摘要:
A round off mechanism maintains a mean value of the operand while rounding twos complement binary data. Positive data values are incremented at the first discard bit prior to truncation of the discard bits, as are negative data values having a one within the most significant discard bit and at least one other discard bit. The discard bits are simply truncated for all other negative data values.
摘要:
A system for improved ghost cancellation for use in particular in television receivers. The system featuring a superior ghost cancellation reference (GCR) signal which exhibits improved performance in noisy environments and which exhibits the flat and wide bandwidth necessary for effective channel characterization which also exhibiting a higher and more evenly distributed amplitude versus time characteristic than that provided by known, non-cyclic ghost cancellation signals. The GCR signal is encoded a selected television line of an eight field sequence of lines however the polarity of the GCR signal is reversed selectively from field to field prior to inserting it in respective television lines. At a decoder or television receiver incorporating the invention, the selected television lines are combined in a manner which provides for both a robust received GCR value and cancellation of the effects of pair-wise constant television line signals on the GCR signals.
摘要:
A method and system for sharing files between a group of computer systems. The file sharing system allows a group of computer systems to be defined. The files shared by a group are associated with a group folder. A group folder is represented by a folder created by the file system of each member of the group. The folder at each member contains a file for each file that is shared by the group. The files in the folder of a member may be actual files stored at that member, which contains the content of the shared file, or virtual files identifying the actual file that is stored at another member. When a member accesses a virtual file, the file sharing system detects the access and requests that the file owner provide a copy of the file to the accessing member on a peer-to-peer basis. Whenever a shared file is modified, the file owner sends updated metadata for that file to the other members of the group.
摘要:
An apparatus for receiving a television signal containing a ghost cancellation reference signal, and for using the reference signal to process the television signal so as to substantially eliminate path induced distortion.
摘要:
A system for improved echo cancellation for use in particular in television receivers. The system features a superior ghost cancellation reference signal which exhibits improved performance in noisy environments and which exhibits the flat and wide bandwidth necessary for effective channel characterization while exhibiting a higher and more evenly distributed amplitude versus time characteristic than that provided by known, non-cyclic ghost cancellation signals.
摘要:
A method and apparatus for improved ghost cancellation for use in particular in television receivers. The sequence of coefficients derived from a received GCR (Ghost Cancellation Reference) signal, is further processed to effect a transfer of energy from minor echo coefficients to major echo coefficients thereby improving the overall performance of the ghost cancellation device.
摘要:
A free-running sample rate converter and a large spanning, non-linear pre-equalizer are employed before a timing recovery loop within a wireless receiver chain, while forward and feedback equalization after the timing recovery loop (at and around the input of a sync detector) is also retained. A channel identifier produces a channel estimate from the PN511 training sequence within the received wireless signals, with the pre-equalizer employing the resulting channel estimate to equalize the received signals being passed to the timing recovery loop, improving the signal quality for carrier and timing recovery and decoding to increase the probability of successful decoding while enabling the use of fast tracking forward and feedback equalizers for decoding.
摘要:
A novel echo cancellation reference (“ECR”) training signal is inserted into the current ATSC 8 VSB data stream to achieve improved echo rejection while maintaining compatibility with the ATSC 8 VSB digital ATV standard. The novel ECR training signal is also suitable for other multipath or dispersive digital communication channels. A pre-equalization subsystem is included in the digital ATV system as a front end to the VSB receiver, and is trained with preferably the novel ECR training signal. One type of pre-equalization subsystem provides a fully ATSC compliant signal at its output, and therefore is particularly useful with standard VSB receivers. Another type of pre-equalization system provides a signal at its output which is ATSC compliant in some respects but which retains the ECR signal, and therefore is particularly useful for signal relays, analysis purposes, and other applications in which the residual channel information is important.
摘要:
A multiplierless digital FIR filter comprising a plurality of serially cascaded stages providing a non-linear series of two to the Nth power coefficient values, and in which quantization error is reduced by scaling the coefficient values to minimize root mean square error. Each stage includes a basic unit and an incremental unit, the basic unit providing two shift operations and including a delay element and an adder. To achieve a particular quantization error, one or more incremental units are connected in series with the basic unit in each stage, each such incremental unit providing a single shift operation and including a delay element and an adder. The number of incremental units in each stage and the number of cascaded stages can be selected to achieve a filter having desired performance characteristics and which can be realized on a VLSI chip.
摘要:
A color television receiver, having a tuner and associated demodulation circuits for both a main picture signal and a picture-in-picture (PIP) signal, uses a single memory for synchronization and for storing a single subsampled field of the PIP signal. Appropriate circuitry is included to selectively adjust the output of the memory to prevent the possible disorder of lines of the resultant PIP signal on display.