Abstract:
An apparatus includes a first signal interface configured to couple a signal to and from a coaxial cable, a second signal interface configured to couple a signal to and from a power line, and signal coupling circuitry configured to pass a communication signal between the first signal interface and the second signal interface.
Abstract:
A method of operating in a network in which stations communicate over a shared medium is described. The method provides regularly repeated contention free intervals, CSMA communication during times outside the contention free intervals, and distributed control over the initiation and makeup of the contention free intervals to a plurality of stations so that any of the plurality of stations can independently initiate transmission within the contention free interval.
Abstract:
A robust Media Access Controller, MAC, scheme for network stations (12) operating in an OFDM transmissions network (10). The MAC scheme uses robustly transmitted frame control information to ensure network synchronization for media access. The frame control information can occur in a frame (80) in a first frame control field (98) before the frame's payload (82) and in a second frame control field (102) after the frame's payload (82), or in a third access priority (144) to convey channel access prioritization for QoS.
Abstract:
A partial ARQ protocol for multicast and broadcast transmissions in network devices (12) operating in a shared medium access network (10). To support the partial ARQ, a media access control (MAC) protocol uses robustly transmitted frame delimiters (90) and MAC management frame information (182). In a multicast or broadcast frame (80) with partial ARQ, a destination address field (108) is set to that of a selected proxy device's address, and the address of the intended recipients (of group address of the intended recipients) is placed in a Multicast with Resonse entry 210H in the MAC management frame information (182). The frame (80) also contains a multicast flag (164) set to indicate that the transmission is intended for more than one device and a value in a delimiter type field (132) to indicate that a response is requested. Upon receipt of such a frame, the proxy device specified by the destination address field (108) provides an appropriate response type on behalf of the group. Then on-proxy recipients, detecting the multicast flag setting, know to ignore the DA in the destination address field (108) and instead look to the MAC management entry 210H for actual destination addresses.
Abstract:
A mechanism (80) for determining phases of a symbol for phase correlation is provided. The mechanism (80) performs a symmetric apodizing window function on a symbol sample of a symbol having a symbol period of T and a time-offset symbol sample offset from the symbol sample by T/2 to produce first windowed values for the symbol sample and second windowed values for the time-offset symbol sample. The mechanism (80) applies a time shift to re-align the time-offset symbol sample with the symbol sample and sums the second windowed values and the corresponding first windowed values. The summed values are then converted to phases. The symmetric apodizing window function is an apodizing window function having the property Wj + W(FFTSize/2+j)= constant, where FFTSize is the size of the FFT sample. The symmetric apodizing window function, such as a Hanning window, may be performed in the time of frequency domain.
Abstract:
Coupling a charging station to a power line segment that is terminated at a first end by a charging terminal includes: sensing a communication signal propagating on the power line and being coupled from multiple taps connected to the power line segment, and determining if the communication signal is propagating on the power line segment in the direction from the first end to a second end of the power line segment or in the direction from the second end to the first end.
Abstract:
In a network, some data are transmitted between stations during time slots in contention free periods. Selecting the time slots includes collecting timing information at some stations in the network. The timing information indicates the times of existing time slots used by stations whose transmissions can be reliably received by the station collecting the timing information. The timing information is distributed to other stations in the network. A new time slot for transmission between a first and a second station is selected based at least on timing information indicating the times of existing time slots used by stations whose transmissions can be reliably received by at least one of the first and second station. The method is preferably a Broadband Power Line Network (BPLN) which comprises a Head End station (HE) and a plurality of Repeaters (Rl, R2). TDMA schedule information is transmitted in beacons.
Abstract:
A method for establishing shared information is described. The method includes estimating characteristics of a communication channel between two nodes based on signals transmitted between the nodes. The method also includes transmitting a signal from the first node to the second node, the signal being modulated with a first data sequence according to a first estimated characteristic, and transmitting a signal from the second node to the first node, the signal being modulated with a second data sequence according to a second estimated characteristic. Shared information is formed at each of the first and second nodes based on at least a portion of the first data sequence and at least a portion of the second data sequence.
Abstract:
A scheme for supporting both centralized and distributed shared medium access control in a CSMA network (700). A master device (702) exchanges connection control messages with a slave device (704) using contention-oriented access to establish a connection and a session of periodic contention-free intervals. The contention-free intervals (722) alternate with contention-oriented intervals (725) according to the timing parameters specified by the connection control massages. Each of the contention-free intervals (722) is divided into slots (727), the master device (702) transmitting a downstream frame and the slave device (704) transmitting an upstream frame in a following slot if the downstream frame indicates the following: a source address matching that of the master device, a contention-free access at a highest priority and a connection number corresponding to the connection established between the master device and the slave device. Master control is passed from one device to another device during the contention-free interval using a master flag for to indicate which device has master control and a control flag to indicate the direction in which master control is being passed.