Abstract:
A method for transmitting packets and a network system thereof are provided. In the present invention, each packet entering the network system is added an assigning tag to indicate the arrival time of the packet, and at least two queues in a node of the network system are used for respectively sorting the local packets of the node and the relayed packets of the preceding node. The order of the packet for transmitting can be decided by comparing the assigning tags of the two packets positioned at first order in different queues. Therefore, a condition of First-In First-Out (FIFO) is satisfied in the network system, and the sequence for transmitting packets is arbitrated fair.
Abstract:
A method and system are disclosed for constructing a power spectrum based connection admission control table and using such a table in a communications network, such as an ATM network. Power spectrum parameters, such as the power spectrum DC component .gamma., half power bandwidth B.sub.w and average power .PSI..sub.w are transformed to .gamma., an equivalent half power bandwidth B.sub.e and an equivalent average power .PSI..sub.e, where B.sub.e is a predetermined constant. Since B.sub.e is constant, the transformation reduces the memory requirements for constructing a connection admission control table.
Abstract:
The present invention is related to a method adapted to be used in hashing algorithm for reducing conflict probability which comprises the steps of receiving a first physical address of a frame; generating a hashing address corresponding to the first physical address; comparing a second physical address corresponding to the hashing address with the first physical address to determine if the first and the second physical addresses match with each other; completing a packet calling process when the first and the second physical addresses match with each other, but going back to the comparing process when the first and the second physical addresses do not match with each other, to determine whether there is another second physical address corresponding to the hashing address and matching with the first physical address; and ending the packet calling process when a number of times that the comparing process is proceeded is greater than a reference value. By this method, a specific conflict probability is obtained, and according to the results, the conflict probability and the broadcasting probability are reduced and the source of the network is saved.
Abstract:
A system for channel selection management in a wireless communication network. The system includes a memory module configured to store at least one channel condition related to at least one infrastructure station among a plurality of infrastructure stations in the wireless communication network, wherein each of the plurality of infrastructure stations is able to monitor a channel condition of a channel between the each infrastructure station and a mobile station; a compare module configured to compare a channel condition related to one of the plurality of infrastructure stations with a threshold and provide a signal for a comparison result; a control module configured to provide a control information based on the signal from the compare module; and a selection module configured to select one of the at least one infrastructure station and notify the selected infrastructure station to serve the mobile station based on the control information from the control module.
Abstract:
A method for a transmission system selecting one of a plurality of transmission architectures to transmit a multicast-and-broadcast service is provided. The transmission system comprises at least one base station participating the transmission of the multicast-and-broadcast service. The method comprises recording a number of subscribers for subscribing the multicast-and-broadcast service within the coverage range of each of the base stations. According to the subscriber number and the number of the base stations, each of the transmission architectures is mapped to average cell efficiency. The average cell efficiency of each of the transmission architectures is analyzed. The transmission architecture corresponding to the maximum average cell efficiency is selected for the transmission system transmitting the multicast-and-broadcast service.
Abstract:
Methods for multi-user detection in a CDMA-based channel for use in a base station receiver are provided. Signals, each including a CDMA code, are received. Correlation operations are performed on CDMA codes of received signals respectively to obtain corresponding first correlation values. CDMA codes are divided into first and second code groups according to a threshold and corresponding first correlation values. An interference cancellation procedure is performed on received signals to remove signals corresponding to first code group therefrom and to obtain a removed signal. Correlation operations are performed on CDMA codes of removed signal to obtain corresponding second correlation values. Each first correlation value is subtracted from a corresponding second correlation value and compared with a threshold to generate a comparison result. Whether CDMA codes within first code group are correct are determined according to comparison results, wherein the threshold is dynamically adjusted according to comparison results.
Abstract:
A method for managing a call admission controller in a multi-hop wireless backhaul network is illustrated. The method provides a call access control mechanism in a multi-hop wireless backhaul network system by calculating at least one service quality parameter in the network and determining if service data transmitted from relay nodes is allowed to enter a gateway of the network according to the at least one service quality parameter. In exemplary embodiments of present invention, the service quality parameter includes a throughput, an average delay of packets, a number of remote devices, a packet loss rate, a number of the relay nodes, and an amount of service data of a specific class traffic in the network. A topology of the network may be a ring, a chain, or a tree topology, and a ripple protocol is utilized as media access control protocol in the network.
Abstract:
A system for data communication in a wireless mesh network that comprises a wired gateway, and a plurality of nodes stationary with respect to each other being disposed in a pattern including at least one path, each of the plurality of nodes located in the at least one path having a transmission range overlapped with that of an immediate adjacent node located in the at least one path, further comprising a node connected to the wired gateway, and an end node located at one end of the at least one path remote from the gateway-connected node, wherein each of a subset of the plurality of nodes, wherein said subset excludes the gateway connected node and the end node, operates in one of a first state in which a first node of the subset is ready to transmit a data frame, a second state at which a second node in the subset is prohibited from transmitting or receiving a data frame and a third state at which a third node in the subset is ready to receive a data frame.
Abstract:
The invention is directed to a method for receiving a feedback for at least a multicast broadcast service flow transmitting to a plurality of subscriber stations. The method comprises steps of assigning a plurality of code division multiple access (CDMA) codes to a feedback corresponding to the multicast broadcast service flow and then performing an allocation process for allocating a feedback channel for the subscriber stations. Thereafter, an announcement process is performed to announce a multiple feedback condition, the CDMA codes and the feedback channel to the subscriber stations. A channel monitoring process is performed for receiving a negative-acknowledgment (NACK)-based feedback sending from one of the subscriber stations unsatisfied with the multiple feedback condition and the NACK-based feedback is in a form of one of CDMA codes corresponding to the multicast broadcast service flow and is transmitted through the feedback channel.
Abstract:
A data transmission method with multiple token mechanism in wireless token ring protocol is provided. First, (a) a logical ring with M nodes is provided; (b) a k-th node is selected from the logical ring, and a token in the k-th node is generated; (c) a first message is sent to a (k+1)-th node from the k-th node with the token, and whether the (k+1)-th node responds a second message is judged, if yes, the data to be transmitted is transmitted from the k-th node, otherwise, the token of the k-th node is eliminated; (d) the token is sent to the (k+1)-th node from the k-th node after completing the transmission of the transmitted data of the k-th node, a generation token sequence is generated in a i-th node, and sent to a (i−1)-th node; and (e) the token is generated for the (i−1)-th node with the generation token sequence.