摘要:
An apparatus and method for encoding low-density parity check codes. Together with a repeater, an interleaver and an accumulator, the apparatus comprises a precoder, thus forming accumulate-repeat-accumulate (ARA codes). Protographs representing various types of ARA codes, including AR3A, AR4A and ARJA codes, are described. High performance is obtained when compared to the performance of current repeat-accumulate (RA) or irregular-repeat-accumulate (IRA) codes.
摘要:
The present invention includes a technique for updating messages that originate at the constraint nodes of bi-partite graphs in Low Density Parity Check codes. The technique computes only two outgoing magnitudes at each constraint node and exhibits no measurable performance loss as compared to exact belief propagation which computes a unique magnitude for each departing edge from a given constraint node. The technique eliminates the need for memory based table look-up in the constraint node processing and has been implemented, in one embodiment, using only shift, add, and comparison operations.
摘要:
A method of forming a continuous band of resilient material with a preselected design on an exterior surface thereof, which has a seamless appearance is disclosed. The method includes inserting a molding insert core having a textured outer surface within a molding cavity. A continuous band of resilient material is formed about the core. The band bears the reverse image of the textured pattern on its interior surface. Like other molding processes, the band bears flash or parting lines formed on its exterior surface. The band is inverted by turning it inside out so that the flash or parting lines are positioned on its interior surface and the reverse of the textured pattern is positioned on its exterior surface. As such, an aesthetically pleasing band having a seamless exterior surface is produced.
摘要:
An improved cigarette lighter adapter for an electronic device has an exterior flexible covering that provides a textured surface for gripping by the user to facilitate the insertion and removal of the adapter from a cigarette lighter socket. The adapted also includes a pair of ground contacts in the form of spring members that abut ground contact pads on an internal circuit board. The ground contacts are biased in place within the adapter against the circuit board contact pads in a solderless manner. The ground contacts are positioned in alignment with each other on opposite sides of the circuit board so that contact forces they exert on the circuit board balance so as not to apply any detrimental stress to the circuit board.
摘要:
A continuous and uninterrupted process for knitting a plurality of cylindrical blanks, automatically transferring the knit blanks sequentially to a shrink apparatus, continuously shrinking the blanks for a predetermined period of time, and automatically transferring the shrunken blanks from the shrink apparatus to a remote location. The invention also includes an apparatus for carrying out the process having a shrink apparatus with a blank input conduit, a blank output conduit, a plurality of heating chambers, and means for transferring knitted tubular blanks from knitting machines to heating chambers. A heat source transfers heat to the heating chambers to heat and shrink the blanks, and an associated component automatically transfers the shrunken blanks to a remote location. The apparatus also includes an indexer carrying the heating chambers, appropriate conduit means for directing incoming and exhausting outgoing heated air, and a programmable controller for selectively displacing the indexer to coordinate the operation of the heat source with the other components of the apparatus.
摘要:
Communication systems are described that use signal constellations, which have unequally spaced (i.e. ‘geometrically’ shaped) points. In many embodiments, the communication systems use specific geometric constellations that are capacity optimized at a specific SNR. In addition, ranges within which the constellation points of a capacity optimized constellation can be perturbed and are still likely to achieve a given percentage of the optimal capacity increase compared to a constellation that maximizes dmin, are also described. Capacity measures that are used in the selection of the location of constellation points include, but are not limited to, parallel decode (PD) capacity and joint capacity.
摘要:
Communication systems are described that use signal constellations, which have unequally spaced (i.e., ‘geometrically’ shaped) points. In many embodiments, the communication systems use specific geometric constellations that are capacity optimized at a specific SNR. In addition, ranges within which the constellation points of a capacity optimized constellation can be perturbed and are still likely to achieve a given percentage of the optimal capacity increase compared to a constellation that maximizes dmin, are also described. Capacity measures that are used in the selection of the location of constellation points include, but are not limited to, parallel decode (PD) capacity and joint capacity.
摘要:
A shipping container is constructed for shipping channeled fuel bundle assemblies. The shipping container includes an outer container, an inner container sized to fit within the outer container, and shock absorbing material disposed at least between the outer and inner containers. The inner container is shaped to house at least one pre-channeled fuel bundle assembly including a channel, a channel fastener, and an array of fuel rods supported by grid spacers between an upper tie plate and a lower tie plate. The inner container includes a lower tie plate restraint device shaped to receive the lower tie plate and a lower portion of the channel, and an upper tie plate restraint device shaped to receive the upper tie plate and an upper portion of the channel and channel fastener assembly. The lower and upper tie plate restraint devices are lockable within the inner shipping container.
摘要:
Communication systems are described that use signal constellations, which have unequally spaced (i.e. ‘geometrically’ shaped) points. In many embodiments, the communication systems use specific geometric constellations that are capacity optimized at a specific SNR. In addition, ranges within which the constellation points of a capacity optimized constellation can be perturbed and are still likely to achieve a given percentage of the optimal capacity increase compared to a constellation that maximizes dmin, are also described. Capacity measures that are used in the selection of the location of constellation points include, but are not limited to, parallel decode (PD) capacity and joint capacity.
摘要:
Communication systems are described that use geometrically shaped constellations that have increased capacity compared to conventional constellations operating within a similar SNR band. In several embodiments, the geometrically shaped is optimized based upon a capacity measure such as parallel decoding capacity or joint capacity. In many embodiments, a capacity optimized geometrically shaped constellation can be used to replace a conventional constellation as part of a firmware upgrade to transmitters and receivers within a communication system. In a number of embodiments, the geometrically shaped constellation is optimized for an Additive White Gaussian Noise channel or a fading channel.