摘要:
Techniques are provided for reliably distributing network management information in and ad hoc multi-hop wireless network which includes a number of existing nodes. A first node selects a particular timeslot in a dedicated channel based on the network management information received from the neighbor nodes and determines, via a contention channel, if the particular timeslot is being used by any neighbor nodes of the first node. If the particular timeslot is determined to be unused, then it is assigned to the first node for periodically transmitting network management information.
摘要:
A first time division multiplex (TDM) time slot is provided which is defined as a bi-directional channel for use in a TDM network including a source node and a destination node. The source node can transmit data to the destination node in a first portion of a first TDM time slot. In one implementation, a second portion of the same first TDM time slot can be reserved for the destination node to transmit information to the source node. The destination node can determine whether the data from the source node has arrived properly, and then transmit an indication message to the source node in the second portion of the same first TDM time slot to indicate whether the data from the source node has arrived properly at the destination node.
摘要:
A system and method for transmitting packets in a network (100). A node (102, 106, 107) in the network (100) accesses uses one of a plurality of medium access techniques for transmitting packets on the network (100). The node (102, 106, 107) separates packets to be transmitted into classes based on at least one characteristic of the packets and selects one of the medium access techniques for each class of packets based on whether the medium access technique provides improved transmission efficiency for the at least one characteristic of the packets in the class. The node (102, 106, 107) transmits the packets in each respective class using the respective selected medium access technique.
摘要:
An apparatus and method for use with a shared access communication channel is disclosed. A wireless network device receives signals and recovers data from a first plurality of subscriber units and a second plurality of subscriber units in a time interval. Received signals from the first plurality of subscriber units are distinguishable by having unique pseudo noise (PN) sequence with respect to others of the first plurality of subscriber units. Received signals the second plurality of subscriber units are distinguishable by a unique orthogonal sequence with respect to others of the second plurality of subscriber units. Received signals are distinguished between the first and second plurality of subscriber units based on detection of an orthogonal sequence present only in the received signals from the second plurality of subscriber units.
摘要:
The present invention provides a bandwidth efficient system and method of measuring the range between nodes (102, 106, 107) in a wireless communications network (100) with one-way data transfer, where each node (102, 106, 107) periodically transmits a message that contains information regarding neighboring nodes (102, 106, 107) from which any prior messages have been received by the transmitting node (102, 106, 107). A node (102, 106, 107) receives the messages transmitted from neighboring nodes (102, 106, 107) in the network (100), and records the times of arrival of the received messages. The node (102, 106, 107) receiving those messages can thus determine the respective distances between itself and the neighboring nodes (102, 106, 107) based on the respective time of arrivals of the received messages and the respective information included in the respective messages.
摘要:
Method and apparatus for base stations and subscriber units allows soft handoff of a CDMA reverse link utilizing an orthogonal channel structure. Subscriber units transmit an orthogonally coded signal over a reverse link to the base stations. A given base station provides timing control of the timing offset of the reverse link signal. Based on at least one criterion, an alignment controller determines that the given base station should hand off timing control to another base station, and a soft handoff process ensues. In response to a command or message for soft handoff of the subscriber unit from the given base station to another base station, the subscriber unit makes a coarse timing adjustment to the timing of the coded signal. The subscriber unit may make fine timing adjustments based on feedback from the base station controlling timing. Multiple base stations may provide power control feedback to the subscriber unit.
摘要:
Techniques are provided for communicating a data stream in a wireless communication network. A source divides the data stream into a first data sub-stream and a second data sub-stream. The first data sub-stream can be modulated using a first modulation technique to generate a first modulated data sub-stream, and the second data sub-stream can be modulated using a second modulation technique to generate a second modulated data sub-stream. A destination receives the first data sub-stream over a first frequency band, and receives the second data sub-stream over a second frequency band. The destination demodulates the first data sub-stream using a first demodulation technique to generate a first demodulated data sub-stream, and demodulates the second data sub-stream using a second demodulation technique to generate a second demodulated data sub-stream. The destination then combines the first demodulated data sub-stream and the second demodulated data sub-stream to generate the data stream.
摘要:
A system and method for cognitive communication device operation. In accordance with the system and method, a node (102, 106, 107) that communicates in a wireless multihopping communication network (100) uses a receiver (302, 402, 502, 602) to acquire a digital sample of a communication signal, and extracts at least one feature of the digital sample. The node (102, 106, 107) employs a classifier (306, 406, 506) to determine the signal type, and a transmitter (108) to send feature vectors including information representing the signal type to other nodes (102, 106, 107) in the network (100).
摘要:
A method for measuring the time of arrival of radio signals within a network comprises receiving the received signals including at least a first pseudorandom code and a second pseudorandom code from at least one other node; identifying a frequency difference between the node and the other node using a phase difference between each of a maximum value of a cross-correlation provided by the first pseudorandom code and the second pseudorandom code; applying the frequency difference to the reception of the received signal; and calculating the time of arrival of the received signal comprising a time, measured with a local clock, when the cross-correlation has achieved the maximum value.
摘要:
An apparatus for use with a shared access communication channel is disclosed. The chipping rate of a first group of terminals is determined. Transmissions on the shared access communication channel are encoded using first pseudorandom noise (PN) code and a phase shift at the first chipping rate and an orthogonal spreading code having a chipping rate less than the first chipping rate. The apparatus may receive a feedback channel assignment and may receive an indication of a change in timing on the assigned feedback channel.