1. A method for decoding a check code, the method comprising:
receiving, at a check node, a plurality of variable messages, wherein individual ones of the plurality of variable messages are received from respective variable nodes, and wherein the individual ones of the plurality of variable messages include a magnitude based, at least in part, on a value stored at the respective check node and a weight associated with the value;
counting a first number of the plurality of variable messages having a first weight;
counting a second number of the plurality of variable messages having a second weight; and
computing a parity check function based, at least in part, on the first and second numbers.
2. The method of claim 1, wherein the magnitude is a quantized magnitude based on the value stored at the respective check node, and wherein the weight is based, at least in part, on a difference between the quantized magnitude and the value.
3. The method of claim 1, wherein individual ones of the plurality of variable messages comprise a product of the corresponding magnitude and the corresponding weight.
4. The method of claim 1, wherein the first and second weights are selected from a group of predetermined weights.
5. The method of claim 1, further comprising calculating at least one check node output message based, at least in part, on the parity check function, and wherein the at least one check node output message has a magnitude selected from a predetermined group of magnitudes.
6. The method of claim 1, wherein said computing a parity check function comprises:
checking a parity check condition for the check node; and
establishing a check node confidence for the check node.
7. The method of claim 6, wherein said checking a parity check condition comprises determining whether the magnitudes included in the plurality of variable messages satisfy a parity check condition for the check node.
8. The method of claim 7, wherein said computing a parity check function comprises computing the parity check function in a first manner if the parity check condition is satisfied and computing the parity check function in a second manner if the parity check condition is not satisfied.
9. The method of claim 1, wherein the first weight corresponds to a weak variable message, and wherein the method further comprises providing a neutral check node output message if the first number of the plurality of variable messages is two or more.
10. The method of claim 6, wherein the first weight corresponds with a weak variable message, wherein the second weight corresponds with a medium variable message, and wherein the method further comprises providing a strong check node output message reinforcing a status quo if the first and second number of the plurality of variable messages are zero and the parity check condition is satisfied.
11. The method of claim 6, wherein the first weight corresponds with a weak variable message, and wherein the method further comprises providing a weak check node output message indicating bit flipping if the first number is zero and the parity check condition is violated.
12. The method of claim 6, wherein the first weight corresponds with a weak variable message, wherein the second weight corresponds with a medium variable message, and wherein the method further comprises providing a weak check node output message reinforcing a status quo if the first number is zero, the second number is two or greater, and the parity check condition is satisfied.
13. The method of claim 6, wherein the first weight corresponds with a weak variable message, wherein the second weight corresponds with a medium variable message, and wherein the method further comprises providing a weak check node output message reinforcing a status quo if the first number is one, the second number is one or more, and the parity check condition is satisfied.
14. The method of claim 6, wherein the first weight corresponds with a weak variable message, wherein the second weight corresponds with a medium variable message, and wherein the method further comprises providing a weak check node output message indicating bit flipping if the parity check condition is violated, the first number is one, and the second number is one or more.
15. The method of claim 6, wherein the first weight corresponds with a weak variable message, wherein the second weight corresponds with a medium variable message, and wherein the method further comprises providing a strong check node output message indicating bit flipping if the parity check condition is violated, the first number is one, and the second number is zero, wherein the strong check node output message is provided to a variable node associated with the weak variable message, and wherein the method further comprises providing weak check node output messages indicating bit flipping to variable nodes associated with other of the plurality of variable messages.
16. The method of claim 6, wherein the first weight corresponds with a weak variable message, wherein the second weight corresponds with a medium variable message, and wherein the method further comprises providing a strong check node output message reinforcing a status quo if the parity check condition is satisfied, the first number is one, and the second number is zero, wherein the strong check node output message is provided to a variable node associated with the weak variable message, and wherein the method further comprises providing weak check node output messages reinforcing the status quo to variable nodes associated with other of the plurality of variable messages.
17. The method of claim 6, wherein the first weight corresponds with a weak variable message, wherein the second weight corresponds with a medium variable message, wherein the method further comprises providing a strong check node output message reinforcing a status quo if the parity check condition is satisfied, the first number is zero, and the second number is one, wherein the strong check node output message is provided to a variable node associated with the medium variable message, and wherein the method further comprises providing medium check node output messages reinforcing the status quo to variable nodes associated with other of the plurality of variable messages.
18. A decoder comprising:
a plurality of variable nodes, each variable node configured to generate a variable message; and
a plurality of check nodes, each check node coupled to a respective set of the plurality of variable nodes and configured to receive a plurality of variable messages generated by the respective set of the plurality of variable nodes, wherein individual ones of the plurality of variable messages include a magnitude based, at least in part, on a value stored at the respective check node and a weight associated with the value, and wherein each check node is further configured to:
count a first number of the plurality of variable messages having a first weight;
count a second number of the plurality of variable messages having a second weight; and
compute a parity check function based, at least in part, on the first and second numbers.
19. The decoder of claim 18, wherein the decoder comprises a processor.
20. The decoder of claim 19, wherein the processor is implemented in hardware, software, or combinations thereof.
21. The decoder of claim 18, wherein each check node is further configured to provide respective check node output messages to the respective set of the plurality of variable nodes, and wherein the check node output messages have a strength based, at least in part, on the first and second numbers.
22. The decoder of claim 18, wherein the magnitude is a quantized magnitude based on the value stored at the respective check node, and wherein the weight is based, at least in part, on a difference between the quantized magnitude and the value.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. Shaft preheater with
a plurality of shafts (2a, 2b, . . . ) for receiving lumpy material (4),
an arrangement (3) for filling the individual shafts with the lumpy material to be preheated
and also means (9) for limiting the layer height in the shafts, the said means (9) being constructed in such a way that a separate adjustment of the layer height is provided at least in some shafts (2a, 2b, . . . ),
characterised in that the means (9) for limiting the layer height have an arrangement (90) for coarse adjustment and an arrangement (91) for fine adjustment of the layer height.
2. Shaft preheater as claimed in claim 1, characterised in that separate means (9) for limiting the layer height are provided in all shafts.
3. Shaft preheater as claimed in claim 1, further characterised by a feed bin (1) through which the individual shafts are filled with lumpy material, the feed bin being divided into individual sectors.
4. Shaft preheater as claimed in claim 1, characterised in that the means (9) for limiting the layer height comprise a slide plate (90).
5. Shaft preheater as claimed in claim 1, characterised in that the means (9) for limiting the layer height comprise a slide plate (90) which can be introduced from above into the corresponding shaft and of which the lower edge (90a) serves for limiting the layer height.
6. Shaft preheater as claimed in claim 1, characterised in that the means (9) for limiting the layer height comprise a needle valve (91).
7. Shaft preheater as claimed in claim 1, characterised in that the means (9) for limiting the layer height comprise a needle valve (91) which can be actuated during operation of the shaft preheater.
8. Shaft preheater as claimed in claim 1, characterised in that means for introducing a hot gas stream into the shafts are provided as well as means (8) for drawing off the hot gas stream led through the material layer into the individual shafts.
9. Shaft preheater as claimed in claim 1, characterised in that means for introducing a hot gas stream into the shafts are provided as well as means (8) for drawing off the hot gas stream led through the material layer into the individual shafts, wherein furthermore a measuring device for determining the pressure loss of the hot gas stream is provided within the shaft and the means (9) for limiting the layer height are controllable as a function of the pressure loss.