of the network can be effectively improved, meanwhile, through carrying an interference margin and a probability of acceptance at a CTS (Clear To Send) group, the range of action of the NAV in the CTS group is effectively controlled, and the spatial reuse is further improved, so that the network throughput is improved.