Abstract: A method and apparatus for scheduling, in real-time, the order in which data packets from multiple uplink channels are organized in a downlink channel of a satellite communications network. The satellite includes uplink and downlink channels for conveying data packets over channels between user terminals, ground stations and other user terminals. Queues in the satellite collect data packets from uplinks and output the data packets to the downlink using a bandwidth that is dynamically allocated. A scheduler allocates the bandwidth to at least one queue and continuously changes the amount of bandwidth allocated to each active queue while the queue is buffering data packets between the uplinks and downlink. The scheduler allocates bandwidth based upon a priority-class packet service schedule calculated based upon traffic parameters associated with each active queue.

Abstract: A downlink scheduler (20) is provided for scheduling the downlink transmission of data cells in a spot beam processing satellite (12). The downlink scheduler (20) includes a beam selector (48) for selecting one of the spot beams associated with the satellite (12), a plurality of wholesale selectors (50) for selecting one of a plurality of wholesalers, such that each of the wholesale selectors (50) is associated with one of the spot beams, and a plurality of retail selectors (52) for selecting one of a plurality of retail connections, such that each of the retail selectors (52) is associated with one of the wholesalers. Each of the selectors may use a packet fair queuing (PFQ) method to make its selection. The downlink scheduler (20) then passes at least one data cell from a selected retail connection to a downlink modulator (24), thereby scheduling the downlink transmission of data cells in the satellite.

Abstract: A method and apparatus for implementing multicast in a space-based communication system is disclosed. The present invention allows for the use of a buffer in which to store data packets prior to replication in a multicast application. The present apparatus includes a buffer (102), a header memory (103), and an ASIC (101) to store and extract received data packets and replicate them as required. The ASIC (101) includes a switch interface (201), a queue manager (203), a header processor (205), a holding buffer (207), and a arbitration interface (209). The switch interface (201) is connected to the queue manager (203). The queue manager (203) is connected to the buffer (102), the header processor 205, the holding buffer (207), and the arbitration and switch interface (204). The header processor (205) is connected to the header memory (103).

Abstract: The present invention is a method and apparatus for processing data packets in the outbound module of a space-based cell switch. The present invention uses an expanded set of queuing parameters to determine an output queue in which to store each data packet. The method includes the steps of selecting an expanded set of queuing parameters (202), establishing several output queues (204) based on combinations of the expanded set of queuing parameters, receiving data packets in a communications uplink (206), examining the header portion of each received data packet (208, 210 and 212), determining an appropriate output queue in which to store the data packet (214 and 216), and switching the received data packets to that appropriate output queue (218). The present apparatus includes several input modules (102), a switch control output (114) connected between the input module (102) and a switch fabric (104), and a several output modules (106) connected to the switch fabric (104).

Abstract: Techniques for trading satellite communication resources include a net work operations controller 80 for receiving an offer and analyzing bids in response to the offer. The network operations controller at least partially revises a downlink schedule of resources in response to the winning bid. A satellite 10 receives information from the network operations controller 80 and configures a switch 50 in the satellite, as well as the downlink schedule, in order to enable data communications through the satellite by the winning bidder.

Abstract: A mapping scheme that maps standard ATMs service classes (28) of the type used in a wired communications network into one of a plurality of available media access control channels (30) that allow the particular ATM service class (28) to be transmitted efficiently over the network, such as a satellite network. The various media access controlled channel types (30) reside in a media access control layer (24) between the ATM layer (22) and the physical layer (26). A predetermined uplink user protocol is assigned to each MAC channel 30 to efficiently transmit to the ATM cells on the satellite uplink.

Abstract: An onboard DAMA protocol for use in connection with a processing satellite communications network, where multiple users are assigned to a common transmission resource as part of a sharing set. A media access controller (30) on the satellite maintains a reservation log which identifies the frequencies and number of uplink time slots in the resource that are currently reserved by one or more members of the sharing set. To reserve a time-frequency slot on the transmission resource for a non-contentious transmission of data, a user of the sharing set will transmit a reservation request to the satellite on a contentious uplink resource. If a return message is not received, the user knows that the reservation request collided with another reservation request, and a retransmission strategy of the reservation request is employed.

Abstract: A method and device for extrapolating past signal-history data for insertion into missing data segments in order to conceal digital speech frame errors. The extrapolation method uses past-signal history that is stored in a buffer. The method is implemented with a device that utilizes a finite-impulse response (FIR) multi-layer feed-forward artificial neural network that is trained by back-propagation for one-step extrapolation of speech compression algorithm (SCA) parameters. Once a speech connection has been established, the speech compression algorithm device begins sending encoded speech frames. As the speech frames are received, they are decoded and converted back into speech signal voltages. During the normal decoding process, pre-processing of the required SCA parameters will occur and the results stored in the past-history buffer.