摘要:
A communications receiver system is presented for detecting burst errors and providing erasure information to a block decoder, thereby effectively doubling the conventional correction capability of the block decoder with only a minimal increase in complexity. In one embodiment, the receiver includes a demodulator which includes circuitry to detect error bursts in the received symbol sequence. Once detected, the locations of symbols in error are marked in the form of erasure flags. An error correction decoder is then able to correct up to twice as many errors with the additional information provided by the erasure flags.
摘要:
A communications receiver system is presented for detecting burst errors and providing erasure information to the block decoder (outer decoder), thereby effectively doubling the conventional correction capability of the block decoder with only a minimal increase in complexity. In one embodiment, this mechanism takes the form of a circuit which re-encodes the output of the inner decoder, compares it with the received sequence of code symbols, and flags a portion of the inner decoder output for erasure when an excessive number of code symbol errors are detected. In a second embodiment, this mechanism takes the form of a circuit which makes hard symbol decisions on the channel signal, compares the hard decisions to the channel signal to determine a noise level, and thereafter flags the channel output in regions with excessive noise levels.
摘要:
A communications receiver system is presented for detecting burst errors and providing erasure information to the block decoder, thereby effectively doubling the conventional correction capability of the block decoder with only a minimal increase in complexity. In one embodiment, this mechanism takes the form of a circuit which re-encodes the output of the inner decoder, compares it with the received sequence of code symbols, and flags a portion of the inner decoder output for erasure when an excessive number of code symbol errors are detected. In a second embodiment, this mechanism takes the form of a circuit which makes hard symbol decisions on the channel signal, compares the hard decisions to the channel signal to determine a noise level, and thereafter flags the channel output in regions with excessive noise levels.
摘要:
Disclosed are a method, system and/or device of continuous barcode tape based inventory location tracking. In one aspect, a method includes analyzing a layout diagram of a distribution center. The method further includes determining that the layout diagram includes a shelf. A number of segments associated with the shelf based on a forecasted allocation of an inventory on the shelf are calculated. A bar code tape having a globally unique identifier (GUID) associated with each segment of the number of shelves is automatically generated using a processor and a memory of a central inventory tracking system.
摘要:
Disclosed are a system, device and/or an apparatus of modular hanging lasers to enable real-time control in a distribution center. In one embodiment, a laser assembly, includes a first support member having a curved upper hook, a second support member having the curved upper hook, and a printed circuit board in between the first support member and the second support member: (1) that is physically coupled with the first support member at a first rotation point of the printed circuit board, and which is physically coupled with the second support member at a second rotation point of the printed circuit board. The laser assembly is attached to a first wire of a distribution center above at least one row of the distribution center having at least one of a shelving, an inventory, and storage compartments along at least one row.
摘要:
A method of transmitting data in a cable modem system includes the steps of encoding the data using forward error correction. The data is then encoded with Turbo encoding. The data is then sent to a modulation scheme. The data is then transmitted over a cable channel. The data is then demodulated. The data is then decoded using a Turbo decoder. An inverse of the forward error correction is then applied to the data.
摘要:
An inexpensive synchronous detection module is disclosed for a sideband signal receiver that provides for flexibility in design of the tuner. The detection module is adaptable to detection of upper or lower sideband signals. One embodiment includes an analog-to-digital converter, a Hilbert transform filter, a sideband selection switch, a complex multiplier, a carrier recovery. loop, a matched filter, and a decimator. The analog-to-digital converter oversamples an intermediate frequency (IF) signal from the tuner, and the Hilbert transform filter generates a Hilbert transform of the digital IF signal. An analytic IF signal can be generated from the digital IF signal by multiplying the Hilbert transform of the digital IF signal by j(=sqrt(−1)), and adding the resulting imaginary-valued signal to the digital IF signal. The sideband selection switch can “flip” the analytic IF signal by inverting the imaginary-valued signal. The complex multiplier multiplies the analytic IF signal by a complex-value sinusoid to shift the analytic IF signal to baseband. The resulting analytic baseband signal is match filtered and decimated to form a baseband double sideband signal with one sample per symbol period. The carrier recovery loop operates on the imaginary part of the analytic baseband signal to generate the complex sinusoid that shifts the analytic IF signal to baseband.
摘要:
Disclosed are a system, device and/or an apparatus of modular hanging lasers to enable real-time control in a distribution center. A laser assembly includes a first support member and a second support member having a curved upper hook. The laser assembly includes a printed circuit board in between the first support member and the second support member that is physically coupled with the first support member at a first rotation point of the printed circuit board and the second support member at a second rotation point of the printed circuit board. The printed circuit board has a laser whose orientation is adjustable when a protrusion of the printed circuit board extends from a curved guide of the first support member. The second support member is manually adjusted by shifting the protrusion along the curved guide based on a graduation indicator adjacent to the curved guide.
摘要:
Satellite communications are carried out using the Data Over Cable Interface Specification (DOCSIS). Satellite modems are notified of upstream channel congestion by inserting a congestion notification message in a medium access protocol (MAP) message for the upstream channel. Specifically, the congestion notification message is inserted in an unused field of the MAP message, such as the explicit congestion notification (ECN) field. The MAP message can also carry other characteristics of the upstream channel, including priority threshold, multicast access burst availability, and available bandwidth.
摘要:
A system and method for providing upstream adaptive modulation. Burst parameters associated with a range of data interval usage codes (IUCs) are defined. Each of the data IUCs has a different modulation order and forward error correction (FEC). The SNR and codeword error rate for each satellite modem in the network are monitored. The data IUCs are dynamically assigned to different satellite modems within an upstream channel based on SNR and/or codeword error rate to enable each of the satellite modems in the upstream channel to achieve maximum bandwidth efficiency during upstream data transmissions. Bandwidth requests are received from the satellite modems and granted. The grant includes the assigned data IUC. The data bursts received in the upstream channel are each processed using the parameters from the assigned IUC for each of the satellite modems sending data in the upstream channel. When any of the satellite modems' SNR and/or codeword error rate changes, the data IUC for that satellite modem is changed accordingly.