摘要:
A method for spectrally shaping a communication signal is provided. The method comprises generating a plurality of spreading codes, assigning a probability to each of the plurality of spreading codes, and modulating the communication signal by hopping between the plurality of spreading codes such that a time-average proportion of time spent using any one of the plurality of spreading codes is equal to the probability assigned to that spreading code.
摘要:
A method for scheduling a computation for execution on a computer with a number of interconnected functional units. The computation is representable by a data-flow graph with a number of nodes connected by edge. A loop-period of the computation is calculated and the nodes are scheduled for throughput by assigning an execution cycle and a functional unit to each node of the data-flow graph. The scheduling of flexible nodes is adjusted to minimize the number of interconnections required in each execution cycle. The edges of the data-flow graph are allocated to one or more of the interconnections between functional units. The scheduling method may be used, for example, to optimize the interconnection fabric design for an ASIC or as part of a compiler for a re-configurable streaming vector processor.
摘要:
A memory interface device (100) providing a fractional address interface between a data processor (104) and a memory system (102) and a method for retrieving intermediate data values from a memory system using fractional addressing. The device includes an address generator (108) for generating first and second memory addresses, the first memory address being less than or equal to a specified fractional address, the second memory address being greater than or equal to the fractional address. The device also includes a memory access unit (110) coupled to the address generator (108) for retrieving first and second data values from the memory system (102) at the first and second memory addresses, respectively. The device also includes a data access unit (112) for interpolating between the first and second data values and passing the interpolated value to the data processor (104). The memory interface has application in a variety of data processing systems, including digital signal processors and streaming vector processors.
摘要:
A fax selective call receiver system (10) featuring compression of a fax message with an optimal one of a plurality of compression code-books (50). At least a portion (44) of a source document (26) is compressed with each of a plurality of code-books (50) and the smallest resulting data file is selected as the optimal compressed file. The compressed data file is transmitted to a selective call receiver (40) together with an index identifying the optimal code-book. The selective call receiver (40) stores each of the plurality of code-books and accesses the particular code-book for decompressing the data file on the basis of the received index. In an alternative embodiment, the fax message is divided into composing segments (SI1, SI2 and SI3) and each segment is compressed with each code-book to determine the optimal code-book for each segment.
摘要:
A selective call communication system (10) has a scanner (14) for retrieving information from a source document (26). The source document (26) includes a region of interest (42) formatted in at least two format regions (50, 52, 54). The at least two format regions (50, 52, 54) include a first format region (50, 52) designated for a first type information, and a second format region (54) designated for a second type information. The scanner (14) further includes an encoder (708) for encoding and compressing the information; and a modem (710), coupled to the encoder (708), for transferring the information to a selective call terminal (28). The selective call terminal (28) has a receiver (202) for receiving the information; and a processor (20), coupled to the receiver (202), for processing the information. The processor (20) further comprises a first encoder (214) for encoding and compressing the first type information according to a first encoding and compression technique; and a second encoder (224) for encoding and compressing the second type information according to a second encoding and compression technique. A transmitter (30), coupled to the processor (20), transmits the information being processed to an at least one selective call receiver (40).
摘要:
A method and apparatus for allocating resources to a node in an ad-hoc communication system is provided herein. During operation, nodes of the system will receive resource allocations from their parent node. The resource allocation comprises a portion of available resources that may vary in size. Each node will determine the resource needs for its children nodes only and then dynamically assign resources to them. The resources assigned to the children nodes comprise a portion of the resources assigned to the node by its parent node. Additionally, knowledge as to how the children further allocate resources to their own children is not known by the parent, however, the children nodes must allocate a portion of their resource to their children nodes.
摘要:
A method and apparatus to facilitate managing communications with at least one wireless node (102, 103) having an outbound payload memory in a severely resource-constrained wireless network (100) can provide for a coordinator node (101) for that network providing (201) information regarding remaining capacity of those outbound payload memories and then automatically using (202) that information in integral combination with a bandwidth allocation management process to control allocation of at least one wireless communication resource by which the wireless nodes can transmit items contained in the outbound payload memory.
摘要:
A method and apparatus that allocates bandwidth among wireless sensor nodes in wireless sensor groups in a wireless sensor network (WSN) is disclosed. The method may include forming a plurality of wireless sensor node groups from a plurality of wireless sensor nodes based on battery levels of the wireless senor nodes, allocating transmission time slots for the wireless sensor nodes in each of the wireless sensor node groups based on at least one channel quality metric, determining average battery levels for each of the wireless sensor node groups and average battery level of all of the wireless sensor nodes, determining differences between the average battery levels of each of the wireless sensor node groups and the average battery level of all of the wireless sensor nodes, wherein if any difference in the average battery levels is above a predetermined threshold, regrouping the plurality of wireless sensor nodes according to the battery levels of the plurality wireless sensor nodes to minimize any variance in average battery level across all of the wireless sensor node groups.
摘要:
A system includes a first gas sensor [110] to detect a first concentration of a predetermined gas and to determine a first rate of change in the first concentration over a time interval. A second gas sensor [115] detects a second concentration of the predetermined gas and determines a second rate of change in the second concentration over the time interval. A third gas sensor [120] detects a third concentration of the predetermined gas and determines a third rate of change in the third concentration over the time interval. The first, second, and third gas sensors each have a known location. At least one processing device [510] (a) determines respective distances between a gas leak location and the respective locations of the gas sensors based on the detected rates of change, and (b) calculates a location of the gas leak based on a triangulation of the first distance, the second distance, and the third distance.
摘要:
An electronic greeting card communication system (100) includes a first personal communicator (102), an electronic mail server (136), and a second personal communicator (102). The first personal communicator accepts off-line selection of an electronic greeting card from a user (502), and then transmits a request message corresponding to the off-line selection. The electronic mail server (136) receives the request message and then wireless transmits an electronic greeting card message to the second personal communicator (102) and updates billing information (620) for billing the user of the first personal communicator (102). The second personal communicator (102) selectively receives the wireless transmitted electronic greeting card message and presents it to a user.